gut rehab, reuse old radiators

mark_3

I have an old home (1840's) I just purchased in MA. It sat for years vacant and vandalized, so I gutted it out to the studs and started from scratch (except a few surviving details). I will have four individually heated and metered 1-BR units at about 900 SF each.

I am not a heating expert. I think I would like to reuse the old cast iron radiators in hydronic systems for each unit. I have seen articles posted about having a manifold or riser with seperate runs to each radiator using PEX which allows for balancing at each radiator and avoids temerature drop issues related to installing them in series. My plumber says the old radators can be used for hydronic heat, but the cheapest solution is baseboard in series. I understand there is less plumbing with baseboard. He says that part of the additional expense is because I will have lots more water in the system and will need a bigger furnace. Why would I need more output if the room heating requirements are the same regarless of heating system? In your opinion, is reusing the old radiators a luxury or a smart investment in aesthetics, comfort and efficiency?

On a related note, the old radiator valves are gone. Is it difficult to refit the old radiators with new valves? if PEX is used, how do you get from PEX to radiator and have it look relatively original? Is there a common solution for this?

Sorry, Lots of questions! Thank you for your help
Mark

Steamhead

Definitely use your radiators

You will not need a bigger boiler- the water will just be cooler than it was originally, due to the reduced heat loss. Size your boiler to the loss, and make sure it can handle low-temp water.

You can transition from PEX to copper or steel under the floor, and use Thermostatic Radiator Valves to control the heat in each room.

I wouldn't think of using baseboard when you have glorious old cast-iron radiators that will warm you thru to your bones!

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Floyd

Sounds like you....

Need to talk to another heating man!!!!
Check the "Find a Contractor" feature to the left.
There are more ways than one to skin a cat!!!!
get some more ideas.
KEEP the rads and figure out the BEST way to make them do what you need them to do.

Floyd

Boilerpro

For best efficiency and comfort...

use the old radiators. Radiators, in general, produce about 40% of their heat output as radiant heat, just like the heat from the sun and from new highly efficient radiant floor systems. Baseboard produces only about 15% of its heat as radiant, they mostly heat the air. The higher the percentage of radiant heat produced, the warmer objects in the apartments will feel and, therefore, the more comfortable they will be at a lower air temperature. The increased mass and water content of the radiators also means they will change temperature more slowly, providing more even heating. As stated previously, the boiler only needs to provide enough btu's to heat the building. In fact due to the higher system efficiency of a radiator system, the boiler probably will be smaller than with a convector system. One last thing, since apartments tend to have a relatively large number of people in a smaller space, there is alot of internal heat created. Due to all this internal heat, the boiler can be smaller than a standard heating load calculation will give (definitely only go with a contractor that measures the walls cielings, windows, etc and figures out the R-value for the calculation). You may want to stage fire two boilers,if the load is large enough.... it will improve heating plant efficiency and decrease wear. Also talk to a contractor about indirect fired water heating, you'll be glad you did. If you're in Northwest Illinois, drop me an E-mail maybe I can help.

Boilerpro

mark_3

thanks you. thoughts on PEX?

thank you all for the great advice. I have the place completely gut out. Is PEX a good way to go or should I run pipe since it is all open? Pros and Cons?

Mark

Roger Litman

Reuse of old radiators

There are two caveats on the use of these old radiators. First make sure that they are leaktight and will hold air/water before you hook them up, and second make sure that the sections are joined at top as well as the bottom so that they can be bled, you may need to drill and tap the radiators to bleed them and that is not the easiest thing to do. While I agree that there is a certain charm in the reuse of these old radiators, if you are doing a gut rehab and remodeling, I would question the joining of different styles in what i believe is a rental unit.

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mark_3

convection versus radiant heat

Hello again and thanks for the help! I spoke with my heating plumber about some of the advice I received here on keeping the radiators. He said that a large part of heating with a radiator still comes from convection. A high temperature was needed to get the radiators hot enough to convect, and thus a larger BTU boiler was needed to get all that stored water hot. In addition to convection problems, he also mentioned something about condensation being an issue when running boilers at low temperature versus the 180 degrees range.

In short, he wants to size the boiler based on the amount of water in the system so that the radiators can be brought up to temp rather than based on a normal heat loss calculation. Is there any truth to this? Off the top of his head he estmates a 70,000 BTU boiler for the radiator system versus a 40,000 BTU boiler for all baseboard.

I have asked him tp price out a baseboard system since it seems like where he wants to go, but would still like to weigh the radiator alternative as I am not a fan of basboard heat.

Any additional guidance is appreciated!
Mark

Floyd

Mark!!!!!!

A BTU is a BTUis a BTU...... they do not come in different shapes and sizes!!!!!!!
If the space can be heated with 40,000 in the baseboard configuration than it will
also be heated with the rads!!!!!!
Actually you WILL get more radiant heat and less convection from the rads, but that
is BETTER!!!! The baseboard is mostly convection and that will not be as comfy!!!!
Don't know how else to say this!!! But your contractor is all wet!!! (pun intended)
Find another guy!!!! your not married to this guy, so ditch him and get someone that
knows his sh.... I mean stuff!!!!

Just my very humble 2 cents!!!

Floyd

mark_3

learning curve

Thanks for weighing in. I am on board with the radiator benefits and the math... or 95% sold anyways! In my limited experience I know conditions in the field sometimes mandate solutions that are not intuitive and I want to be sure that I am not missing anything here before making this major decision. This plumber has been doing heating systems for 25+ years so I am trying to give him the benefit of the doubt, do some homework and figure out where he is coming from. This type of system may not be his cup of tea... but just in case he's on to something here I am!

Floyd

There are many....

that have been doing things the same old way for 25 years......
That does mean that it is right....I have done the ripp out the rads
deal in the past....only to find out that I was wrong.....man that's tough to
admit!!!!
You may be happy with the bigger boiler and the rads.... but you won't know
any different..... you won't know what could have been......

Floyd

Boilerpro

I'm right on board with Floyd..

> Hello again and thanks for the help! I spoke

> with my heating plumber about some of the advice

> I received here on keeping the radiators. He

> said that a large part of heating with a radiator

> still comes from convection. A high temperature

> was needed to get the radiators hot enough to

> convect, and thus a larger BTU boiler was needed

> to get all that stored water hot. In addition to

> convection problems, he also mentioned something

> about condensation being an issue when running

> boilers at low temperature versus the 180 degrees

> range.

>

> In short, he wants to size the boiler

> based on the amount of water in the system so

> that the radiators can be brought up to temp

> rather than based on a normal heat loss

> calculation. Is there any truth to this? Off

> the top of his head he estmates a 70,000 BTU

> boiler for the radiator system versus a 40,000

> BTU boiler for all baseboard.

>

> I have asked him

> tp price out a baseboard system since it seems

> like where he wants to go, but would still like

> to weigh the radiator alternative as I am not a

> fan of basboard heat.

>

> Any additional

> guidance is appreciated! Mark

tombig

Radiators

Why would you mess with an existing piping system in a rehab/rental unit unless you were seriously moving walls? Unless the radiators were extremely obtrusive there would be little reason to alter the delivery system. If you are going to provide heat for the tenants with a single or staged boiler(s) at your expense you need to adapt yourself to the building,think about $$ vs. comfort and go nuts.

Boilerpro

I'm right on board with Floyd..

I have seen contractor after contractor make this same type of statement..."You have to provide enough heat to get the radiators to 180F". Unfortunately, these contractors are also often the ones that have been in business for years. This belief has been handed down from generation to generation (one of the bad results of apprenticeship training so commmon in this field) and no one along the line ever checked it to be true. I have at my fingertips the "Boiler Replacement Guide" by Weil Mc Lain...a very old and large cast iron boiler manufactuerer here in the U.S. The very first statement under the section titled "Sizing Hot Water Boilers" Is "There is only one accepted method for determining the proper size of a replacement hot water boiler: THE HEAT LOSS OF THE BUILDING MUST BE CALCULATED".

Yes, about 60% of the heat produced by radiators is convection, but that convection begins to occur as soon as the radiator becomes warmer than the air temp around it. If you can, find a building currently heated with hot water heat and stop by on a warmer day. You can easily grab hold of the radiator and tell the water is not at 180F (usually it is well below 140F) and you can feel with your other hand the heated air coming off the top of the radiator. The amount of heat coming off the radiator (both radiant and convective) is in relation to the temperature of the radiator(and the water inside it). The hotter the water, the more heat available, the cooler the water, the less heat available. This relationship forms the basis for hot water heating system controls that automatically adjust the water temperature according to the heating needs of the spaces. These automatic controls have at least a 50 year track record on all types of systems.... including radiators.
Your heating plumber should have concerns with condensation in the boiler (when using "conventional boilers")and it an be easily taken care of using piping and installation techiques that have been known since at least the early 1960's. I work with many old radiator systems and I have not installed a single hot water boiler whose size was based on the radiators capacity to produce heat at 180F. In fact may of these sytems never reach temperatures over 140F on the coldest day of winter, and most of the winter only operate about 110F.
Also, depending on what state you are located, there may be state laws that prohibit the installation of heating equipment not based on the calculated heating load. In fact, one of the most common building codes used for commerical structures also has this same requirement... heating equipment must be sized to the heat load of the structure.
Please find another contractor who has completed the training to properly design and size equipment. It is my guess that your contractor is simply using the same method that he was taught by his/her mentor. He may be a fantastic plumber, but appears to need some training in the hot water heating field. Best of luck!


Boilerpro

Eric Taylor

Engineer's view

This should be good for some laughs right?

I just pulled out my heat transfer textbook from college and reviewed the rules governing both radiation and natural convection heat transfer. To get exact solutions on heat transfer of complex systems requires some really wild math, but the basic laws are pretty understandable.

Boltzman's law states that the energy radiated by an ideal body varies with temperture to the fourth power (T^4th). This means that for a given CI rad, assuming it is ideal, raising the temperature of the surface by 10* will result in increasing radiated energy by a factor af 10,000. The opposite is true as well. Drop the temp by 10* and the radiation decreases by a factor of 10,000. Keep in mind that a small number multiplied by 10,000 is still a small number.

Convection on the other hand is a linear relationship (for the most part),and varies with T. So if the temp of the surface is doubled, the convective heat transfer is also doubled and vice versa. This is not exact, but for this discussion, it will do.

Given this, operating CI rads at low temperatures will effectively turn them into convectors. Saying that CI rads produce 40% or their heat in the form of radiation is probably not true at low operating temperatures. In fact, for the temperatures that a hydronic system operates at, I doubt that it is true even at 200*. Most examples in my book for radiant heat transfer are at VERY high temps (1000* or more).

Another point is that heated air also radiates. With baseboard convectors, the majority of the energy is released by convection (at all temperatures), but that volume of rising air is going to then radiate energy into the space. Even though the energy radiated per unit area is small, picture wall to wall baseboard with a solid panel of warm air above it that covers the wall. The area is maximized.

Hold your hand in front of a CI rad at 110* and I doubt you will feel much radiation. Hold it above that same rad and it should feel a bit warmer. Do it at 180* and you will feel some radiation, but the convection is huge. Just watch the lint and spider webs dance in those rising currents! My personal experience with my house has convinced me that baseboard is second only to "radiant" floor. I put that in quotes because I havent done any calcs on this, but I bet that the proper term would be "convective floor". Things just don't radiate much at low temps.

Something else-- ANY heat exchanger is 100% efficient! I can feel all of you shaking your heads, but it is true. Where is the inefficiency? If the fluid stream is pumping 10,000 BTU/hr through the heat emitter and only 5,000 BTU/hr is coming out of it, where did the other 5,000 BTUs go? To the next heat emmitter, thats where! It dosen't go up the stack, it all goes into the space.

Back to my house. I had CI rads with a modern boiler (see my post on the round table), I was miserable. The rads were hardly warm and the heat rose to the ceiling directly above the rads and then went up the stairs and were lost through the roof (my attic was the most comfortable room in the house). I could stand in the stairwell and feel my hair moving in the currents. All rooms were cold and the fuel bill was nuts, even after I cleaned out the boiler.
Lost the rads and ran baseboard wall to wall with the same boiler. Now my stairwell is the coldest place in the house, my fuel bill is down by half, and we are comfy. Why? The heat is now distributed over a much larger area than with the rads. I still have rising convection in each room, but with it being diffused over more wall area the heat stays in the rooms and does not go up the stairs.

My suggestion is to dump the rads and put a modern system into your house. You can try to sell that old iron, I tried to sell mine to no avail and ended up dumping them. I know you wet heads love those old boat anchors, but I couldn't have been happier to get rid of mine.

ET

Walt

House in Boston

Mark:

We have almost the exact system that you describe. That is, we ran pex from our cast iron radiators to the basement and set up a manifold system. It is a large place, so this was not only intended to help balance the radiators, but we wanted to be able to create zones that could we could turn the temp down in certain areas of the house. We have the various zones on timers so the temp sets back at appropriate times and then climbs back up just prior to when we are likely to use an area.

It works like a charm and is very comfortable. Not only that, we are old house buffs and we did not have to lose our beautiful cast iron radiators.

As I said, we are in Boston. I'd be happy to show you the system if you want to drop by some time. ...if so, make it soon, as I may be off to play in the sand in Iraq soon.

Your boiler guy sounds like he is making up excuses in order to do it the way that he is most familiar with...or he does not understand some

Best regards,

Walt

joel_14

marc

Your plumber hasn't got a clue as to what he is talking about. Where in Mass are you?? We're in Mendon.

Eric Taylor

Numbers don't lie

Just did a quick calculation. Lets assume that we have an ideal radiation surface and apply Boltzmann's law. At 110*F this ideal surface is only emitting .0097 Btu/hr per square foot. At 200*F the same surface emits .0113 Btu/hr per square foot. I checked my units, and the calc is simple. This works for any surface, horizontal or vertical (radiation dosen't care). The calc is flawed only because it assumes a perfect surface. The real surface--be it a floor or CI rad will radiate less. The formula is: E=sigma T^4. Sigma is Boltzmann's constant and equals .1714x10^-8, and the units are Btu/(hr ft^2 *R^4) To get *R you have to add 460 to *F, this is the british equivalent to the Kelvin temperature scale. E is energy of course and the units are Btu/(hr ft^2). The same calc can be done with metric units where energy is in watts/meter^2 and Boltzmann's constant is 5.669x10^-8 watts/(meter^2 K^4) K is the Kelvin scale-- add 273.16 to *C to get K (its not called *K, just K)

I'm sorry folks. Your radiators are really convectors and radiant floor is really convective floor. Convective floor SEEMS like radiant because the heated air is not very hot relative to ambient and dosen't shoot for the ceiling. Also if the entire floor is heated it will be tough to establish convective currents because all of the falling cooler air collides with the rising air. Try putting radiant floor in only half a room. I bet it will get a bit breezy.

We know that heating systems work. I am just saying that the term radiant is rather misleading, and just about all of the heat is being transferred to the space with convection NOT radiation.

Any other imagineers disagree?

ET

Floyd

Your missing the point.....

#'s do lie... in respect to what the human body feels or percieves to feel.....
unfortunately for you there cannot be a quauntative figure placed on those
variables....

Can you place a quanative valve on the relative warmth that the human body
"feels" from the sun??? With radiant it is the same way... we are not talking
a quanative output of warmth... but rather the less tangible feeling that is realized
by the human body when it's surrounding's are warmer the the temp. of the surface
skin temp. of the body.

Yes you are right about radiant being somewhat convective, but you are not going
far enough... there are other values to consider that may be much less tangible and much
harder to nail down...These things are much better taught in the field with relative field
experience.. they cannot be taught or justfied in the classroom.

I'm sure you will say "but what about my house" I say that there are to many other things
that could have changed there that could have skewed your results, and without
an extensive investigation of what you experienced it is impossible to say directly the
your results were totally the result of the change to baseboard......

After many trial and errors...... I can only speak from the experiance that I have obatained
from actually field experience as to what really works and what the most of the people
have been the most satisfied with....

There are exceptions to every rule.......

That's what keeps this buisines so interesting and what separates the "men from the boys"!!!!!

Thanks for your input though, it was interesting!!!

Floyd

Eric Taylor

Your Right Floyed

It is very tough to quantify comfort. I do agree that a warm floor "feels" better than warm air, and a person's perception of comfort will change based on many factors. I also agree that you folks in the business have a great deal more expierence in the comfort end of things than I do, and there are factors that are specific to each situation.

In my posts above, I was just trying to address the methods of adding Btus to a space. This will happen regardless of weather or not people are present to "feel" it. A Btu is a Btu is a Btu. One thing I did change in my house besides the emitters was to heat the attic. This reduces the stacking effect and will slow the convective losses from the lower floors. So there are other factors in play, but with my house anyway the change was like night and day. I doubt that keeping the iron and heating the attic would have had the same effect.

I am trying to find an article that will confirm my claims above, but I keep getting nerd stuff that is REALLY hard to understand.

Steve Ebels

Mark

If it were mine, I would do the following.

Keep the old rads. Regardless of the discussion of convective vs. radiant on this thread, the rads will deliver more comfortable heat. Comfortable tenants are happy tenants.

Put a TRV on each rad to act as a temp limiting sensor when a given room is subject to internal heat gains.

Use a boiler that will take low temp water so those rads can idle right down to nothing on the 40-50 degree days in the shoulder seasons. MMMMMMMMMmmmmm, feels so good!!

Along with this boiler use an outdoor reset control that will regulate the water temp corresponding to outdoor temp. This will limit what the renters can turn the heat up to thereby saving you money.

JMHO

mark_3

okay, so how's this?

I appeciate all of the input and I am learning a lot. I think I am comfortable that keeping the rads is the right thing to do. This brings me back to the boiler one last time.

The question:
Am I right to say that... convection or radiant, pumping 40,000 BTU's into an apartment with rads or baseboard capable of emitting 40,000 BTU's is going create the same ambiant air temperature regardless of how the BTUs are making it into the room?

As for boiler recommendations... I need a heat loss calc done, but it sounds as though I need about a 40,000 BTU boiler per apt. I think I want to do indirect hot water (or tankless?). It sounds as though there are special boiler that handle the lower temp ranges better than others. Any suggestions? I am looking for an energy star rating so I can use the rebate. Anything in particular to look for in this type of application? The local plumbing supply place recommends boilers from new York Thermal Industries that hang on the wall and heat domestic water via a tankless system. I know there are others out there too. They will go in the basement so size isnt a huge factor. Low maintenance, affordability, and high efficiency would be nice!
-Mark

mark_3

in New Bedford

Hi Walt,
Sounds like your system is very close to where I am headed. I am curious as to some of the particulars to you setup. I.e. how does the PEX connect to the rads? Is each RAD brough all the way back to a manifold at the boiler? Any drawbacks to using the PEX or anything else about the system you find troublesome?

If you don't mind me asking, can you describe your system in more detail and what was the cost?

Have a great holiday and best wishes for you and your family as you head overseas.
-Mark

johny

myhead

is spinning.But great discussion.This relates to my later question.Have to study those bypass piping setups.Thanks

ScottMP

My Head is Spinning also

Let me see if I can add my two cents worth out getting lost.

First Mark ; My house has all cast iron rads.. I have a Buderus boiler with weather responsive temp. reset. My system rarely runs above 140 and my house is toasty warm.
Cast iron radiators will stand up to the punishment of a rental unit far better than Sheet metal baseboard. As far as cold return temperatures to your boiler, this can be taken care of in a couple of ways. One would be a high efficient, condensing boiler. Another would be a piping arrangment that would blend boiler water to achieve the desired temp. This could a mixing valve or primary/secondary piping.
Try talking to a different plumber. If you really like this guy, ask him if he wants to try something different. I would have done the same job four years ago. Then I came to this site . Send your guy here and let him ask some questions.

Ed ; Your calcs are way over me, math was my weakest subject, but as Floyd pointed out the human factor here is the variable. Convection or radiant, if your home was cold before and warm now then the original radiation was undersized. You ( I am sure ) did a heatloss on the building and installed the proper amount of heat emmiters to warm the building to design temp. I did'nt see your round table discusion, did you redo the boiler also ? You are correct when you state that insulating the attic would decrease the stacking effect. I find it hard to believe that just the change to baseboard, would slow down the currents you experienced.

If you are delivering the same amount of BTU's per room, whether the air flow was dispered around the room or from a single location, would'nt the air flow still be relative, or equal . The gathering of less dense hot air from the different rooms would be the same and the current in the staircase not effected by heat emmiters ??

If a floor is not truely a radiant heat source and is convection, then why would'nt the air stack at the cieling ? You said it dos'nt feel like convection because the air flow is so slow. No mater what the speed of the air flow would'nt less dense hot air rise to the ceiling regardless ? We have been told that radiant floors only heat the first six or seven feat and does not stack at the cieling. Is this not correct ?

I read your roundtable post now. WHY did you scrape the reset control. Regardless of the above discusion, dos'nt lower water temperarture need less BTU's and therfore less fuel ??? What am I missing here ?

Great Post

Scott ( in the deep end ) Milne

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Steve Ebels

I would never put

A tankless water heater in a situation like that. If you size it big enough to meet the max load, (all the showers and kitchens and so on running) you'll be grossly oversized for the times when only on or two apartments are calling for hot water. When this scenario happens the tankless (unless it has a modulating burner) will short cycle like mad, leading to an early death. Or at the least, high maint costs. The only other solution with a tankless is installing a buffer or holding tank in which case you might as well go to the scenario below.

I feel a better way is to use an adequately sized indirect fired water heater which uses your boiler as the btu source. We did this setup in a new six unit apartment a couple years ago and it works great. The tank is 80 gallon capacity and they have never run out of hot water.

I can give you more detail about this job if you want. Dan wrote an article about it in P&M magazine, or maybe P&M Engineering. I can't remember. Maybe someone has it archived.

We used baseboard due to two things. 1. There were no old rads there waiting to be used and 2, I didn't think of panel radiators at the time. I believe that was the last job I used baseboard on. Don't like the stuff myself. It doesn't hold up well especially in a rental environment.

again JMHO

Boilerpro

40,000 btu/apartment?

That sounds really high, unless each apartment is really big (2,500 sq ft or more) or you have solid walls of single pane glass and extreme air leakage. Just a concern.

Boilerpro

Steve Ebels

Yah, what Boilerpro said.

40K btu's into 900 sq ft gives you about 45 btu's per sq ft of floor space. Sounds high. Again, an accurate heat loss is mandatory!!!

A well insulated structure with good windows will usually run 25 btu's per sq ft or less in my humble experience.

mark_3

Heat loss calc coming

Sounds like 40,000 is too much. I am getting my drawing over to another plumber I met on The Wall to get some more input and a heat loss calc. In case you are curious, I do have four 3.5x5.5 single pane windows plus a large single pane bay window. Ceiling are 10'. The other 5 windows are new low e windows.

-Mark

mark_3

boiler selection

I have been looking around to see if there are any dominant products out there in the <50,000 BTU range and haven't been able to see anything that stands out. The local supplier raves about this new NTI boiler:

http://www.nythermal.com/Media/Docs/Pdfs/NTI_Trinity_Brochure.pdf

But I haven't seen much about it except at their web site. This is a 900+ SF 1BR unit with one shower and one washer. I would like a boiler that does indirect or tankless hot water. I am looking for an energy star qualified unit. For aesthetics (historic home) i would like to vent through the chimney, though if the benefits are there I would consider power or direct venting. I am reusing my CI rads and would like to control boiler temp with an outdoor temp set back controller.

I have been warned about condensation issue on low temp systems but I am not sure what causes it or what to look for in a unit taht handles it properly. I assume the problems are corosion related.

If you have a "favorite" that seems to fit this application please speak up. Also, I have an oil tank left over from the old system... I have assumed I was going to use a gas boiler but should i be considering oil?

Thanks, Mark

kevin

The trinity..

is not a bad choice but I might look into a Munchkin from heat transfer products.Coupled w/ an indirect(60 gallon superstor ultra) would be a slick way to go.(that is if you have natral gas, LP would be expensive) If oil is a choice I might thinktwice about reusing the oil tank if it is more that 20 years old... this is a very interesting disscusion going on. kpc

ed wallace

heat loss

get together with walt pollard i was at his house last week and was impressed with his system ive never been in a victorian that was warm what hes done is amazeing

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mark_3

munchkin vs nti or other

can a temp set back controller be used with the munchkin? Is NTI a respected brand?

kevin

I am not...

the best person to answer that outdoor reset question...I don't see why it would not. The Munchkin is fully modulating so as not to heat up more than needed at that time. The NTI is a good company. It is just new to this area.For more info. check out their web sites. Just put NTI and /or heat transfer products into Google. kpc

Eric Taylor

My House

> is spinning.But great discussion.This relates to

> my later question.Have to study those bypass

> piping setups.Thanks

Eric Taylor

My House

I didn't make the decision to scrap my rads lightly. I did explore several other options before committing to that much work.

I was dealing with a sytem that was grossly over radiated on the second floor and grossly under radiated on the first floor. The system was added to the house as a retrofit sometime after the house was built, and originally burned coal. The house is a colonial circa 1920, and is called a four square. There are four main rooms per floor arrainged in a square. Each room has two exterior walls filled with blown in rockwool that has settled. VERY large windows that are all new double pane replacements (still cold). The siding is in rather sorry shape, and the foundation has very high walls made of field stone. All of this made doing a heat loss calc rather difficult. I did it several times with differen't assumptions as to air infiltration, R value, etc, and even with slightly conservative estimates, the boiler was about right.

The first thing I did was to look inside the boiler's combustion chamber. It was a mess. At four years old, I doubt that it had ever heated above

Eric Taylor

Scott

My original radiation was undersized on the first floor and oversized on the second. I kept throttling back on the second floor in an effort to put more heat into the first floor. It wasn't working to say the least. I did get a bit closer, but we were still unhappy.

The house is a colonial circa 1900 and is called a four square. There are four squarish rooms on each level and the house is also square. Each room has two exterior walls with large windows. The foundation is field stone with high walls about four feet above grade. Blown in rockwool insulation to boot. All of this made for a difficult heat loss calc. I did several calcs with differen't estimates for infiltration, R value, etc and the boiler came out just a teensy bit undersize.

The basement was bitter cold, and with all of that steel pipe uninsulated down there you can guess where lots of the heat was going. Add to this poor placement of the rads and not enough EDR where it was needed and you can see why I was cold.

The boiler was very sick. In its four years of operation direct pumping that system I doubt that it ever operated above the condensation temp. What confuses me is that there was no puddle on the floor. I cleaned it out very well and saw a serious improvement in the output, but it still could not get the temp above 130 without running continuously. Again direct pumping. Running manual control, I could get some of the rooms comfy, but the first floor was still very cold. Switching to primary/secondary pumping would protect the boiler, but it would not solve the comfort issue.

I went and changed out the rads with baseboard. I toyed with the idea of keeping the rads, but comfort aside they were not placed well. Some were on interior walls, some right in doorways. One was outside the nice big closet in the MBR and the closet door opened in! Useless! The pipes in the basement were hung so low that even my wife had to duck under to get to the laundry. After stubbing my toes quite a few times on the rads, I decided to loose them.

I too was dissatisfied with thin sheet metal and searched untill I found Argo Panel Trim. The covers are 16 or 18 gage and they are creased along the length which add strength and asthetics. I kicked one pretty hard on the display in the supply house and it went Bong, but didn't dent. My three year old loves to stand with her feet on the damper plate and look out the window, again no denting or bending (she is about 40 pounds!). I also liked the corregated fins for high output.

I ran the baseboard wall to wall. Over did it in every room! I did calculate roughly what each room needed and made sure I was over installed by a fair margin. The reason is mainly because it is easier to reduce the output of a given emmitter that to increase it, but also because of furniture placement, asthetics, and even heat distribution. I believe that heating the whole wall is important for comfort. With the rads, only one spot of the wall was heated and the rest was shedding cold air like mad. The cold air went straight to the floor (and our feet), and contributed to the stacking effect. By heating the whole wall I have probably increased my losses to the outside, but the stacking has been reduced, and the comfort has really improved. I can walk around with a smoke and watch the air currents. Before the change every rooms' air headed for the stairs. After the change every rooms' air heads for the convectors, and the stairwell is cold.

I tried to keep the reset controller, really I did. I twiddled the knobs for a whole season before I dumped it. It just wasn't doing what the documentation said it was going to do. The room sensor and the outside sensor were reading the wrong temps. Both were reading higher than they should have by about 4*F. What was baffling was the fact that according to the room sensor and setpoint, I was 7*F higher than I should have been and the burner was trying to maintain it! I twidled away to try and compensate and was successfull for a given outside temp, but as soon as it changed I was twidling again! The house temp would also swing with the wind speed due to the changing infiltration rate. At a given outside air temp, my heat loss changed significantly with wind speed, and the reset control wouldn't react correctly even with the room sensor. This got rather tiresome to say the least. Just when I though I had it adjusted right, things would go haywire again. So I dumped it and went with a mercury thermostat. Now if I ask for 70*F, I get it regardless of the outside temp and wind speed. Sure, I have a larger differential, but we are still very happy.

Over time I will tighten up the walls and refinish rooms with new insulation, plaster, and a vapor barrier. I hope to get it done before the boiler needs to be replaced so that the new one can be sized for the new heat loss. I will go with condensing and a modern control scheme when the time comes, but for now things are good.

ET

Terry

delivery an issue?

I am having a difficult time getting any product out of NTI. We have been waiting for boilers since October. (The last trailor was recalled due to bad welds).

An Immediate Advisory has also been issued on the Trinity. It appears that on some installations a "no flow" situation can occur while the burner is on. Not Good. So no mixing valves on supply side. Depending where the Relief valve is installed, a 2nd relief valve may have to be added.

For more information, contact Jason or Kevin @ NTI 1-800-688-2575.

Good Luck my friend.

Terry T

"Everythings better wet!"