Can someone please explain the the VR1816s constant pressure curve

Gordy

download them off Caleffi site. If you have an iPad save them in iBooks.

Gordy

If you really want to monitor, and tinker with some real lab results. You need to monitor the following accurately.

Flow rates, at boiler, and loops.
Outdoor temps.
Indoor temps.
Loop temps
Boiler supply, and return temps.

Doing all this with seperate components can be daunting.

Doing this with multi point data logging saves your time, and puts everything together in a nice package to view with graphs.

Having that ability to produce a graph that shows all monitoring points together is more compelling.

Logging temps is not a big deal. Flow rates could be a hurdle with a data logger as far as cost.

Now having components in place so you can create/force different scenarios is where a flow setter meter could come in handy.

Personally I would rather see what the component selection does on its own with correct selections. The pump in particular.

keyote

Hotrod reading the lit on that thing seems like it ought to be close to full port wide open its a ball valve, they suggest on return side which with that temp gauge would give me an idea of DT by manifold since ill know the SWT already, Are you saying i could switch back and forth on the dry well to pressure gauge somehow ??
Gordy I believe the boiler does log some but its going to be limited by its sensors, the honeywell redlink tstat stuff has an interface and i think some logging as well too, but i dont think they will read each other, the boiler might read the tstat as a call and log duration? no idea really. how to do what you suggest would be great if reasonable,was drooling over the conxus but again not sure thats more than a mobile face of the smart control though someone said the data is a bit more fine.

keyote

Of course im hazy on whats between the boiler control and the honywell redlink tstat and wireless base. i thought maybe the caleffi zone panel was a bit more complete than the taco cant remember why now. but im not clear if i even need one or if i can just wire it all into the boiler. I mention because i suppose it might turn out if i need several components in between some sort of bis thing might do it all for not much more but hope not sound expensive

keyote

Gordy i should have all dta you suggest if i put hot rods thing on the zone i put clip on temp gauges on loops by manifolds dont know how accurate though the tstat and odr will be readable through the redlink and boiler

Gordy

A multi point data logger gives all that in one package. No running to the boiler, then the tstat, then various points in the system writing numbers down, and then putting them together in a meaningful format.

keyote

I see the VT2218and VS1816 on ebay for hundred bucks each tempting to actually just try both pumps for fun though i wonder about ebay as a pump source prefer supply house. com which is also kinda sorta a local plumb supply to me.

keyote

when i google multi point data logger its almost as much as the boiler. \
But if im standing in front of boiler and the redlink is giving me the tstats and the boiler its data and i have some gauges/meters on the near boiler piping i wont need to run around except for the clip on loop thermometers and flow meters but i don't see how i can help that unless actuators send signal and i use them

hot_rod

I suggested the 132 quicksetter if you like to watch and tinker, not really as a balance device if you have a VS pump.

Wait and see, I'll bet the boiler has some data logging capability onboard, via the Conexus.

You can find some powerful and inexpensive catalogers on e-bay.

IF for some reason you want flow datalogging the Grundfos vortex sensors are very commonly used. Some Grundfos pumps have a place in the volute to insert them. This is what the solar, and computer server room coolant pump modules use for flow monitoring and alarm..

Our solar controllers all include a heat metering function, you enter a flow rate and two sensors watch the delta T and calculate either BTU/hr or for Europe KWh. It does the correction if you use the variable speed function on the pump.
Surprisingly accurate when we compare results to certified rotary type BTU meters. A poor mans Btu metering method.

It really depends, again on what data you want or need. Depending on the sampling rate, the data gets big quickly, Probably overwhelming and unecessary unless you enjoy number crunching.

keyote

Thanks hot rod,
I do kind of like data, probably why I kind of drive you guys crazy, I'm sort of forced by circumstance to build this system before Im really educated enough But Ill continue my studies once its running hopefully without more soldering.
I think those caleffi quick setters i was looking for reasonably priced flow meters couldnt find any thanks.
will be a great info source if the pumps flow meter is not accurate, and putting one on the return risers will really improve the picture.Ill double check if the boiler has a flow meter i dont recall one, it definitely data logs what it has sensors for.I could build a neat arduino logger, its the sensors that get expensive if they are digital output.

BTW any opinion on this?

-" So it seemed the consensus was that the 1.25 header was sufficient at 1.98 fps, this boiler has a 1'' supply return port im wondering whether to stay at 1'' including the pump, dirt airmag discal etc then jump 1.25 just before the zone valve header. saves a little on parts and i think it drop pressure where i want too.
The only thing is the indirect is already all in 1.25 so I'd have to put a reducing tee on boiler, that was 1'' for the CH and 1.25" for the indirect"

hot_rod

The Lochinvar I&O should have a recommendation. If max. flow requirement is 8 gpm or less 1" should be fine. For both boiler and indirect S&R that is.

keyote

Thanks hot rod
yes i was going to just follow there direct piping sketch except put the pump expansion and air elim on supply side. as i told you on the TT i just used bushing inside the drain valve unions i put on boiler ports to go from 1to 1.25 inch, and i could simply put those back on the new boiler and do it all in 1.25, i just thought perhaps the sudden step up from 1 to 1.25 at the ZV header would help a bit but if its really insignificant then ill keep the entire loop 1.25

hot_rod

keyote said:

Dont suppose there a way to get the back issues of idronics i know i can read them online

I can mail you set of the hard copies if you would like PM me you mailing address.

keyote

https://attendee.gotowebinar.com/recording/8604104363874301441

Well if anyones interested hers a TACO webinar on how the two pumps operate starting at about 31:30 with the VT. The short answer is the VT is infinitely variable of both head and flow within that band; the VR is not, the VR is basically you have 4 flat fixed head curves you can choose from, thats going to lead to short cycling, which is what I thought if youre not sitting on your bucket changing the curves youre only occasionally idealized.. So not only is the VR minimum head 5 thats its only head, on that setting, whereas the Vt has a minimum head of 0 up to 18 depending on flow

Gordy

keyote said:

https://attendee.gotowebinar.com/recording/8604104363874301441

Well if anyones interested hers a TACO webinar on how the two pumps operate starting at about 31:30 with the VT. The short answer is the VT is infinitely variable of both head and flow within that band; the VR is not, the VR is basically you have 4 flat fixed head curves you can choose from, thats going to lead to short cycling, which is what I thought if youre not sitting on your bucket changing the curves youre only occasionally idealized.. So not only is the VR minimum head 5 thats its only head, on that setting, whereas the Vt has a minimum head of 0 up to 18 depending on flow

How do you know the vr is going to lead to short cycling?

How do you know that one of the four vr flat curves will not accommodate your system?

keyote

well thats what the taco guy said about 20 times in the video me personally i dont know nothing. but he did quote me as saying the DT pump does everything the DP pump but more.

Well the reason i half understood, and seems to be confirmed that it a flat curve wont work is because its flat, so i could pick one that matched the season or certain amount of valves open at a certain temp but when one of those change and the heads flat it will force the flow to do what it wasnt designed for.so if i pick the 5' head setting it will deliver the proper flow when the proper head is 5" but when the heads supposed to be 8' or 1' it will pick a flow on the 5' head curve. where as the VT will maintain both within that green band.
I think the confusion is these delta p pumps dont adjust the way we think or at least i first thought, yes they speed up and down but heads fixed [flat] so only flow is changing, but different zone have different heads and different design days different designed heads, to answer your question [if i understood the video] on my 60 degree day when design says .5 gpm at 1.7 " its going to say well cant do 1.7 ft head only 5" and lowest flow at 5' is 4.5 gpm close enough, which if im understanding means a lot more passengers getting off trains faster. so call is met faster and short cycle

Gordy

Your forgetting about the ODR.

Gordy

Short cycling is when the boiler bounces off HL multiple times with short on times before set point is reached. Not to be confused with reaching set point quickly.

keyote

probably more like not quite understanding it yet, how i think that works is my design has water temps for design day and the boiler has a sort of ratio that takes design day temp and adjusts it as temp changes. in my case design day is 127 degrees and 65 degree day is 91 degrees. now im told this could be off a bit, or SWT might need to be higher at boiler to be right at the manifold, or the ODR ratio can be changed a bit in the KHN it can be changed to say only effect the warm days and not the colder days,and of course theres ramp delay, and theres boiler loop DT etc. but bottom line as i understand it when i look at my design in loop cad the 65 day says .5 gpm and 1.7 ' head anf 91 degrees and design day says 7.6 gpm 8.2 feet head and 127 degree water.

so what i think is supposed to happen is the boiler is set up to have 127 degree water on 17 degrees design day and use the odr to adjust the SWT down to 91 degrees on 65 degree day. and those are assuming the designed heads and flows. If i allow the thermostat and boiler to just work it out between themselves then why did i design.
gpm=btuh/dt x 500
so the dp pump can ignore head and just flow whatever on that fixed curve or boiler can ignore both and adjust SWT or i can enforce the plan of a given swt at a given odt at a given flow and dt and gpm. Now honestly i think it appeals mostly because i trust the design over my zero experience of anything else, i know how i can get the enforcement accomplished where as the other way seems more about trusting years of experience and that the pump and boiler will come to an understanding without me really knowing what it is.

well i ordered the boiler and the caleffi flow meters with temp gauges for the return risers, ill start with the vt pump and so will have its gpm dt temp info as well, it has an internet address cool, also all the boilers sensors, i ordered the con x us. and the honeywell redlinks tststs and other sensors, i have some leftover gauges so ill put one on the return before boiler we will definitely know what happening. might even mount an old ipad on the wall And im going to leave enough room to easily add a buffer and boiler pump in case.

SWEI

Out here in the real world, many of us have been installing ΔP pumps with mod/con boilers and ODR for years. Literally millions of them are installed this way in Europe and North America and (when properly sized and applied, especially with proportional zone valves) they work quite well together.

I have great respect for Taco, but ΔT control (at least in the form we currently have it) is not the be-all and end-all to variable speed pumping that some would have you believe.

Gordy

You will most certainly not need 91* water on a 65* day nor the heat on....

Tinman

Cycling is not equal to short cycling. Different animals. You're over-thinking the hell out of this.

keyote

I really dont have a dog in this fight i only understand the dt method a little more clearly. i only chose it to try first because the majority, if not all of you suggested i do so, albeit with some caveats.
In the taco seminars i watched they recommended the dp pumps for european style systems with proportional zone valves but mine is a on off zone valve and radiant.
yes gordy you said that about the 65 degree day and i just use it as an example because i have actual numbers for that theoretical day but somewhere there is a 59? degree day and it too will have flows and heads way below that Vs pumps curve, the vs pump isnt even enough on the high end at the highest curve.As far as i can tell all a DP pump is is a fixed speed pump with a built in pdbp What i really dont understand is the objection to the VT pump.no ones gotten me to understand why its bad.
Am i wrong about how the odr will work on the boiler, its not possible that the boiler will just raise its temp wildly to accommodate valves opening and closing causing the fixed heads pump to over pump ?
yes i am an over thinker but id rather be an over than under thinker

hot_rod

Capco is one of the top Hydronic wholesalers in the US. I presented a class there recently and 40 contractors showed up. They have a loyal following.

They sell hundreds of the Lochinvars and Viessmann boilers with single pumped Grundfos Alpha ∆P circulators. They offer nice Visio layouts and wiring schematics for their customers.

They have a design book showing the most typical piping and wiring schematics. The cover shot is at their counter area where several boilers provide heat and snowmelt, the counter has a radiant wall system, real nice.

As long as you have a minimum 1.5 gpm flow, Lee tells me the KHN and Alphas work just fine, TRVs or ZVs.

keyote

Thanks for that Bob BTW ordered the flowmeter with gauges and the discalmag arrived yesterday.I had to get the order going or i wont have heat for tenants so really based only on majority opinion i picked the VT to try first i really think im going to order the VS as well to see the differences. so i didnt mean to restrt the controversy i only found some videos on flo pro that had a lot of graphics that made some things clearer and thought id mention because they seem to my novice ears like they address some things you guys say But you all have probably seen them anyway. I was a bit encouraged to find i understood a few things correctly. One is they say a system like mine will certainly work with either pump but that DP pump does indeed have a fixed curve and so its only adjusting flow along that curve which will lead to over pumping and so rising delta ts which could lead to short cycling or at least shorter cycles and higher water temps which i would think is a bad thing for a radiant and mod con. in fact he seemed to say exactly what i have been saying that on days when i need lower heads it can only give me higher flows instead. which is odd because i think thats an objection ive heard to the DT pump but with the DT pump you can enforce a DT which i would think means you can enforce slower water if you want.another point they make is using DP pumps as zone pumps what will happen on a system without trvs is the pump will never change speed because there nothing to make it change speed whereas a DT pump can adjust to differing loads etc
IM really really really really not being argumentative just talking out loud about what i learned.
But again im not clear on the other side. an example of how the DT can screw things up, or how the DP wont just wok but work better.Theres just something about the DP im not getting while the DT seems so straight forward maybe its just we all get temp but pressure is a bit more obscure though i have training in tinside and am a pilot so pressure is not alien to me. well we will see soon lots of gauges and apps coming

SWEI

Hatterasguy said:

The DT pump has a very fast response to any change in SWT. It can go from minimum speed to maximum speed in just about 30 seconds.

Which works just great as long as something else with a brain isn't controlling the fluid temperature. Think conventional cast iron boiler, a single zone of emitters (radiant floor fed from a mixing valve) or an air coil. They do have their uses.

keyote

Thanks Hat for reminding me its a lot to keep in the air.
So im guessing youre talking about zones opening with cooled water the boiler needs to mod up a bit, and the pump doesnt know what temp is but it lost its groove and it will speed up to catch up so boiler has to catch up with temp even as flow increases.
Ok but first i dont see why the boiler will have a hard time catching up when its going to never be working over 60% and usually way below. Maybe you mean more that it will have a hard time not over shooting. But the pump as you say is only going to speed up for a short while, its not trying to chase the temp only the DT so maybe water temp dropped from 127 to 97 when two cold zones opened but the pump wants to speed up to get the return water hotter. with a total of 40 gallons in the system it can move all the water through the system in a couple three minutes and the boiler can raise it in one pass. but trying to be so aggressive might overshoot? maybe whats needed is a slower boiler say by setting the ramp delay or one of their other controls like boost or anti cycling. Im not familiar with how aggressive the boiler will be at default settings, I would think the dt will not be pumping any faster than any other pump would on a cold strt but this boiler can definitely be paced i ordeed flow meters for the return risers we will have lots of info i may get a lazy boy installed down there place everything has an app so i can even watch it on the john

keyote

Hat yes this is pretty much what I imagine might happen,and what we are worried about, and i imagine you have watched happen.I may indeed require a buffer. I am piping in a way i can add a buffer and P/S fairly easily.since I am beginning operation in fall with only one zone and the cellar fintube ganged for ballast, it will be a worst case experiment. I think this conxus board will allow me to see the modulation % while im looking at the header and individual risers S/R water temps and flows from gauges.Hopefully substituting buckets for milk crates wont effect data. I think its doable with this boilers control ability, of course I have never programmed a boiler or done controls so its all a bit vague but they have a six stage ramp delay that you can change both the time and degree increase infinitely on each stage. as well as several other features which seem promising for the scenario you describe.after last nights ruckus i ordered the VR pump as well, we really need to settle this for science sake.

I have been worried since a few guys voiced deep concern that my not using the preformed aluminum plates will really hinder heat transfer.my concern increased when i realized the tenants have a lot more furniture than i imagined they would. Although the only other radiant I have experience on was a renovation i did where they wanted radiant for a master bed bath dressing suite and i retrofitted a mixed down zone from their baseboard system which i installed from the top suspended between joists with fiberglass batts below then sub floor and 3/4 hardwood above. it worked lie a charm i was relieved to find my "engineer" being some internet radiant supply house it would warm up in minutes so I am hopeful still. However its really hard to route loops in a way you can nail down hardwood particularly the leaders, and furnishings is an uncontrollable variable so im seriously thinking doing the rest of the house in radiant ceilings which apparently actually work well.

keyote

So high limit is when a boiler exceeds its swt setpoint? and will shut off? the KHn seems to have a way you can change the degree and time allowed above setpoint that should help?

keyote

Hot rod i managed to get the resolution up enough to look at the schematic you posted i see the flow switch is jumped and was reading boons flow switch post. so im curious about that. looking at boons issue i read the minimum flow detection rates of the switches is 4.5 gpm and wondered what good it would do on a system like mine that may seldom see that much flow.Though i think i may install one on the pex sprinkler system i installed.BTW caleffi should think about the fact that uponor was the only manufacturer of pex sprinkler components and most are really simple like a pex by FIP bull head that can be mounted. you have to use their expansion pex and very expensive tool as well.

Gordy

The most compelling data is that in which the recording of all Data points together at precise points in time. Then tranfered to a line graph showing each of the graphed data points on the same graph. It can be an eye opener as to how the system works in unison, or how it's not....

The more data points the more detailed the picture.

hot_rod

You mentioned:

but with the DT pump you can enforce a DT which Ii would think means you can enforce slower water

I'm not convinced "enforcing" a ∆T is required or even possible. I think the ∆T has a low end lock, via a min speed restriction, so at some point potential enforcement ends.

Heating systems and the structures they live in are dynamic. I feel the ∆T should be dynamic to a point also. If it varies a few degrees from design it probably would not be noticed, harmful, and could even have advantages, like coming out of a setback for example, or power outage.

The boiler and distribution don't always work with the same understanding regarding flow rates and transfer of energy. Heat transfer is not a linear function. Heat transfer doesn't need to and may not be able to remain a fixed ∆ as flow changes. Furthermore the boiler ∆ and the distribution ∆ may never want, need, or be able to line up.

Adding one more microprocessor trying to enforce a different set of conditions from what the boiler control is trying to optimize, and at a completely different rate of response, doesn't seem to be a viable, as several here have discovered.

Give it a try, but know what you are looking to accomplish, so you know if you arrive at that goal.

The Idronics 16 I sent you makes this heat transfer mechanism pretty understandable, and first hand results from several of the designers and top installers confirm that the numbers and concepts in the examples match reality.

Gordy

Personally I would have started out with K.I.S.S. Leaving options for add ons in the system, and see how that works, and build from there as needed. But I like to see how far simple can go before intervention is needed.

This system has evolved from a basic mod/con system to the full monte with out even knowing whether or not it is warranted.

keyote

I know gordy but how to accomplish that? I will be able to see the pumps app and panel, the gauges and meters on the near boiler pipes, the honeywell redlink app, and the conxus data simultaneously but convincing you guys my bucket perspective was true will be tough without it all in one log. i dont see how to fix it without spending thousands. The conxus logs great but it wont have the pump infor or the flowsetter info as far as i can tell gauges that record flow digitally are very expensive as are the data mangers that record it. I think the boiler will at least give the system flow s/r temps pressure and its modulating info

Gordy

Well said Bob. It is the whole system including the envelope that makes everything sporting. The envelope in itself gives considerable lag, and even lead time to the whole system dynamics.

I can see trying to maintain a maximum delta we like to see in a certain type of emitter. From there as the delta narrows who cares it really has little effect on comfort. Is it wasted pump energy? Maybe, but how much really.

keyote

its funny Im of two minds i like simplicity and frugality which is why I was so stubborn about non P/S, at the same time I like information because i like to over think. When buying an expensive item i go to war with myself in this exhausting way one side arguing my frugal simplistic side the other arguing the long term frugality, so in this instance the used TT110 the frugal simple side won, but when it became apparent my boiler info was out of date by several years and i would need a buffer and second pump I switched the argument to the lochinvar can be had for the cost of the buffer pump and what i can resell the TT for. But then it gets insidious because now i start thinking, its silly to have that fancy boiler without the fancy control panel for a little more when the rest of the system comes with apps built in.
BTW i sold the TT110 last week on craigslist for $1500 and made a $500 profit

Gordy

keyote said:

I know gordy but how to accomplish that? I will be able to see the pumps app and panel, the gauges and meters on the near boiler pipes, the honeywell redlink app, and the conxus data simultaneously but convincing you guys my bucket perspective was true will be tough without it all in one log. i dont see how to fix it without spending thousands. The conxus logs great but it wont have the pump infor or the flowsetter info as far as i can tell gauges that record flow digitally are very expensive as are the data mangers that record it. I think the boiler will at least give the system flow s/r temps pressure and its modulating info

I/we have no idea as to the proximity of the data reading points are in reference to each other to get accurate readings at similar points in system run time. I'm just enforcing how important that is if you are going to be producing usable data from your system.

Writing down the data, and recording into a format is not hard. Graphs paint a good picture of how each data point relates to one another.

I see your all in on this so just want the results to be meaningful so we all can analyze it.

keyote

And I am going simple before intervention, the flowsetters conxus etc are toys im rewarding myself with although they will make my novice balance and commision easier.

but im piping non P/S non buffer, but have though about how I could squeeze them in if i fall flat on my face its really just a matter of not crowding the boiler with the DHW and system pumps so I can just connect the supply and return near the boiler with another pump and tee off it to the buffer. but Im optimistic

Gordy

Hatterasguy said:

hot rod said:

I'm not convinced "enforcing" a ∆T is required or even possible. I think the ∆T has a low end lock, via a min speed restriction, so at some point potential enforcement ends.

You really should be convinced based upon the simple premise that lower RWT improves the efficiency of the mod-con dramatically, especially in the sweet spot between 120F and 135F.

Sure, there are "issues" to be managed with the DT pump and the boilers cannot accept flow rates below 1 GPM. However, don't ever consider this pump to be inappropriate for the intended goal.

I've struggled with it myself but am still pursuing a final solution for it. If and when I achieve it, the performance benefit as compared to the fixed speed (based on specific zones calling) DP pump is simply incomparable.

I have to reiterate this all comes down to the system dynamics.

Mass
Emitter saturation.
Heat loss. How rapidly the structure losses heat.

keyote

Hot rod you are correct or at least Taco admits as much in two of the several delta pump videos i watched they admit that when a call is below the lower parameter you essentially get a mini version of what happens with the delta P pumps. The pump cant give the low head and flow system requires and will jump up to the bottom of the range as if that were the fixed curve of a delta P pump. But their argument is this happens relatively rarely while the DP pump you must pick a head and all that can change is the flow along that curve so whenever your call doesnt match that head you will get less than ideal flow, with the DT any head and flow within the entire huge band is possible. The other thing they mentioned is they at first didnt have a minimum speed[curve] but that cause weird situations like the pump seeing equal supply and return and not coming on and other problem so they programed a low minimum parameter. They are really clear DP pumps were made for european TRV and work better and really well on them the trvs are resp[onding to conditions and the DP pumps responding to the TRVs but in open closed ZV systems the ZV is not adjusting but the DT can. One point they keep stressing is the difference in how european and american systems evolved with euro systems usually having high head low flow and american low head high flow.granted radiant has the high head from long length small tubes but its not trv controlled. my guess if im actually starting to understand this is instead of open closed actuators on loops TRV type maybe controlled wirelessly would make a DELTA P pump a better choice for radiant. -thats if im understanding and taco isnt selling me a bridge