During bath remodel I lost hot water. Help!

Ok. I'm having my master bath remodeled. After they took the old tub out they also removed the old valve and put in a new one higher up for a shower only. I'm replacing the tub with a shower. This was on Wednesday. Wednesday night I noticed a decrease in hot water. It was warm only. On Thursday morning even less hot water. My wife showered with only the hot on and she said it was luke warm. So when they remodeler gets here I ask if anything he did could effect the hot water. He said no and said maybe an element in the water heater was bad. I drained the heater tank and removed the elements. They looked bad and the tank was full of sediment so I decided to replace the heater. I don't know how old the other one was. I've been in the house 6 years. Installed new water heater yesterday. Water is still only warm even though I have it set to 150. When I flush a toilet with the hot water running it then gets really hot. SO the hot and cold must be mixing somehow. Could this be the result of the new shower valve install? What if he has the hot hooked to the cold and vice/versa? Would this allow the hot and cold water to mix? Please help!

Thanks,
rob

Depending on the brand some have an adjustment on the handle that may just need to be changed to allow more HW to flow through the valve.

The new valve should have had a pressure or temp. balance (or both) on it to prevent what is happening when the toilet is flushed.

Do you know the brand of valve?

Could be a bad new valve, unlikely but possible.

The new valve is a Delta. The bathroom in not completed yet. I'm talking about the other bathroom. When I turn on the hot water at the sink it comes out as warm. When I flush the toilet it gets really hot when the toilet is filling then gets warm again. The shower, sink and toilet in the remodel bath are not completely hooked up yet. Just the new valve is in place and the walls have been roughed in.

Sounds like you may have a cross connection mixing the hot and cold. Hard to tell from here.

water

Well, if you were in this area and had a concrete slab floor, your symptoms would almost always mean that you had a hot water leak under the floor. I am not sure if it applies to your house, but in any case you need a plumber to check it. Many people around here, even some inexperienced plumbers, also replace their water heaters when it happens only to find they still have the original problem.

The house is off-grade construction, so it's not on a slab. Maybe there is a leak. I just find it wierd that it started after they installed the new shower valve. The guy should be here soon so I will have him check the valve and go from there.

Your plumber might have hooked up the Hot and Cold to the Shower and Tub connections on the faucet. He then plugged the hot (or cold) thinking it was for the tub spout. Wouldn't fail to work, but would fail to mix.

Jason

Sounds like Cass is correct...

I would say that the shower arm stub-out is capped and the shower valve is open - thereby creating a cross connection. Your remodel is surely done by now, but there you have it!