With the power out, of course the sump pump couldn’t run, & the basement flooded. I assumed from how high it appeared that the standing water got over the gas-powered water heater’s pilot. I turned off the water heater. After bailing out the basement, I restarted the water heater. But wait! The water heater said, if any part has been under water, have a professional look at it.
Yeah, I lit it anyway. Well, after it had been off for almost a day. I hesitated the first time I read that. But once the basement was really bailed out, I did it just the same. Bit of an odd sputter to the hissing pilot at first, but it got quiet quickly. Then I ran a very hot bath.
How much trouble am I in for? Could water still be in the line? Could it travel back & damage my whole natural gas supply? Is there some risk of corrosion, considering if it was submerged (I’m not sure if the pilot really was or not) the pilot was probably under less than a day? Or am I through the worst?
This is one of those one the line things between “what is best practice” and “what can you get away with IRL.”
The main things you’ll need to be concerned about is corrosion risk and the risk of sediment/sludge/crap from the water level deposited on internal electronic or moving parts. Generally speaking, depending upon how electrified your system is, you would have wanted someone to check it out to make sure re-starting it would not cause an electrical short (most simple water heaters, however, aren’t really electrified in any meaningful way.)
And no, water won’t be flowing back up the gas line. The valve was shut whilst it was flooded, else you likely wouldn’t be posting.
Best practice would be to shut it off and call someone to come inspect it for corrosion and sludge and such that could be a problem. Practical real-world says you could probably delay checking it until your annual furnace inspection. Unless of course there are a substantial amount of electronics that were also submerged…
Electronics? This is the one appliance in my basement that works with the power out! There are electronics?
I dunno, but I’ve seen water heaters in the UK which have a programmable thermostat mounted directly on it. Not knowing if you heater was a traditional standard US heater, or one which had more controls and feedback, I made my cautionary fairly broad.
The insulation will retain moisture for a long time and probably cause corrosion on the outside of the tank, possibly shortening its life.
Yes there has to be some control devices somewhere, to control the water temp., start and stop the burner and protect from ‘no ignition/overheat’ failures. Waterheaters can be dangerous if safety controls fail, I’d suggest it’s worth a few bucks to have it inspected. Your homeowners insurance should cover it and maybe even a replacement heater.
Oh, OK then.
Well, I’m going to risk it then.
Just a couple thoughts. A.R.Cane mentions insulation getting wet,a real concern if it is fibreglass,but many new heaters have expansive foam insulation,which is often closed cell.I DO NOT know if that is the case with your heater,or combustion heaters generally.
Since it appears to be back in service,the same thing true of any heater applies,not IF it will leak,but WHEN.You should have leak protection/detection in place,as your recent flood may have advanced the WHEN.
Do gas-fueled water heaters have electronics? Sure they do. Even the simplest unit has a thermocouple which generates a small amount of electricity to satisfy the safety of the main gas valve. The same holds true for newer FVIR heaters with standard venting. If your water heater is sealed combustion power venting style, the majority of the electronics live up top, which doesn’t sound like the OP’s scenario.
I’m going to assume it’s an ordinary standing pilot unit with a thermocouple. In that case, so long as the water level did not submerge any part of the main control (may be marked Unitrol, Robertshaw or Honeywell), it’s safe to relight. If the main control was submerged, it should be replaced. If, by chance, you do have an FVIR unit, it’s important to thoroughly clean the intake filter screen before relighting. Crud left behind by the receding water will partially block it, causing flame wander and safety trip.