Author Topic: Help with natural gas conversion  (Read 1197 times)

js625

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Help with natural gas conversion
« on: June 10, 2014, 08:46:18 AM »
We are about to have a natural gas line installed in our house, and I am looking for options on what kind of gas boiler to use.  We already have an indirect water heater, and the house uses forced air (two zones) heating.  I can't seem to get a straight answer online on what kind of boiler to get.  I have heard that the 95% efficient boilers can be a pain in the butt to maintain, and was wondering if anyone had any experience with these.  My plumbing knowledge is very minimal and my contractor doesn't seem to want to recommend a specific unit. 

The local gas company offers an incentive program to get Burnham units that range from $800-$1500 for 86%-95% efficient units.  Any help would be appreciated!
« Last Edit: June 10, 2014, 08:48:10 AM by js625 »

Greg

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Re: Help with natural gas conversion
« Reply #1 on: June 10, 2014, 09:53:49 AM »
What's the boiler for?  Heat?  Hot water?  Both?

Prairie Stash

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Re: Help with natural gas conversion
« Reply #2 on: June 10, 2014, 11:17:21 AM »
Gather up the gas bills, figure out how much gas you used last year.  If your current furnace was 80% efficient that means if you paid for 500 cf then 400 went to heating your house (500x0.8). You'll still need to have 400 cf heating your house after you put in a new furnace. if the new furnace is 95% efficient you'll buy 400/0.95=421 cf.  That's without considering the water heater, it's to illustrate a point.  Make sure the increased cost of the better furnace is worth it. That should help narrow it down between the Burnham units, in my example that amounts to 44 cf/year, how much would that add to your bills? Apparently it will cost $700 to save the money.

Remember gas will get more expensive some day, there's some debate on that currently.  Shale gas has really made home heating with gas cheap, hopefully this lasts 25 years. In the past 7 years my bills have gone down 30%, without any changes from me. I can't promise that gas won't spike and make you wish you were more efficient, but I also can't promise it will go up before you need a new furnace anyhow.