Upgrade 1965 Peerless Gas Boiler To New High Efficiency Boiler - Worth It?

Old 11-04-14, 03:00 PM
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Question Upgrade 1965 Peerless Gas Boiler To New High Efficiency Boiler - Worth It?


My home still has the original 1965 peerless gas boiler that was installed and it still works fine.

However, I was just wondering for people who have replaced their old gas boilers with a new high efficiency boiler what type of cost savings did you see yearly?

If it costs me $5K to get a new gas boiler installed, and I'm only saving $150/year on my gas bill it doesn't make sense to do this update right now since it will take me 34 years to recoup these costs. I'm just trying to see if the savings would justify the up-front costs for a new boiler.

Thank you!
Old 11-04-14, 03:35 PM
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Seems you've already got the numbers right, what more do you need?
If that boiler is in good shape, I'd leave it be unless you have 5k bucks burning a hole in your pocket.
Upgrading the insulation and air sealing in your home will pay you back much quicker. Look for the energy savings elsewhere.
Old 11-04-14, 03:53 PM
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If it costs me $5K to get a new [high efficiency] gas boiler installed
Uhhh... no, ain't gonna happen. Try more like $7-10 K. You would be lucky to get a STANDARD efficiency boiler installed for $5K in NJ.

In order to reap the benefit of a high efficiency boiler, meaning a 'modulating-condensing' boiler, you need to be able to heat your home with cooler water. Cooler water meaning never more than say 155F maximum going out, and 135F maximum coming back.

Heating systems designed for conventional boilers use 180F as their design point. Durning the coldest days, you will need 180F water to heat your home.

PART of the winter season you will gain benefit of the higher efficiency because in the warmer 'shoulder' part of the season, you probably WILL be able to heat the home with cooler water and the boiler will operate in the 'condensing' range which is where the extra efficiency is gained.

The way the extra efficiency is gained in this type of boiler is by 'condensing' the flue gas and extracting the extra few percent of heat from that flue gas.

Once the weather gets COLD, you will no longer be able to heat your home with cooler water and the extra efficiency of the high efficiency boilers 'goes away' because the boiler will stop condensing once the water needs to be hotter. They will only condense when the water returning to the boiler is 135F or less.

Add to all this the fact that 'mod-con' boilers require ANNUAL maintenance which generally amounts to around $200 for the service call... and you better HOPE that you get a tech who knows WTH he is doing, which isn't likely these days.

You can buy a lot of insulation and caulking for that kind of money. Those things are fuel that you only pay for ONCE.
Old 11-04-14, 04:14 PM
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Here is a sample calculation. I burn about $1,000 worth of natural gas per year for space heating. Let's be optimistic, and assume that I could save 20% with a new boiler - that's $200 per year. If I demand a 5-year payback period, I could afford to pay just $1,000 for the new boiler, installed. If I would tolerate a 10-year payback, then I could pay $2,000.

Here is a basic truth: It is never economically justifiable to replace a working gas-fired boiler on the basis of fuel savings. Now, if your existing boiler splits open and has to be replaced anyway, you might compare replacements with different efficiencies, and make an informed choice.
Old 11-04-14, 06:36 PM
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Does your system have asbestos insulation? If so, go past GO and PAY a couple of additional thousand dollars.

In replacing a boiler, there will always be some add-ons - e.g., new valves, expansion tank, controls, re-piping, electrical, removal of the old boiler, etc. And, if the replacement boiler is more efficient, codes may likely require you to potentially reline the chimney.

How much longer do you expect to live in the house? How much would these upgrades add to the selling price of the house? What if you bail out before they are paid off?

Saving $200 per year on heating fuel, for me, needs to be compared to other costs. Much less than what I pay for driveway snow removal or lawn care. There seems to be something about energy costs that raises peoples' awareness more than other things.

Last edited by gilmorrie; 11-04-14 at 07:21 PM.

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