Help with heat loss and finishing existing design details_1

Mike Krall

hot_rod said:

In all the years I have been installing systems, I have never seen one stuck on DHW, if everything was sized properly

OK... not valid. Thank you.
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Under the theory of DHW recharging that goes, "Get it done and go back to the heat-loss", what temperature of water should the boiler be producing on DHW priority call?

I don't know if altitude has an effect on that... the house is at 6100 ft.

Mike

GGross

Many will set the boiler temp on DHW call as high as they can. You need to keep in mind that if you do that, and your DHW tank is piped as a zone that there is likely a whole lot of really hot water now that will need to be mixed down for any low temp zones. The brand boiler I use normally has separate taps underneath to connect am indirect, so once the call for DHW is done it kicks the little diverter valve back over to heating, the little bit of water that is too hot for low temp blends down quickly with the rest of the system and keeps us in line.

To your question that temperature you are calling for will depend on a few factors, the specific characteristics of the heat exchanger in your indirect, the desired DHW temperature of course. I would imagine the general "I don't want to worry about it" approach would be to set the boiler temp on DHW call to 180, Though I have a whole lot of systems out there that the boiler control will adjust that temp based on usage and it tends to be much cooler than that with great success.

hot_rod

GGross said:

Many will set the boiler temp on DHW call as high as they can. You need to keep in mind that if you do that, and your DHW tank is piped as a zone that there is likely a whole lot of really hot water now that will need to be mixed down for any low temp zones. The brand boiler I use normally has separate taps underneath to connect am indirect, so once the call for DHW is done it kicks the little diverter valve back over to heating, the little bit of water that is too hot for low temp blends down quickly with the rest of the system and keeps us in line.

To your question that temperature you are calling for will depend on a few factors, the specific characteristics of the heat exchanger in your indirect, the desired DHW temperature of course. I would imagine the general "I don't want to worry about it" approach would be to set the boiler temp on DHW call to 180, Though I have a whole lot of systems out there that the boiler control will adjust that temp based on usage and it tends to be much cooler than that with great success.

Good points! On one hand it would be nice to keep the mod con in condensing mode during DHW generation. And it can be dome with large surface area indirects.
On the other hand, git er done would have you run the boiler 190F or so to get back to heat mode as quickly as possible.

I do know from experience that higher boiler SWT does increase mineral precipation on the HX coils or surfaces. So many trade-offs to consider.do

Mike Krall

Hot_water_fan said:

It’s customizable so try different durations. 

Thank you for that...

GGross said:

To your question that temperature you are calling for will depend on a few factors, the specific characteristics of the heat exchanger in your indirect, the desired DHW temperature of course. I would imagine the general "I don't want to worry about it" approach would be to set the boiler temp on DHW call to 180, Though I have a whole lot of systems out there that the boiler control will adjust that temp based on usage and it tends to be much cooler than that with great success.

That is a good understanding for me to have, but I believe this system should not have DHW as a zone. I assume a Lochinvar Knight would have a DHW purge... but ???
I had thought about running DHW priority (or a zone) looking for condensing temps to do it with. I feel I understand there would be ways... but I constantly come up against what I believe is the difficult part of this system... feeding the emitters to steady state while controlling the small solar aspect and other internal/external variants. I'd give quite a bit of 'hot_rod's "trade offs" to get near that.

hot_rod said:

I do know from experience that higher boiler SWT does increase mineral precipitation on the HX coils or surfaces. So many trade-offs to consider.do

I owe you a Lochinvar Knight I&O Manual reading... under the theory of: If you ask for advice, don't argue it.

Mike

hot_rod

I owe you a Lochinvar Knight I&O Manual reading... under the theory of: If you ask for advice, don't argue it.

Mike

For the most part, the boiler manuals do a good job explaining the control settings and functions. As long as you understand the terminology. Don't go past a word or term that you don't understand was advise given to me a long time ago, or the whole concept can be lost on you. Hysteresis throws a lot of people for a loop, for example:)

But I don't agree with some of the piping and component locations shown in boiler installation manuals.

Their products could perform much better, last longer with some updates to their piping diagrams, or suggestions. Over the years some boiler manufacturers have hired an experienced hydronic designer to provide "best practices" piping schematics. I suspect a drop in their warranty claims easily paid for that addition.
The knowledge is out there.

Mike Krall

hot_rod said:

Don't go past a word or term that you don't understand was advise given to me a long time ago, or the whole concept can be lost on you.

Thanks for the key Hot Rod... I'll see how I do with it.

Mike

GGross

@hot_rod

I noticed some changes in certain manufacturers diagrams as well. One in particular stopped showing "direct pipe" options on their firetube boilers and instead show the caleffi low loss header in nearly all piping diagrams. I guess they figure if the application suits direct pipe, the installer can make that plan themselves, which seems pretty smart to me. It made me chuckle a bit as the rep that sold them also had a line of "knockoff" hydro separators they had been trying to get me to switch to for a while.

hot_rod

Installers unable or unwilling to use pressure drop data to see when direct piping will be acceptable. maybe.

The pump on return, or pumping at the tank, and the faux return protection piping are my pet peeve.


Caleffi innovates, many others imitate. A form of flattery I guess?
We have had people break a glass case and try to steal our products at a trade show. Reverse engineer it, build it as cheaply as possible, fake listings, you name it. We have captured product with our logo on it that were copied and turned loose. We are not alone

Mike Krall

hot_rod said:

If the boiler is going to be an 85,000, really no need for any 1-1/4” piping. Have you priced copper lately? Even if the LLH is 1-1/4, reduce all the piping to 1”. You are only going to get about 76 K from the boiler, the heat load only needs about 4 gpm, so manifolds could also be 1” trunk size m, 1” to the indirect also.

I need to make sure I understand this. I'm still stuck with the only view I have of this system from boiler to even heat... my interpretation of the designers view.

Whether the boiler is a 55k or 85k -- the boiler to LLH... to DHW (priority)... LLH to 2-zones do not need to be 1 1/4" for any reasons having to do with ease of heat distribution (ease of "the train" getting where it needs to go... some have said). That 2" LLH to 1" both sides of the LLH is fine?

The designer talked with me in non-technical terms... because it was found I did not understand them, yet I needed to understand different aspects. From that I got "ride to the battle instead of marching to the battle" (boiler heat to emitter loop (or DHW HX), then back).

The designer said "There are many ways...", and Hot-Rod did too. So, I look at these views... the last sentence above and the following quote.

hot_rod said:

Oversizing pipe brings along other concerns, low flow velocity for one. You have about a 3.7 gpm flow required at design, you could probably cover that with 3/4 tube runs

Is there a difference though time... Loch. 2012 boiler vs. Loch. 2022 boiler (maybe DHW tank HX, too) that would make large piping more-OK then, but less-OK now?

Mike

Here is the designed system again...

hot_rod

The pipe should always size to the load(gpm) it needs to carry. Nothing really changed in that respect. If they are using a different design boiler heat exchanger, their flow rates may have changed a bit. Most  boiler manuals will show the gpm they want. Lochinvar use to show a few different delta t conditions.

If you have a long piping circuit, around a building perhaps, you might need to upsize due to pressure drop, resistance to flow caused by additional friction.

In your case I think you are talking several feet from boiler to Sep location?

Mike Krall

hot_rod said:

The pipe should always size to the load(gpm) it needs to carry. Nothing really changed in that respect. If they are using a different design boiler heat exchanger, their flow rates may have changed a bit. Most  boiler manuals will show the gpm they want. Lochinvar use to show a few different delta t conditions.

If you have a long piping circuit, around a building perhaps, you might need to upsize due to pressure drop, resistance to flow caused by additional friction.

In your case I think you are talking several feet from boiler to Sep location?

Where ever the boiler is (it could vary), the LLH would not be more than 3 - 4 ft. DHW right side could be max. 6+ feet from boiler left side (that is the way it is on paper but doesn't have to be).

The only long piping is LLH - ZV's - circ. pump's (some few feet each) - manifolds (30 - 36 feet +/- dn.-under-up).

Maybe the screenshots are what you are referencing. They are from 06/2022. The oldest I&O I found (02/2018) had the same numbers in the chart with different curve graph (different pump and graphic presentation).

I can tell you, looking at the screenshot pages, I'm clueless.

Mike

hot_rod

Mike Krall said:

hot_rod said:

The pipe should always size to the load(gpm) it needs to carry. Nothing really changed in that respect. If they are using a different design boiler heat exchanger, their flow rates may have changed a bit. Most  boiler manuals will show the gpm they want. Lochinvar use to show a few different delta t conditions.

If you have a long piping circuit, around a building perhaps, you might need to upsize due to pressure drop, resistance to flow caused by additional friction.

In your case I think you are talking several feet from boiler to Sep location?

Where ever the boiler is (it could vary), the LLH would not be more than 3 - 4 ft. DHW right side could be max. 6+ feet from boiler left side (that is the way it is on paper but doesn't have to be).

The only long piping is LLH - ZV's - circ. pump's (some few feet each) - manifolds (30 - 36 feet +/- dn.-under-up).

Maybe the screenshots are what you are referencing. They are from 06/2022. The oldest I&O I found (02/2018) had the same numbers in the chart with different curve graph (different pump and graphic presentation).

I can tell you, looking at the screenshot pages, I'm clueless.

Mike

Well they show 1" all the way up to a 155. In theory if you had a 55 running 35 delta, minimum flow shows 3 gpm, actually as low a 2 gpm high fire they indicate. So 3/4 pipe could handle that.
But by their chart and using pipe sizing tables 1" should work for your application just fine. I'm pretty sure the boiler connections are 1" also.

The pipe runs from the LLH to the zone manifolds also size by flow needed and pressure drop calculated for the piping and fittings. Obviously no need for those to be over 1" if the boiler only needs 1" for the entire load. As I recall seeing the design, 3/4 to the manifolds looked to be adequate.

Mike Krall

OK... I'm stuck...

The designer is right and 'Hot_Rod' is right... and so is everyone else in this business who can 'think' these systems.
That group does not include me.

I did a search: "Caleffi Idronics pipe sizing". First 'hit' was this:
https://caleffi.com/sites/default/files/coll_attach_file/idronics_16_na_0.pdf
"...There is no universal method for selecting pipe sizes in hydronic systems. Some designers make selections based solely on flow velocity, while others make..."

Quote under URL is part of first paragraph in "Selecting a Pipe Size"... page 13... bottom right.

I'm going to page 1, etc., to see if I can get some kind of rough understanding...

Mike

hot_rod

Once you are comfortable with required flows, use charts like these. Engineeringtoolbox.com. They drill down to the exact type of tube and are more accurate then some of the rule of thumbs.

The one gives you pressure drop as well as velocity. So if you want to figure each fitting and valve, come up with an EL as described in Idronics 16, you know exactly where you stand, and have the pump size data to boot.

Mike Krall

Bob, I'm never going to get any hydronic system designed out... I can't. Finding that out years ago is what set me to looking for a designer.

I went to Idronics #16 to see if I could pick up enough general awareness to follow along better. I made it OK through page 16... the "lostness" set in after that... though I did find bits and pieces maybe I understand conceptually.
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Two posts up: I mentioned part of the search hit... bottom of page 13... Idronics #16. The whole quote is this:

Selecting A Pipe Size:
There is no universal method for selecting pipe sizes
in hydronic systems. Some designers make selections
based solely on flow velocity, while others make selections
based on pressure drop.

Could those two different approaches cause notable differences in design outcome for piping, etc., with both being sound solutions?

Does the design I brought here look like a characteristic product of one of those two approaches? Which?

The design is attached again below.

Mike

hot_rod

Pressure drop calculations usually kick in for pipe over 2" in size. Also for systems with really long runs over 100'. So the sizing works better using pressure drop in those cases.

In your case you have short piping paths and the spec for both the boiler and the pump they show is 8 gpm. So really no need for 1-1/4" pipe anywhere in the system. Your pump will not move more than 8 gpm, and that is about all you could shove through that boiler without a high head circ and excessive velocity.

So my question to the designer would be why 1-1/4" pipe for an 8 gpm requirement.

Mike Krall

hot_rod said:

In your case you have short piping paths and the spec for both the boiler and the pump they show is 8 gpm. So really no need for 1-1/4" pipe anywhere in the system. Your pump will not move more than 8 gpm, and that is about all you could shove through that boiler without a high head circ and excessive velocity.

Yup... short piping and could be real short, or so it seems.

hot_rod said:

So my question to the designer would be why 1-1/4" pipe for an 8 gpm requirement.

To that I would add... You mentioned maybe 3/4" for remote zone manifold piping would work (1" is spec'ed)...

It seems like there may be a range in flow-based system design. Somewhere in Idronics #16 I picked up on smaller pipe sizing in systems that would then require more pumping power (less copper... yet still a well functioning piping system). If there is a range in flow design for "it works well" (approaches to one job) there would seem to be another end... where required pumping is less. I don't know what component-realities get in the way of that simplistic idea... you-all do though. I would like to know, but I don't need to.

You may have the total of this system well in your head. I don't know that. Downstream of LLH from zone supply/return start/end point, there is 66' and 68' (to and from remote manifold that includes 2x 1" x 12" remote manifolds per).
** 68' has 954' of 1/2" old Rehau PEX (4 x 238.5' = 9.00 gal.)... If 68' is 1" = 11.06 gal... If 68' is 3/4" = 10.24 gal. (manifold S/R + loops).
** 66' has 851' 1/2" PEX (2x 220', 213', 181' = 7.89 gal.)... If 66' is 1" = 9.89 gal... If 66' is 3/4" = 9.10 gal. (manifold S/R + loops).
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Is there anything about knowing boiler wall (Ut. Rm.) realities that would help somewhere along here? There are a couple of oddities (separated supply/return utilidors... hot/cold potable delivery utilidor position). I would do a dimensioned drawing (or describe it in a words/numbers graphical manner). Just say if and how, please
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Sarah and I are heading to the mountains Friday... back Monday eve. Organizing/packing Thurs.

Mike

hot_rod

If the designer used a radiant design program, all this info would be shown. It would have calculated gpm and pressure drop of the loops, and the calculation for the piping from the manifold to the boiler. As accurately as can be done from a drawing anyways.

The software allow you to change an input, hit enter and get the updated calculation, so switch from 1 to 3/4 tube for example, see what changes. But you need a basic understanding of hydronics to use the software successfully, it will flash error if you do something out of acceptable norms

The final number would be gpm required at ft of head for that entire circuit, pex, manifold, and S&R from the boiler. Then that info determines what circulator you would need.

With Idronics 16 you can hand calculate all that, the software makes it a much faster, easier, more accurate job, most times.

What you have is fine, it will work, it is one designers opinion and preferred method of piping, control and sizing. I think it errored on the high side for some of the sizing.

If the original question is will this design work, simple answer is most likely.

Mike Krall

I saw the above post, Hot_Rod... read it through a few times. Thank you. I'll be back as soon as I can.

Mike

TAG

Question: It seems like the OP has a system using one temp water to the radiation -- why all the pumps and bypass? Why all the extra controls ?

My system is using the smallest Viessmann boiler (60's BTU) with ODR and the matching 42 gallon indirect (300). low loss header with one Alpha pump out to 4 manifolds and over 30 loops of Pex . I did use 1 1/4 copper pipe to the manifolds as two of them are 50' away. One of the remote manifolds uses a zone valve since the manifold does one large room -- The other manifolds are the more complex Cross with various room thermostats attached. So the whole thing works on three pumps ...

I designed in thermostats for various rooms just in case and ordered the Viessmann 300 control ... All not needed. Some simple flow adjustments on the manifolds is all that was required.

Hot Rod gave me great advise on the layout

Mike Krall

TAG said:

Question: It seems like the OP has a system using one temp water to the radiation -- why all the pumps and bypass? Why all the extra controls ?

My system is using the smallest Viessmann boiler (60's BTU) with ODR and the matching 42 gallon indirect (300). low loss header with one Alpha pump out to 4 manifolds and over 30 loops of Pex . I did use 1 1/4 copper pipe to the manifolds as two of them are 50' away. One of the remote manifolds uses a zone valve since the manifold does one large room -- The other manifolds are the more complex Cross with various room thermostats attached. So the whole thing works on three pumps

Nobody has answered and I had hoped they would, TAG...

I am not the person to relate this well. Fact is, there is a lot about this designed system I do not understand. I will tell you what I think, though.

Constant circulation is ideal in this instance of very-high-mass emitter. The simplicity of the system falls right in with that. The bypass is the circulation loop when there is no heat call.

The two zones distinctly separate non-solar from solar (the solar half also has the predominant amount of 'other' unaccounted-for internal gain). Those two zones then have to be controlled separately due to their different heat-loss characteristics.

High Mass emitters swing. ODR will not control that. (This is where I'm really unclear)... The 'tekmar 521' are air sensors and they will sense floors (slab emitter). The combination of those two datas decide when to --or not to-- continue heating. I think an aspect of this control structure is to keep the emitter from being either of too warm or cool relative to the desired air temp... so that it can respond (+ or -) more quickly. As I said, I'm close to clueless on this.

Question, or... ???

Mike

Mike Krall

hot_rod said:

If the designer used a radiant design program, all this info would be shown. It would have calculated gpm and pressure drop of the loops, and the calculation for the piping from the manifold to the boiler. As accurately as can be done from a drawing anyways.

I don't know that I understand this... Designer does use radiant design program, as well as hand work. I have never understood what aspects of the design were earlier iterations, though.

hot_rod said:

What you have is fine, it will work, it is one designers opinion and preferred method of piping, control and sizing. I think it erred on the high side for some of the sizing.

My impression is 'Bold' is referring to near boiler and DHW 1 1/4", as well as 1 1/4" secondary side of LLH to zone take offs. Is that correct?

hot_rod said:

If the original question is will this design work, simple answer is most likely.

Part of the original question was 'will this design work'. Thank you for saying that. It is not all of the question, though.

Mike

hot_rod

Mike Krall said:

TAG said:

Question: It seems like the OP has a system using one temp water to the radiation -- why all the pumps and bypass? Why all the extra controls ?

My system is using the smallest Viessmann boiler (60's BTU) with ODR and the matching 42 gallon indirect (300). low loss header with one Alpha pump out to 4 manifolds and over 30 loops of Pex . I did use 1 1/4 copper pipe to the manifolds as two of them are 50' away. One of the remote manifolds uses a zone valve since the manifold does one large room -- The other manifolds are the more complex Cross with various room thermostats attached. So the whole thing works on three pumps

Nobody has answered and I had hoped they would, TAG...

I am not the person to relate this well. Fact is, there is a lot about this designed system I do not understand. I will tell you what I think, though.

Constant circulation is ideal in this instance of very-high-mass emitter. The simplicity of the system falls right in with that. The bypass is the circulation loop when there is no heat call.

The two zones distinctly separate non-solar from solar (the solar half also has the predominant amount of 'other' unaccounted-for internal gain). Those two zones then have to be controlled separately due to their different heat-loss characteristics.

High Mass emitters swing. ODR will not control that. (This is where I'm really unclear)... The 'tekmar 512' are air sensors and they will sense floors (slab emitter). The combination of those two datas decide when to --or not to-- continue heating. I think an aspect of this control structure is to keep the emitter from being either of too warm or cool relative to the desired air temp... so that it can respond (+ or -) more quickly. As I said, I'm close to clueless on this.

Question, or... ???

Mike

Thermostats like that 512 have the ability to use a floor sensor along with the air sensor inside the stat.

Two ways to use that floor sensor. Program it to not exceed a certain temperature, used for floor warming. I use this function in homes with AC that always want a warm bathroom floor, for example. Bathroom on it's own zone of course. Set the floor to maybe 82- 84, about skin temperature, so the floor is always neutral, never cold feeling, never too hot to stand on. In winter it could be bumped. So even with AC set to 75F, the tile floor is always comfortable.

Or program so the floor never drops below the temperature you program. The air temperature is still priority, else the room could go to 90 as it tries to reach them floor sensor setpoint. You could set this to 79 or 80 degrees. If the floor drops to that, heat fires up.

I believe it can be used with floor sensor only, ignoring the air temperature.

These are very fine tuning thermostats.
IF or when you get temperatures set, run ODR and you could see the boiler modulate smoothly with heat demand.

ODR attempts to predict that the system needs higher temperature as the outdoor temperature drops. However that is not always the case and ODR could cause over-shooting, especially in high mass systems. It keeps bumping up SWT, but the load on the home may not be increasing as the mass is flywheeling you through a drop in temperature.

Or internal gains are helping warm the space, cooking, appliances, lighting, people all add heat to the space. So a perfect thermostat and control might use ODR to predict, but indoor reset input to know how the space is actually running temperature wise.

I agree with some experts that claim the indoor input is more accurate, since you live inside not outside. The heat emitters (floor) don't know or care what the outdoor temperature is, they just want to meet the indoor thermostat setting. There were some stats that watched several weather data points and would start to ramp up in anticipation of a drop in outdoor temperature predicted. I'm not sure that over-kill worked so well. I don't see it advertised much anymore.

You need to stop fretting, build the system, as shown or modified as suggested here, either will work. Then live in the house for a year and adjust it to your liking. It really doesn't matter how any of us like to keep our homes. Unless we move in with you

You have an infinitely adjustable system with that boiler and controls, the key to getting exact is YOU.

Mike Krall

hot_rod said:

You need to stop fretting, build the system, as shown or modified as suggested here, either will work. Then live in the house for a year and adjust it to your liking. It really doesn't matter how any of us like to keep our homes. Unless we move in with you

Not so much fretting as fussing, Hot Rod. When I don't get something I dig at it... dig until I've got a place to put a thing so I've got as true a picture as I can make.

I've been doing a bunch of backtracking through all the designer's stuff and though this thread, and a thing popped into my head. The base of this is the fact the posted design diagram is a point in time the actual design went past.

I've just reread your comments on the 1 1/4" pipe sizing. A primary concern you expressed was needing to satisfy minimum flow rates.

IF the boiler was a 110k, would you have the same concern/view of the 1 1/4" piping?

Mike

hot_rod

Always start with the boiler you are considering, many, most have a chart like this telling you the flow rates they would like, at various operating conditions. A 20∆ for example would be a place to start. In addition to the flow they want, it shows the pressure drop through the boiler at that flow. As flow increases so does head as you have more resistance to flow.
Note on the bottom they assume a certain amount of piping in their numbers. Ideally you would add all the piping, fitting, valves, everything in that boiler circuit. As explained in Idronics 16. Develop an EL, convert that to head.

They even suggest a pipe size

Then you have exactly what your system would have for pressure drop (head) Confirm that the pump you intend can move the required gpm at the head your circuit presents. Lochinvar even giver you a selection of circulators that should cover then job.

Your loop is short, as drawn I'd expect only a few feet of head, their estimate may even cover it.

If you want to take it a step further you could develop a system curve, by plotting multiple points on a graph, even graph paper. Use as french curve to connect those dots.

Now you could take that system curve you developed, lay it over the pump curve you have selected.

Where the system curve crosses the pump curve develops the OP operating point. That is what the circulator will actually be moving in the circuit you designed and plotted.

Not many designers take it that far on a residential system. Did yours? It is just an additional step to confirm the pump you select is running in a comfortable point on its curve. Mid point ideally, called the "knee" of the curve. It is critical on large commercial type pumps to find that OP to confirm they are not running "off curve"

TAG

You want to do the heat loss so you know what the building needs -- the whole thing. Next you want to look at the various rooms and make sure what you have for radiation will give you enough BTU's. Each system will have a BTU max per foot. Staple up will be the lowest ... plates will be more ... heavy plates a bit better ... and so on.

One of my first projects was a big old brick cape built just after WWII ... Ducted oil hot air ... very uncomfortable house. It lived like a single floor house with the second floor for guests bedrooms/ siting rooms .... the lower was a full walk out to a pool w/ party areas -- bar and second kitchen. It was block and brick with minimal insulation -- some of the rooms could not be fully heated to design temp just using retrofitted plates on the wood floors. I took the basement ceilings down to fully do plates and used panel radiators on the top/lower floors and Runtal units to supplement the wood on the main floor where it was not enough. That's the only project where I had that problem. Generally -- you can get enough out of a wood floor to heat a space. Never a problem with wet bed tile or concrete.

That's what you need to know. How much heat in each room and will what you have give it to you. After that it is just a question of circulating the water around ...

One of the things I did was over engineer my earlier systems. Fearing that if I did not have every possible problem covered I was stuck as I could not go back and fix. One my new system I went with one temp -- even using concrete/ Warmboard/ heavy plates. I went with the heavy plates on the retrofit areas to better match the Warmboard temp and figured I would play with flow on the concrete. Now -- I did cover my basis and installed 3 of the Cross manifolds and buried wires should I need to zone a room. I went with the Cross because -- while they are more money upfront .. if I did need to zone they make it easy and end up costing no more when you add up all the parts for a standard manifold.

As far as pipe for the main components. Look to your boiler for these answers. I used Viessmann and they have a great application manual. Look it up for the 200 boiler and see the various piping setups. Hot Rod has also posted many great links.

Remember -- the boiler piping will be set up to circulate the flow it needs. That's what is greta about using a low loss header. Follow the instructions for the boiler loop to the LLH and what the radiation needs to the manifolds is another size.

In my case we used 1" for the boiler loop --- the indirect got 1" and out from the low loss header was 1 1/4. Again -- I did all 4 manifold out from the LLH with one Alpha pump. After we had the system up and running I had all the loops open. We played with the outdoor reset curve for a few weeks and then I cut the flow to the concrete floor a bit .. I was able to the whole house working just on ODR. Now -- since that time I have added some thermostats to lower the temp of some rooms. Including one of the area with concrete floors.

OH --- one thing I did do as far a wires --- I not only buried wires for thermostats back to the manifold controlling the pex to the room. I also bought some extra floor temp sensors ($5 from supply house) -- this allowed me to have them in place incase I need them. The sensors are common and while they come with the honeywell thermostat (room temp and floor) I was not going to buy all of them up front at $100.

Mike Krall

Nice day fishing... start early... end late! I really don't do that enough!

So, Hot Rod, your response to my response... was that a Yes, or a No...?

hot_rod

Is the question about what size tube I'd use with a 110 boiler?

I don't see dimensions on your attached piping schematic? I assume 20' or less of piping from the boiler to low loss header?

If so, what boiler have you decided on? An 80, 110 and 105 have all been mentioned or indicated on your plan. The 110 Lochinvar fire tube show 1" acceptable. I attached that on an earlier post. Look up the spec on the exact boilers you are considering. It has 1" piping connections.

The Smart tank noted on your piping drawing also shows 1" acceptable on the 40 gallon. The 50 gallon and larger Smart tanks show 1-1/4, but with 140,000 btu/hr input, shown on their lower chart, which you don't have. So really no reason for 1-1/4 to the tank either IMO.

If you had long runs to the tank or LLH, then the right thing to do would be calculate the exact pressure drop of the circuit.
So without all the required info to calculate the circuit, I'm of the opinion of my earlier post that with either an 80 or 110 boiler, 1" piping under my assumptions is adequate. Comfortably adequate.
Attached is an example of the software I use to calculate circuits, pump, and pipe sizes. A free demo at www.hydronicpros.com if you are so inclined.

Looking at the designers notes, the boiler and indirect have 1" connections. Seems silly that you would increase at the boiler and tanks 1" connections just to oversize the piping??

Same applies on the secondary, with the loads and assumed distances to the manifolds, 1" is adequate, probably 3/4 on the closer manifold.

Mike Krall

TAG said:

You want to do the heat loss so you know what the building needs -- the whole thing. Next you want to look at the various rooms and make sure what you have for radiation will give you enough BTU's. Each system will have a BTU max per foot. Staple up will be the lowest ... plates will be more ... heavy plates a bit better ... and so on.

That's what you need to know. How much heat in each room and will what you have give it to you. After that it is just a question of circulating the water around.

I got the heat-loss done... WIRSBO did it. It seems all the data you mention is there... total load... room by room load. All pieced out into floor, ceiling, "other" (walls, windows, doors). Along with single and total loop GPM and head feet... loop water temps and emitter surface temps... I handed it all off to the designer.

One of the things I did was over engineer my earlier systems. Fearing that if I did not have every possible problem covered I was stuck as I could not go back and fix.

I've been in that place so many times with this house... worry, worry... figure, figure... then find down the road a self created quagmire. Just about anything can be worked around. Well, as long as the true basics are in place to start! A person builds a house of stone, tear outs are really tough.

As far as pipe for the main components. Look to your boiler for these answers. Hot Rod has also posted many great links.

Remember -- the boiler piping will be set up to circulate the flow it needs. That's what is great about using a low loss header. Follow the instructions for the boiler loop to the LLH and what the radiation needs to the manifolds is another size.

Thanks for that TAG. For me it's really helpful to hear the same thing said differently... helps me make pictures of things.

As to your thinking ahead and running wires for thermostats and floor sensors... I saw the thermostat wiring need and figured out in time but didn't have a clue about floor sensors and had to do a work-around I'm hoping holds up.

Biggest "too bad" about this hydronic system is not having found out about FHV proportional control until these past few months. If I had known of them a long time ago, I'd have been right there trying it with MikeT.,SwampeastMO... =]

Mike

Mike Krall

hot_rod said:

Is the question about what size tube I'd use with a 110 boiler?

I don't see dimensions on your attached piping schematic? I assume 20' or less of piping from the boiler to low loss header?

I knew you would use 1" with a 110k boiler. I was wondering if 1 1/4" with a 110k boiler was less "I think the designer erred" than your saying that about an 85k or 55k.

And I knew I should have done a boiler wall drawing even though no one took me up on the earlier mention. I'll get it here tomorrow.
-----------------------------------------------------
I understand you and 'TAG' being right on "what boiler" now. I understand a 55k will work fine for the heat-load. The designer settled at the 85k and that was about making hot water quickly and returning to the heat load... that the size of the boiler as well as scheduling time periods to make it in were important. We had a lot of discussion on that. There may also have been an aspect with the designer on whether we would actually use as little hot water as we do. I don't know that, though.

The 55k / 85k cost difference is very small, and the turn down minimum is essentially the same (8.3k / 8.5k).

Two questions:
** Do you see negatives using an 85k?
** Do you see a functional difference between 55k / 85k in the idea of 'making quickly' and doing so 'scheduled'?

Mike

Mike Krall

Utility room... boiler wall dimensions...

Before you even look (before I even put the .png in)... there is some odd stuff. The story starts with boiler availability for low water temps (without mixing down and all that) 30 years ago. I'll tell it if you either of; need me to, or want me to.

Mike

hot_rod

Mike Krall said:

hot_rod said:

Is the question about what size tube I'd use with a 110 boiler?

I don't see dimensions on your attached piping schematic? I assume 20' or less of piping from the boiler to low loss header?

I knew you would use 1" with a 110k boiler. I was wondering if 1 1/4" with a 110k boiler was less "I think the designer erred" than your saying that about an 85k or 55k.

And I knew I should have done a boiler wall drawing even though no one took me up on the earlier mention. I'll get it here tomorrow.
-----------------------------------------------------
I understand you and 'TAG' being right on "what boiler" now. I understand a 55k will work fine for the heat-load. The designer settled at the 85k and that was about making hot water quickly and returning to the heat load... that the size of the boiler as well as scheduling time periods to make it in were important. We had a lot of discussion on that. There may also have been an aspect with the designer on whether we would actually use as little hot water as we do. I don't know that, though.

The 55k / 85k cost difference is very small, and the turn down minimum is essentially the same (8.3k / 8.5k).

Two questions:
** Do you see negatives using an 85k?
** Do you see a functional difference between 55k / 85k in the idea of 'making quickly' and doing so 'scheduled'?

Mike

No downside I can see going with the 85. All you gain is the ability to recover DHW a bit faster, if that is important, then go with an 85.

Mike Krall

hot_rod said:

No downside I can see going with the 85. All you gain is the ability to recover DHW a bit faster, if that is important, then go with an 85.

Thank you...
------------------------------------------------------
OK... 85k... 1" near boiler and DHW indirect... 1" PEX to manifolds.
---------------------------------------------------------
There are other bits and pieces I don't know how to spec. or what to spec. as well as control views. I don't know exactly where to start with 'one thing at a time' ???

Oh... I e-mailed Grundfos looking to get ECM pump part numbers equivalent to the three UPS15-58FC (2x constant circ... 1x DHW). Got an answer from a distributor to use ALPHA2 15-55F/LC, which are VS type pumps. I was quite specific about what the pumps would be doing as well as the GPM/head numbers and at what speed the three UPS15-58 would be run. Gave boiler brand/sizes also.

You did say VS was not needed here. Do you know if Grundfos has an ECM equivalent of the UPS15-58FC?

Mike

hot_rod

The Alpha 2 has 3 fixed speeds like the 15-58 and a few auto adapt and variable speed functions in one pump. In your case just select the fixed speed the closest to your design spec

https://www.pumpproducts.com/blog/grundfos-alpha2-series-circulator-pumps-buyers-guide/

TAG

Not to be too repetitive -- But. You should down load some piping layouts. I used the smallest Viesmmann 200 boiler to do my church rehab. +4000sf in PA. The boiler manuals are available on line and the application manual shows various piping and control situations for different types of radiation -- it has very nice and easy to follow diagrams. Not specific to Viessmann.

Think I posted in this thread? My boiler in the tiny mechanical room -- I will again. In my case I used two Alpha II's -- the boiler loop just needs a steady pump so the "Auto" part of that pump is a waste -- No one had the version w/o the "Auto" at the time -- it is only about $30 less expensive. The pump out to the manifolds is the same Alpha II -- both are the smallest ones. The loop to the indirect tank is a typical 3 speed -- that's not running very much so no need for anything fancy. The basic pump is about 85W --- the two Alpha pumps when running are only using 14w in the boiler loop and a max of 30w in my case.

Smart pumps are really a game changer -- on one temp systems they make all the old way of zoning with pumps obsolete. If they hold up the 3 Cross manifolds do the same with loop control -- together they make a very simple straightforward setup. I did use one zone valve for an 11 loop manifold -- tied to a thermostat. The Alpha pump just adjusts depending on what is open on the 4 manifolds and 30 odd loops of
.

Mike Krall

hot_rod said:

The Alpha 2 has 3 fixed speeds like the 15-58 and a few auto adapt and variable speed functions in one pump. In your case just select the fixed speed the closest to your design spec

https://www.pumpproducts.com/blog/grundfos-alpha2-series-circulator-pumps-buyers-guide/

And an Alpha2 15-55F for the DHW, or does TAG's suggestion that pump (UPS15-58) is not a big time amount or electricity use make sense to you, also?

Mike

hot_rod

I use all ECM anymore, 50- 70% less energy, to run, better starting torque, digital readouts
Its modern circulator efficiency for modern efficient Hydronics.
  Check for rebates on any high efficiency components

wwwdsireusa.org, click on your state 

Mike Krall

TAG said:

Not to be too repetitive -- But. You should download some piping layouts. I used the smallest Viessmann 200 boiler to do my church rehab. +4000 sf in PA. The boiler manuals are available on line and the application manual shows various piping and control situations for different types of radiation -- it has very nice and easy to follow diagrams. Not specific to Viessmann.

Smart pumps are really a game changer -- on one temp systems they make all the old way of zoning with pumps obsolete.

'TAG'...

Spent some time this evening in your mentioned Viessmann 200 I&O manual. There were a couple of piping layouts there similar to the designed system I have (see attachment). Thanks for pointing this out.

I'd like to use all ECM pumps. Don't have a need for VS, though... just a simple two zone, one temp. constant circ. system with priority DHW. Would like to get those three pumps and a spare... all the same.

There's an attached copy of the rough plan below.

Mike

Mike Krall

hot_rod said:

I use all ECM anymore, 50- 70% less energy, to run, better starting torque, digital readouts
Its modern circulator efficiency for modern efficient Hydronics.
  Check for rebates on any high efficiency components

wwwdsireusa.org, click on your state 

I went to the site you mentioned. Links to other sites. I'll have to dig into it but up front it looked like businesses offering services.

I mentioned to 'TAG'... I do want to use all ECM pumps. It would be ideal to have the three be the same... with a spare because we are out past the end of the supply chain... 3 days would be about as good as a person could expect... 2, if it were my official "special day"... =]

I knocked around Grundfos off and on today. You know I'm not going to "get" stuff and so do I. Would you (or anyone who is interested) look at the links below and then let me know if the pumps work for this system, please? I'm trying to keep in mind you said "did the designer do a hard crunch on the GPM/head numbers". I don't know, but it wouldn't surprise me that it was done. A thing I do know (maybe), the WIRSBO original layout (north 1/2 with 2 equal-ish and 2 not equal loops) had a 286 ft. loop that is now about 240 ft. I have it in my head reducing a loop like that would reduce head (???).

Anyhow... the point... the links take a person to Grundfos curve pages. I looked up 'duty point'. I put the design GPM/head numbers into the two Alpha curves. The points are above the high speed curve a bit. Is that the definition of needing a different pump?

I did note the second to last paragraph in the first link... noting and understanding are different things.
https://grundfos.com/solutions/learn/research-and-insights/duty-point
The 'duty point' entry on the design's original spec. UPS 15-58FC are just under the speed-3 curve... 4.3 GPM - 15.0 head... 3.25 GPM - 16.0 head.
https://product-selection.grundfos.com/us/products/up-ups-series-100-north-america/ups-15-north-america/ups-15-58-fc-59896341?tab=variant-curves&pumpsystemid=1644777631
This is the pump we talked about already Alpha2 15-55F/LC. Duty points above curve.
https://product-selection.grundfos.com/us/products/alpha-north-america/alpha2-north-america/alpha2-15-55flc-99163906?tab=variant-curves&pumpsystemid=1644893521
I found this: Alpha1 15-55F/LC... Looks like same pump as above, w/o 'Auto Adapt' and 'continuous pressure' settings... just 3 speeds. I think the highest curves for the two Alpha's are identical... but ???
https://product-selection.grundfos.com/us/products/alpha-north-america/alpha1-north-america/alpha1-15-55flc-99285998?tab=variant-curves&pumpsystemid=1644802512

Mike

TAG

How many part do you currently have for this system ?

Why not get a boiler like the Viessmann w/ ODR and ditch all those controls?

You don't need all those pump controls.

You don't need pumps and zone valves together.

you don't need all those air separators.

you don't need two pressure tanks



look at my system: Single Spirovent to remove air. Combination fill valve and small pressure tank. 3 pumps (primary boiler/ secondary/ dhw) The one alpha does all 4 manifolds and two of them are 40 feet away. The Viessmann manual shows all of this.

When I turn on my boiler -- it turns on the two pumps that are wired directly to it. Since it's modulating and using ODR It's going fire and make hot water based on need and the two pumps move the hot water around based on the curve. You want the Alpha type pumps because they use so much less energy. The boiler loop is static -- so if you can get the Alpha I w/o the "auto" great. You want the Alpha II after the LLH because it will ramp up and down based on what loops are open. The use of the more expensive pump for the hot water indirect is up to you .... my tank may fire once or twice a day for however long .... not going to use much power.

You have all these controls for the zones ? That's why I used the Cross manifolds for three of my manifold needs. The thermostats just connect to them and they open and close each loop based on room need. There does not need to be any direct connection to the alpha pump .... the pump reacts to the opening and closing. Same with the one large room with retrofitted plates and 11 loops of 3/8 pex -- this is controlled with a zone valve. No need for expensive Cross with that since I want all the loops on that manifold to flow at once. The zone valve opens and feed the manifold. The Alpha reacts to the zone opening and increases speed to flow. The zone valve does need 24 volts -- used a simple inexpensive switching relay with an on off switch for summer.

The only reason I used the Cross manifolds was for overall cost and ease of hook up. One area of the building is two rooms (slab radiant) both about the same size with 4 loops each. I could have used 2 4 loop manifolds and two zone valves or an 8 loop manifold with individual loop heads on them -- when you price it all out ........ easier to just get one 8 loop cross that comes with all the parts you need to make it all work. connect two thermostats directly to the included cross controller. linking each of the 4 loops together -- the controller knows to open all 4 on call from single thermostat. On the other two Cross manifolds I had the potential for at least 4 zone heads. The heads for regular manifolds are not cheap and you need power and controllers for them. What you find is after dialing in the ODR curve over some week you can get most of what you want with little control and the zones end up being for lower temps in some not used areas and to avoid overshooting in areas with lost of solar gain