Soon to be using coil for DHW....drain the electric heater tank?

[muncybob]

The electric water heater and the wood boiler were both new to us last year. After shutting down the electric tank and using the boiler's coil all winter and most of the spring we had a foul odor from the electric heater once it was put back in use that required us to totally drain the tank and refill.
Are there any pros or cons to draining the electric tank once it's taken out of commission for this winter or should it maintain water until next spring for another draining?

 

[parkini]

If you drain the tank you could greatly shorten the life of you tank due to corrosion. Maybe you could leave the tank filled and use some sort of water treatment while the tank is not in use?

 

[vvvv]

drain it. Tank has glass lining within. stagnant water can grow bacteria

 

[jeff_t]

What about running hot water into your water heater? The electric will just have to maintain, won't use much electricity. That way everything will keep flowing. No experience, just a thought/question.

 

[tom in maine]

Unheated electric hot water heaters can grow Legionnaire's disease. I would rather drain it and let it dry out than deal with any biological growth.

 

[juddspaintballs]

Why not plumb the domestic hot water to cycle through the water heater rather than bypassing it? All you'd need to do is flip off the electric to the water heater (if you wanted to) or you could leave it on just in case your wood boiler fire went out and you weren't home, it would keep the boiler from freezing.

 

[tom in maine]

The standby loss on an electric hot water heater is the biggest issue. If one wanted to keep the tank online, a small in tank hx with a small bronze circulator pump could be used
to keep the tank hot. I would rather lose the electric tank until needed.

 

[juddspaintballs]

Wrap some extra insulation around the water heater. If he's using a sidearm exchanger, it should keep the entire tank warm by convection. Standby losses should be minimal.

 

[tom in maine]

I would be skeptical about getting adequate through a sidearm hx from a tank into another tank unless the electric tank is higher than the wood boiler tank.

For what it is worth, I would just go with a single hx in the boiler tank and keep the electric in case you need it.

 

[bigburner]

This what I do in two different buildings, I have a 200 gal tanks with u-tube HX's - Bell & Gosset --I think. Any way run the boiler water threw the HX full time during the season, then domestic water goes into the same tank and then to the gas water heater. There is an aquasat on the boiler line which turns on pump that is connected between the two tanks [couple check valves also] When not using boiler, the pump is off, and the 200 gal tank is just a big part of the water line at that point and nothing has to be done spring or fall. Kinda automatic.