problem with water heater thermostat?

Hello all,

I have a 1 year old Bradford-White gas water heater, works great when all is well. On a couple occasions it seems as if the thermostat does not turn it on when it should, and I have a lukewarm soon to be cold shower. Most recently this happened yesterday, I had turned off the main water, and the water tank inlet valve, to work on some plumbing (rough in a new bathroom). After having water shut off for about 5 hours, I repressured everything and went on my way. Last night the water was cold, I checked and the tank was firing, then this morning it was barely warm. I tweaked the thermostat back and forth and set it slightly hotter just to see if maybe it hit a deadspot or something, I will see if that helped later tonight.

So, does this sound like I need a new T-stat? Is it a straightforward part for a DIY guy to replace?

Thanks for the help.


Greg

heater

That is one possible cause, but I would not replace the thermostat until ALL other possibilities are discounted. Otherwise you may spend time and money on a replacement and have the same problem afterwards.

think I solved it

I had installed a rough-in valve for a Delta shower, and in spite of the stops I think it was flowing from hot to cold, or vice versa. Just ran home and sweated in a couple proper ball valves, I'm hoping that cures it.

You wouldn't be the first person who ended up with a hot/cold crossover from the Delta Universal rough in... I'd say in the forums I'm on, its probably 50% of the crossover cases.

I do not have stops before my shower/bath faucet. Is it worth soldering in ball valves on the hot and cold lines?

Is this conventional?

Two schools of thought: they are handy IF you need them during rough-in and want to keep the main water on and they are handy for doing maintenance much later when it does finally need replacement. Problem is, they may not work many years down the road, so it may not be worth the effort.

Some valves offer them as an option from the factory.

valves

That is what happens when we do not have all the information about what you were doing. You didn't mention that you were doing a shower valve replacement. Valves are handy, except a Delta valve can be serviced without removing the trim plate, so even if you had integral stops the plumber would either not know they were there in the first place or would not use them because they would be more trouble than they were worth.

Do you have a recirculating pump? Water generally does not cross from hot over to cold, unless you have a pumped system. Otherwise, you get crossover from cold to hot, but that just cools down the pipe, and does not really send cold water into the tank.

I do have a recirc pump, it is the type with the return line, not the type that dumps hot into the cold pipe.

I think the cold shower was just the water taking the path of least resistance, the Delta rough in is directly below the upstairs shower and thus a short path from the crossover to the shower. All is well now.