Hi efficiency wall mounted boiler ?

[snyder]

A friend just hooked up a radiant floor system in his garage. He used a Bradford white high efficiency gas fired wall mounted boiler.
My home has a gas boiler feeding hot water radiators. The boiler is 25 years old.

Would a high efficiency wall mounted boiler be a good choice for my home?
It sure looks easy to install. Also would I use the btu rating of my current boiler to size the new one? It works fine tow heat our home.

 

[Dagny]

I will probably be called a dinosaur for this but I don't like them. your old boiler right now is better than any new hang on the wall boiler. There is absolutely no chance of one still in service 25 years from today. If one guy can bring your boiler in the basement tell him to get it out of here.

 

[yeldogt]

What kind of radiators ? How much do you spend on heating the property ?

With a high mass system -- cast iron radiators. Fired with NG --- Using an "old school" cast iron boiler is IMO the way to go. Yes, you lose some efficiencies ... but, they run forever and typically do so with little maintenance.

In many cases the savings on NG will only be a few hundred dollars per year going to the high efficiency unit -- you will never get the payback. Also -- the wall units will not deliver those efficiencies firing at high temps that radiators require .. they require low temp return water to "condense".

 

[Jackfre]

If you have hot water baseboard heating there is little benefit to the wall hung as YD pointed out. They generally run at 180* and to get the best out of a wall hung a radiant (low temp) distribution system is best...and you do have to maintain them on their schedule. As well you will have mass quantities of condensate to dispose of. As to matching the size to your old system, most central heating equipment is oversized by a mile. I would stick with a new Weil-McLein, Buderus or Peerless cast iron boiler. They are all tried and true. If you are doing this you will also have hot water to include in the equation. You could add an indirect off a new boiler.

 

[snyder]

I have cast iron radiators. The problem that started all this , is my chimney was constructed without a liner, just concrete parged block. Circa 1945. Now there is a lot of delamination going on. If I go with a condensing system , I was hoping to kill two birds. No chimney anymore and a cheaper gas bill. The upfront cost of a new system doesn't bother me. I will be doing the install myself. So I figure the labor savings will pay for the extra cost of a condensing system.
Thanks for your advice.

 

[Jackfre]

You can run those radiators at a lower temp and will have programming flexibility on the temperature. Research your condensing boiler choice. Go with a manuf that actually MANUFACTURES the boiler and has proper tech support for it. B-W does not build a condensing boiler. I think they, and a number of other companies, private label the Korean Kiterame unit. I am not certain of that, so please confirm prior to decisions. You could eliminate the chimney by going hi-eff. You could also simply drop a proper size liner or a new B-vent down the existing chimney. If you can install a boiler this too would fall in your capabilities.

 

[yeldogt]

KISS ..... What's your yearly heating bill ? How big is your current boiler? What's the heat load of the building? What do you use for heating domestic water?

Getting all of those numbers together --- you will see if your current boiler is too large ..... you will see how much for potential savings.

On my new build I'm so restricted with space that I have no choice but to use a small condensing boiler -- plus my new place is almost all radiant and I have to use propane. If I had space and NG ---- no question I would have used a chimney based Buderus CI boiler and outdoor reset controls. I always do an indirect tank off the boiler.

I agree with jack -- get a boiler from a true manufacturer. Remember -- you will most likely not get much .. if any assistance from them.

You can use a metal liner in the old chimney.

my memory is my friends house with the conversion used twin Buderus wall boiler and the mixing valve controls and headers ... this way the boilers could fire and the radiates could still get the high water flow needed. He saw savings jsut from the better controls -- but he moved from huge oil fired units.

 

[Firebrick43]

How about a Weil Mclain gv90? It's a ci boiler with a condensing unit on the side. You could then have the PVC chimney but the advantages of a CI boiler matched to radiators. Its some what more efficient, more due to cumbusting outside air therefore not bringing in cold outside air into the house.

 

[Jackfre]

Whichever way you go, make sure you have a very clear understanding of the venting requirements and the cost of the various materials which you may use.

 

[Orionrising]

Metal chimney liners are cheap online like 1/4 the price I was quoted locally.

Sent from my Moto G (5) Plus using Tapatalk

 

[HoosierBuddy]

I'm not 100% sure where the hating on fully condensing boilers is coming from.

I installed an NTI one in 2006. To date it has needed a new igniter.

Other than that...no issues. This is a fully condensing modulating natural gas model 150,000 BTU/HR.

Phil