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Old Hot Water Radiators-Tankless available?

We have the old American Radiator hot-water heat system in our very old house. Is there any such thing as a tankless boiler available such as the tankless hot water heaters?

I know the hot water heaters don't heat water high enough to work. It just seems like there should be something available in radiator heat, though.

Thanks for all input.

Re: Old Hot Water Radiators-Tankless available?

There are high efficiency boilers that do not store water. When rehabbing my house my father installed a propane fired Munchkin boiler that is between 91 and 96% efficient depending on where you set the temperature. I have radiant heat but I would think it should work with radiators as well. They are not cheap though but it will eventually pay for itself. I live in a 900 sq ft house and use propane for heat, hot water (tankless water heater), and cooking and use about 300 gallons of propane a year. I also had the house insulated with foam insulation so that really helps too.

So you have to consider do you want the initial cost of the boiler probably in the 2500-3000 dollar range not installed depending on the size of your house. What type of fuel you already have, and how well your house is insulated. Not sure if they make an oil fired boiler. Anyway I hope this helps you out.


Re: Old Hot Water Radiators-Tankless available?

sabo4545 (Mike),

Thanks for the reply. We have natural gas.

Do you know the name of your unit? I'm not having much luck finding what I'm looking for. If I could get a general direction, I could call some people and get a definite direction.

Presently, we burn mostly wood in a wood stove. However, I'm looking toward the future when cutting and stacking wood won't be so simple to do. So, yes, I think probably the expense now while we have the assets to do it is definitely something to consider if it will save considerable money in the long term.


Re: Old Hot Water Radiators-Tankless available?

I have the Munchkin T80M boiler (yes Munchkin is the name of the boiler). It is made by Heat Transfer Products. They are out of Massachusetts and their website is http://www.htproducts.com/

If you have a good plumbing supply place in your area I would also recommend that you check with them to see what they would recommend for you. I'm sure that there are other companies out there that make similar boilers. Two great things about the boiler that I have aside from the fact that it is very efficient is that it is very small (they actually have one you can hang from the wall). I was able to put mine under the basement stairs so it takes up no room. Also it is a direct vent so it is vented without a chimney (through schedule 40 PVC pipe) and brings fresh air in from outside so it does not use air from the house.

There are a few people who are plumbers on here so hopefully they will weigh in on the question because I am just speaking from my experience with my boiler. Hope this helps you out.


Re: Old Hot Water Radiators-Tankless available?


You actually have a lot of choices in boilers if you decide to keep your cast iron radiators---and I hope you do---radiators are a great way to heat a home---there's nothing like the radiant warmth coming off a hot radiator on a winter's day.

Many people don't realize that cast iron rads are a form of radiant heat---1/2 the heat from a rad is radiant heat, the other half is convective heat---and once a rad heats up, it stays hot for hours---you won't see that with baseboard or other forms of heating.

The only slight downside is that rads are not as fuel-efficient as sub-floor radiant heat, where tubing is strung up under all the floors of the house and hot water at the 100 degree to 120 degree level is pumped thru the plastic tubing---this assumes you have access to the undersides of all your floors---& many people don't in a finished house.

Cast iron rads are designed to operate at 180 degrees, which puts a dent in efficiency, but is a great-feeling heat.

The rads would have to be run with 120-130 degree water in order that the boiler condense & be fuel efficient.

In addition to Munchkin, I would encourage you to look also at 3-pass boilers (88% efficient), Peerless WBV,Biasi Riva, Slant/Fin Eutectic, Energy Kinetics System 2000, and standard cast -iron boilers that are much less expensive & still return 83-85% efficiency.

If you have one or two persons in your family, these boilers have a tankless coil that delivers hot tap water as well---if you need more hot tap water, a 30 or 40 gallon indirect hot water heater that runs off the boiler & uses no additional gas or propane is strongly recommended.


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