Home>Discussions>INSULATION & HVAC>Condensing, Wall Mounted, Gas Boiler...Compatibility with Hot Water Radiators?
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Sombreuil_mongrel
Re: Condensing, Wall Mounted, Gas Boiler...Compatibility with Hot Water Radiators?

As far as a heat loss calc, it may not be necessary if you can read the capacity of the existing oil burner/boiler. It should have a BTU/hr and gallon-per-hour rating on the builder's plate. So, if the old unit was adequate, the new unit of the same capacity will provide enough heat for your home whether gas or oil.
Casey

in.need.of.help
Re: Condensing, Wall Mounted, Gas Boiler...Compatibility with Hot Water Radiators?

Thanks for your reply.

All of it makes sense, and maybe I am just getting in too deep, and complicating things, a trait, I usually can not shake. The plate reads 144,300 BTU's with this information, and with my house being 2200 square feet, some viewers are saying the 144,300 BTU's are way to big. I can not respond to the heat level being adequate or inadequate, as there are 4 rooms in the house where there is electric baseboard heat, which I do not use, however, I believe they were taken out, after this current boiler was installed. So it is cold in those rooms, when it is very cold outside, as they are not heated. Also, I am very conservative with my thermostatic settings. Although where there are radiators I can feel the heat pouring out of them.

The point was made, if this 144,300 is very oversized, or even undersized, to my house, than I may unknowingly be using a lot more gas, or "oil" to keep whatever type of boiler, up to temperature. Hence, the reason for doing the heat loss calculation?

johnjh2o
Re: Condensing, Wall Mounted, Gas Boiler...Compatibility with Hot Water Radiators?
Sombreuil_mongrel wrote:

As far as a heat loss calc, it may not be necessary if you can read the capacity of the existing oil burner/boiler. It should have a BTU/hr and gallon-per-hour rating on the builder's plate. So, if the old unit was adequate, the new unit of the same capacity will provide enough heat for your home whether gas or oil.
Casey

The point is that many old systems were over sized causing poor fuel economy. Your method of just replace what is there with the same size is not the way to go. What's so hard about doing a heat loss?

John

in.need.of.help
Re: Condensing, Wall Mounted, Gas Boiler...Compatibility with Hot Water Radiators?

You make a very good point about needing the heat loss calculation to acurately determine the BTU's of the new system, and I do feel the need to do one.

I have never tried to do one, so I figure I will try, it sounds like your saying it is not so difficult. I figured that the estimators don't do it because it is too complicated? But I see you are saying, it is no big deal.

Do you have any recommendations on sites with fill in forms that are user friendly for me to do a heat loss calculation?

I searched and found form, it I looks like a fill in form, with information I gather, and than the computer does the necessary calculations? Later today I will try to sort through it.

Thanks again for your advise.

dj1
Re: Condensing, Wall Mounted, Gas Boiler...Compatibility with Hot Water Radiators?

in,need.of.help,

This one is a no brainer: you have access to natural gas, you have a lousy heater...replace it.

"Buying time" will end up costing you more, and not only in term of money.

Re: Condensing, Wall Mounted, Gas Boiler...Compatibility with Hot Water Radiators?

Switch to natural gas if you can. It is way cheaper than using oil.

A mod/con boiler will work very well with a system like yours. However, it may not be worth the extra cost over a conventional boiler. Mod/con boilers do require a cleaning every year. You also need to have low return water temps to keep the boiler in the condensing range. You will not have the 95%+ efficiency unless it is condensing. However, it is very likely that you can achieve that with an old system like yours. That were always way over sized. Especially if the home has had insulation added. Another option is a boiler like the Burnham ES2. It can handle 110F return water and has an optional outdoor reset available. This is a conventional cast iron boiler and doesn't require the upkeep that a mod/con would. They have another version of this boiler that is sealed combustion too.

This is what you need to do. Get a heat loss done. I used hvac-calc.net to do mine. It cost like $50 for a few months of use. Slantfin offers one for free. You should never size the boiler based on the amount of radiation in your home or based on the size of the previous boiler. If your current boiler was not in such dire circumstances, I would insist you insulate first, but you may not have the opportunity to do so.

For hot water, get an indirect hot water heater. The built in coils are the worst way to make hot water. The indirects last a lifetime and have a faster recovery than a direct fired water heater.

Check out www.comfort-calc.net . There is a lot of great information there about mod/cons and heat loss calculation. Also see: http://www.colonialsupply.com/resources/radiator.htm to determine the output of your radiators. This will help you figure out what water temperatures you will need to heat your home.

in.need.of.help
Re: Condensing, Wall Mounted, Gas Boiler...Compatibility with Hot Water Radiators?

Thanks so much, it looks like you have offered a lot of useful information, it is all very much appreciated.

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