# Tankless hot water heater during winter when water shut off



## wctekkk (May 29, 2012)

http://www.rinnai.us/documentation/downloads/V_Series_Indoor_25xx_U245-3250x0100_revised_A.pdf

Page #37 explains what you want


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## jdabs (Jul 9, 2012)

Thanks for the reference, but I read that before posting, and I still had these questions.

The manual says: "If the Rinnai water heater is disconnected from either the electrical supply or gas supply, or if there is an error that prevents the water heater from functioning normally, there is NO FREEZE PROTECTION. Freeze protection of the water heater is only possible when electricity, gas supply and normal water heater functions are enabled. If you expect freezing conditions while either electricity or gas supply is interrupted, water must be completely drained from water heater..."

I still don't know whether the gas and electric MUST be turned off if the water is turned off. Is leaving the gas and electric on if the water is off bad for the heater? Is that what they mean by "normal water heater functions are enabled"?

It also doesn't say whether the type of draining system on the house is enough of a "complete drain" to protect the water heater if the gas and electric are turned off.

Any further guidance? Thx.


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## aquatekplumber (Jul 10, 2012)

very interesting discussion 

http://www.gas-safeplumbers.org/eastlondon.php


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