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I am considering installing a small 20 gallon electric water heater in series with a 40 gallon gas water heater and am curious if it is considered safe and if it would be to code. I cannot see any reason that it would be unsafe but may I'm missing something.
Reason is to have instant hot water in a location far from the gas water heater, yet I would rather not run the electric one more than necessary. I'm going to have this 20 gallon electric water heater on hand for nothing so I'm trying to find a creative use for it. I am currently using it as a temporary source of hot water while doing other work.
Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment