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Maintenance requirements on High Efficiency Boilers

Hi - I thought I had it all figured out, and was ready to hire a plumber to replace our heating system, when I ran into another plumber who had some conflicting advice for us.

I had decide to get a very high-efficiency boiler, the Burnham Alpine. The other plumber said that cast-iron boilers are the way to go, they are more reliable, require much less maintenance, and last much longer. He said the Alpine needs to be disassembled every year and cleaned, whereas a cast-iron boiler needs only a triennial cleaning. He also said that the heat exchangers were not as durable, and we'd be looking for another heating system in 15 years time.

Is there any truth to this? I can't get much help from the boiler's user manuals or the manufacturers contact line.

Thanks so much

Ron Rothenberg
Exclusive Buyer Broker
[email protected]

Re: Maintenance requirements on High Efficiency Boilers


Yes, you'll find quite a bit of variation of opinion on a new boiler choice; that's why you should get 4 to 6 recommendations before you decide---it all depends on several factors, such as the size of your house, the type of convectors present (radiators, baseboard, radiant floor, etc.), how long you intend to stay in your present home, how much you feel comfortable spending.

Consult neighbors, friends, co-workers as to someone they can recommend for a good boiler install; put up a note on the bulletin board where you work; consult the Yellow Pages under "Heating Contractors" also consult the Yellow Pages under "Oil Dealers","Oil,Fuel",and "Oil Burner Service"---oil dealers are also licensed to install gas-fired equipment & often charge less for the job.

It may be best to spend $1k on improving the insulation in the external walls (R19 recommended) and attic (R40 recommended); this will go far, even if some insulation is present, in fuel savings, as well as replacing any windows that are not twin pane or storms---spend $$$ in these two areas first.

A high eff. boiler will probably cost $8k & the 1st 6 mos. will require periodic intervention by the service tech before everything runs correctly; you may qualifty for up to a $1500 energy star rebate, but that's still a lot of $$$ if you intend to move within a year or two, as the savings won't be realized for much longer than that.

If you have cast iron radiators or aluminum fin baseboard, these types of convectors were designed for 180 degree temps to keep the house warm---many people feel uncomfortably cold if a condensing boiler is used (typically with an outdoor reset) that keeps the water temp in the pipes at approx. 120 degrees; this tends to save fuel, but condensing boilers do better with radiant floor or radiant slab heat where a lot of heat BTUs are stored in the wood or slab over an extended period & are more able to keep the house warm with the onset of a cold snap.

The installer who mentioned a cast iron boiler thus may have a point well taken: there are 3 basic types of boiler; the 1st is the basic cast iron reliable workhorse of the industry that sells for approx. $3k installed and has approx. 83% efficiency & may go a year or so without needing cleaning; 2nd is a 3-pass cast iron boiler that has an improved combustion chamber with same cleaning schedule selling for approx. $4k installed with approx. 86% effic.; 3rd is the condensing stainless steel/aluminum boiler at 95% eff. costing approx. $8k installed---that's why the 2nd installer asked you to look at cast iron boilers.

If you don't have one yet, these boilers come with a companion indirect hot water heater ($2k-$3k installed), strongly recommended for the domestic hw; indirects will last for decades with few if any problems & you'll never run out of hot water.

Don't get hung up on boiler efficiency ratings; the condensing boilers do best with radiant floor heat or slab radiant heat, which return good fuel economy, but can also keep the house comfortable because of the way the heat is stored in the wood or slab & is delivered to the living space.

It is noted that the Burnham Alpine is considered more difficult to clean & keep clean than the excellent Triangle Tube Prestige Solo or PE110; the Triangle Tubes have a different configuration to their combustion chamber that makes them easier to clean.

Re: Maintenance requirements on High Efficiency Boilers

I agree with some of what Nashua posted by there is alot of parts that I disagree with.

In making your choice of contractor or choosing wich contractor has the best advice there is only one thing you need. Who did the heat loss? Who did it room by room and along with measurement of existing radiation will design with the correct heating curve.

A condensing boiler does not send a fixed water temperature nor does it fire at a fixed rate. A typical cast iron boiler sends the same water temperature through the system no matter what the temperature is outside. You only need the hottes water on the coldest day of the year. You don't need 180 degree water when it's 15, 20, 30, 40 degrees outside you only need it at your climates coldest day and in some cases you never need it.

I have designed and consulted on hundreds of condensing boiler installations with fin tube baseboard. As an example, I was on a job yesterday going over the Viessmann Vitodens boiler with the homeowner that has been running for a week. It was 33 degrees here yesterday and the boiler water temp going through the system was 110 degrees. The boiler was also only firing at it's lowest rate of 31,000 btu's. Your cast iron boiler cannot do that.

The rule of thumb formula for fuel savings utilizing water temperature is. For every 3 degrees you can run a heating system below 180 degree water you can save 1 percent of fuel. With that in mind, yesterday this customer was saving probably 23% in fuel over you and we haven't taken into account the less amount of btu's this homeowner is using over a conventional beast that is chugging at full input.

As for maintenace, a condensing boiler needs no more maintenance than any other boiler. While boilers like the Alpine, Munchkin and others that use a Gionnoni heat exchanger are a pain to service there are others like the Viessmann Vitodens 100 and Triangle Prestige that are very easy to service. How much do you spend a year servicing your automobile, which is the worst investment any of us make?

Here is a link to a post from Heating Help that has a study that was done by Brookhaven labs. It was too large for me to upload the PDF here.


Best of luck

Re: Maintenance requirements on High Efficiency Boilers

thank you both very much. I am grateful for your efforts on my behalf.

How do I get a heating spe******t who will do that evaluation?

I now have oil heat, and was trying to replace a very old oil system, but couldn't find an installer interested in determining the heat loss, etc. They just would install a too-big system, and that would be it.

So, I gave up on oil, and now I'm having similar troubles with gas. I don't feel much confidence that I'm going to get a right-sized, properly-chosen system, and local advice has not been forthcoming.

thanks so much for your excellent answers.

Exclusive Buyer Broker
Belmmont, MA

Re: Maintenance requirements on High Efficiency Boilers

I would check to see if there is a local trade association in your area. Groups like the Radiant Panel Association or the Plumbing, Heating, Cooling, Contractors Association. You can generally find real good (I didn't say cheap) contractors that have plenty of experience.

You could also call the manufacture and ask for the local rep of their product. They should be able to help you find a qualified contractor. If this is natural gas in some cases there are utility rebates and some utilies require that contractos register with them in order to offer such rebates to consumers.

You could call Viessmann (www.viessmann-us.com) in RI if your interested in their product or Triangle Tube (www.triangletube.com) in NJ.

I've always stood by the point that any piece of equipment can only perform based on the design and installation. The design part in most cases is maybe more important than the actual installation. Without it the piece of equipment cannot perform to its peak ability nor last its life expectancy.

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