Winterizing hot water heat systems

General topics about all things heating, ventilation, air conditioning and refrigeration.

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Winterizing hot water heat systems

Post by TJay » Tue Sep 20, 2011 8:55 pm

General question about winterizing plumbing in homes that have a hot water heating system (any type of hot water boiler or geothermal system for hot water baseboard or radiant floor heat). Almost any heating system I have seen that circulates hot water for heat will have a make-up water supply line from the plumbing system. I live in an area (Western Montana) that has a lot of snowbirds, that own property here, but often leave for the winter. Most of them perform some degree of winterization where they at least shut off the main water supply (typically a well pump), and often have the plumbing blown out to prevent freezing water lines.

Question - how much water do most hot water heat systems need to draw from the make-up water supply during a 6 month period? If the plumbing water supply is completely shut down, and the hot water heating system left running (usually at a low temp), will the hot water heating system be starved for make-up water?

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- Winterizing hot water heat systems

Post by Beach » Wed Sep 21, 2011 10:56 pm

it depends. If the water loop is closed , and assuming you have no leaks then very little.... But like a loop in a chill water system water does seem to "vanish". If you are looking for winterizing the line then i would suggest looking into adding a little glycol in the loop to prevent freezing. Im not sure of the name but there is a envio friendly one out there.

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- Winterizing hot water heat systems

Post by dave34 » Sun Sep 25, 2011 10:57 pm

I think the name you're thinking of is Propylene Glycol. It's generally safe for waste water systems, toilets and hot water heating systems of homes that are left unheated.

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