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Antique Under-Floor Radiator Issue

Hi all --

My Parents' house in Boston was built in 1913 and has a forced hot-water system (previously most likely steam). The first floor has several under-floor radiators that are located in asbestos-insulated duct boxes in the basement. The problem is this: These boxes are connected, via large duct work, directly to intake registers outside of the house. As the radiators heat, the rising heat pulls in fresh air from outside (convection?). The problem is, of course, that a tremendous amount of energy is required to heat the freezing cold air enough to keep the house comfortable.

It seems to me that the duct work should be reworked so that it feeds filtered return air from either the basement or main house to the radiators, thus reducing the radical temperature difference between the heated air and the intake air.

Does anyone have any experience in this area? What is commonly done to make this kind of system more efficient?

Looking forward to any assistance.


Blue RidgeParkway
Re: Antique Under-Floor Radiator Issue

its called indirect hot water (or steam) heating. i'll put a link you to an article that explains it.

usually by getting a certified asbestos removal contractor to remove the asbestos, sealing the house back up, refitting radiators (direct) or some other hydronic heating system, usually downsizing the boiler or resetting things to run efficiently, and installing a heat recovery ventilator with or without a dehumidifier (necessary as you seal up the drafty old house with modern insulation and caulking, etc. to prevent condensation and ventillation problems in cold-weather climates).

article link: http://www.heatinghelp.com/heating_howcome2.cfm

Re: Antique Under-Floor Radiator Issue

Thanks for the info. That's an amazing link -- addresses the exact issue. I'll definitely pick up the book.

I've been trying to get my parents to improve the efficiency of this house for many years, but they don't have or want to spend the money. It needs new windows and insulation, but given the size of the home, this would be an astronomical cost and disruption.

Maybe we can find a way to reduce the heating bill by circulating different air through the indirect system.

Blue RidgeParkway
Re: Antique Under-Floor Radiator Issue

your welcome for the link.

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