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Water heater unused for a extended period of time: Should it be drained?

Water heater unused for a extended period of time: Should it be drained?


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Old 03-01-17, 04:46 PM
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Water heater unused for a extended period of time: Should it be drained?

We live in a "double" in the upper flat. The lower is now occupied, but will be vacant before the end of the end. I expect it will remain vacant for a period of time (unknown how long).

The question is, other than shutting off the gas valve, should the tank be completely drained, or show it remain full?

I do 'flush' it ever so often (between 1 & 2 years). The tank is 3 or 4 years old, it doesn't have a high demand for hot water at present (if that matters).

Pros & cons??
 
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Old 03-01-17, 06:08 PM
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I don't think it would make a difference one way or the other. But my gut feeling tells me I would keep it full. If only to prevent mold and mildew from forming in the moist but empty tank. Ideally can't you flush about half the tank and re-fill every few months. And that brings up the question of the rest of the plumbing. Will it also go unused? Will the lower flat need to be winterized? If people will be living in the upper section, can't they be "hired" to periodically run the taps, flush the toilets and flush a gal or so from the tank?
 
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Old 03-02-17, 04:48 AM
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Isn't flushing half every few months really excessive?? Water rates are expensive here, beside that seems a huge waste. How about a short flush once a year as most recommend?

As far as the pipes, yes no use planned (vacant, no one to use them).

Oh, no need to hire anyone, we live upstairs, owner occupied, no absentee landlord here!

Anyone else chime in here?
 
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Old 03-02-17, 05:36 AM
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I flush my water heater a couple of times a year but I doubt I run out much more than 5 gallons.
Since you live upstairs it shouldn't be a big deal to go down there every so often and open up all the taps and let them run for a few minutes. That will put fresh water in all the pipes and add fresh to the water tank.
 
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Old 03-02-17, 06:23 AM
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Yes, that's nothing, the other response was suggesting drain half the tank. Big difference!
I'm mostly concerned about the tank itself.
 
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Old 03-07-17, 09:00 AM
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Personal experience tells me that metal will rust more when exposed to air (which contains a lot more oxygen; the stuff that causes rust) than when exposed/submerged to water.

I would leave the tank full. When the time comes to use it I then drain it / flush it, and then refill it before you heat it back up. You are already flushing it somewhat regularly so if you are due for one then that would be a good time. If not wait until next year, but yeah leave it full.

Unless you live in a place where it gets well below 0c and you will be away for a while. If there is risk of freezing do to heating system stopping (say due to power failure) and you are gone for quite a while with no one around to help you out then I would drain the tank and all pipes in that case.
 
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Old 03-08-17, 04:28 AM
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Ok, I'll buy that. I was thinking of the chemicals & sediment in the water reacting with the tank being a possible concern vs oxygen rusting the tank.
As I stated, this isn't another absentee landlord house, at least half will be occupied as long as I own it.

Amazing, over 150 views and only three came forward.
 
 

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