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Advice on purchasing a new gas boiler?


First time homebuyer here and recently found out that we will most likely need a new boiler. This is the story. We first moved in and turned our heat up to about 68degrees and found out that our natural gas bill is really high (about 400 dollars.) We were reading other forums and found this is normal for a 3600 sqft house that is heated on every floor. We then tried to turn some radiator valves off and had some success with some and were unsuccessfuly with others. We were able to turn the valves off and we "thought" that the the hot water wouldn't be able to get into the radiators so when we turned the heat on again, sure enough the radiator was warm and now not hot, but some were cold. We also have a 175,000 BTU boiler and has seperate standing pilots for the hot water heater and the boiler.

We had a couple heating "specialists" come in and they said our boiler was fairly new and that it seemed to be working fine. We adjusted the pressure to the correct specifications, nothing more that we could really do, except getting the yearly maintenance done on it and thats where everything goes sour. The technician came down and wanted to take the screw out to do a gas pressure test from the gas valve, but was unable to do so since it was stripped... They said a new gas valve, the box thing before the gas goes into the boiler costs about 400-500 dollars and also mentioned that this boiler is about 20 years old, so probably not that sufficient. We speculated to get it looked at when we checked our meter during the day and the heat at 63 degrees it used about 18 ccf's with not using any hot water, our last bill was $550.

Long story short, we are looking to get a new gas boiler and we are going to get a couple free estimates, but wanted to get a ballpark idea on how much it will cost for a new boiler if anyone here has recently purchased a new one and installation. I know its different for other companies to do it. Also with our radiator valves closed they still are warm when the heat turns on, I also wanted to know if getting a new boiler will help with that or its not worth considering until the valves are replaced and see how much gas we use.

Thanks for the help.

Re: Advice on purchasing a new gas boiler?

I would get at least one more estimate from another company on the gas valve replacement---the estimate seems high & it probably doesn't need replacement.

The shut-off valves on the radiators are designed NOT to shut off completely---there is a lttle hole in the valve inside to allow a trickle of water to flow thru the rad--this is to prevent freezing & damage to the rad.

When you say a 175,000 btu boiler--look at the metal tag on the boiler to make sure you have the OUTPUT btu/hr number and not the INPUT btu/hr number--both numbers are usually printed on the boiler tag.

If the output IS 175,000 btu/hr it sounds a little high than what's needed for the size of your house & would burn more fuel than needed.

Rather than have a replacement boiler put in now (especially during the height of the heating season when everyone is busy), I would suggest waiting til the spring--and in the meantime concentrate on the important other things you can do to reduce your gas bill.

You should take a hard look at the need for any insulation needed in the exterior walls & attic---this stuff is blown in (usually in a day) for a few hundred $$$ & costs a lot less than a new boiler--consider installing an outdoor reset system for a few hundred $$$ (Tekmar 256)---these lower the boiler water temp on "not so cold days" (which comprise most of the heating season) & save money on fuel usage.

You should also scrap the gas hwh for an indirect-fired hwh by Triangle Tube, Weil-Mclain Gold Plus, Lockinvar Squire, Tfi Everhot or Amtrol Boilermate---these units use the boiler's hot water to heat the domestic tap water, so they eliminate the gas usage to heat the domestic hot water---they also eliminate the flue losses that go up the hwh flue---these units. typically 40 gallons in size, cost $700-$1000.

The size of the gas burners inside the boiler can in some cases be reduced (if there is no problem with waiting for heat in the rooms-downrated) to further save on gas costs.

Zone valves/circulators are rather easy to install & are widely used so you can control the temp in the rooms you don't use much---each zoned room or rooms would have its own t-stat to save on gas usage.

I would rather see you spend $3k-$5k on these modifications & keep your present boiler this year to see how much improvement can be realized---all of these modifications are permanent & won't have to be changed if you do decide to get a new boiler later on

If the modifications don't save enough gas, you can buy the boiler over the summer when there is more time to get 4-6 quotes on different boilers---and the installer will have more time to do a better job.

Some of the links below identify the different types of gas boilers, and cost ranges to be expected.


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