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Condensing modulating gas boiler?

Our Weil-McLain gas boiler has been operating with few problems, but it's now over 20 years old and its efficiency is relatively low. With monthly gas bills climbing over $700 in the colder months, I'm thinking that it's probably time to start considering a more efficient alternative. I've heard about condensing modulating boilers that provide over 90% efficiency, but other than having heard that the Triangle Tube Prestige boilers offer a good combination of value and reasonable installation, I know little about these things. So I'm wondering about the pros and cons of going this route, what brands I should consider, and a rough idea of what costs are involved in making the switch (including any federal tax credits or rebates that may be available. My house is a 40-year-old colonial with about 3,300 sq. ft. in Southern Connecticut. All suggestions greatly appreciated.

Re: Condensing modulating gas boiler?

Yes, the Triangle Tube Prestige is a great boiler & is rated at 92% efficiency, but could you provide more info as to the model # & output btu/hr listed on your Weil-McLain name plate.

Have you had a recent combustion analysis done to determine the present efficiency of your current boiler??

Have you had an energy audit done to determine if the house is losing heat to the outside due to lack of insulation, etc.

What is the condition of the other factors that would affect how much gas you use in the winter months, such as double-pane windows/storms, adequate insulation of R19 in the exterior walls and R40 in the attic??

A heat loss calculation for that size house would roughly be 132,000 btu/hour, but could be much higher if more insulation needs to be blown in or the windows are drafty.

Other excellent condensing modulating speed/boilers with outdoor reset are made by Viessmann Vitodens, Buderus GB142, Burnham CHG, Biasi, Utica UB 90-200, Dunkirk Quantum, Crown Bimini, Peerless Pinnacle, Hydrotherm GX, NTI Trinity & Weil-McLain Ultra.

If you live in an area with hard water, a unit with a combustion chamber of stainless steel rather than aluminum is recommended.

Viessmann & Buderus and a few others are considered top of the line from European mfgrs, they tend to cost more due to the dollar/euro exchange rates, but they are very good units.

It's equally important to find a knowledgeable, experienced installer in your area who knows the equipment & knows how to install it---a good installer who is familiar with what will work in your building will put in a top rate unit for less expense that will have you see a drop of 30% in your fuel usage---get at least 6 different estimates, the choice of brand & model and price quote will vary highly from each installer.

Get some quotes also from oil dealers---they are all licensed to install gas heating equipment & often charge a lower price--check with your local heating parts supply houses, ask the counterman to recommend an experienced installer in condensing/mod installs.


Re: Condensing modulating gas boiler?

Thank you for your prompt response. The Weil McLain model number is CGM-6. Its output is 140,000.

I have not had a combustion analysis or had an energy audit other than by the company that installed central a/c a few years ago. Some parts of the house have been gutted. In those areas, we put the heaviest insulation that would fit. But there are also rooms where the original thin insulation is still in place. The attic is not insulated. It's a peak roof attic with vents at either end. I suppose it could be insulated in-between the rafters, but wonder whether we should close up the existing vents and then install a ridge vent.

Most of the windows are less than 10 years old with double-glazing. There are still a few older windows with exterior storms. I plan to replace the sashes this summer.

Our water is quite soft.

I suppose the best time to explore the options would be during the summer. I'll follow your suggestions about getting estimates.

Many thanks.

ulaRe: Condensing modulating gas boiler?

Any insulation that has to be blown into the attic or walls should be installed now---before the new boiler is ordered---by all means have the FLOOR JOISTS of the attic filled with insulation to R40---it is adviseable to leave any attic vents open, even in the winter, so that ice dams don't form at the eaves due to uneven roof temperatures.

Adding attic insulation now will save you many heating $$$ in the coming years.

Re: Condensing modulating gas boiler?

Does anyone have info on the quitest models. The install location is on the wall adjacent to our bedroom. Quiet would be nice

Re: Condensing modulating gas boiler?

cskins - i think that most of them are designed to be quiet so that they can be put in rooms next to you without being a nuisance to the person.

NashuaTech - Is the Landlord Insurance Tube Prestige the highest rated efficiency at 92%??

Many Thanks

Re: Condensing modulating gas boiler?

Mea culpa---the Triangle Tube Prestige Solo is rated at 95% AFUE; it's also listed as a quiet unit--I must have taken the lower figure from a much older, outdated list.

Yes most new units are quiet, but I would get that stipulation in writing as part of the installer's bid if the unit is to be placed next to a bedroom.

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