Should the pressure relief valve on my natural gas hot water heater leak out of the pressure relief valve everytime the burner comes on to heat the water?
It has been doing this for several months and my builder said his plumber told him it is normal.

Also the temperature just dropped yesterday without changing the setting on the water
heater. You used to have the turn the heat down in the shower or bath but now
you can leave it full hot and it will not run you out. What has happened here?

The heat setting on the hot water heater is midrange between warm and hot on the preset
white mark.

KeepItSimpleStupid

WIth a new house, there may be debris in the pipes. That may explain the water temperature problem. The debris cleared.

Ground water temperature is about the same year round, but their is some variation, Thus you can expect longer showers in the summer, for this reason and your skin is warmer.

The pressure relief valve should not leak. If there is a check valve in the water system, then an expansion tank on the cold water side has to be added. If your pressure is too high, the valve may leak. Normal is about 55 PSI.

KeepItSimpleStupid

From PM: Use the forum for follow ups

I'm basing my answer on the shower and not the other fixtures because that's the only information I have. I also don't know the type of faucet you have in the shower.

Suppose I turned down the cold water to the shower because a rock could no get past a cold water valve. You would have more hot water because there is less cold to mix. Eventually there may be erosion that allows the particle to pass.

I would suggest removing the aerators on the faucets and turn them on for a while. Also remove some water from the water heater. You should do it monthly. Drain until the water is clear.

You didn't mention if there was a change in the amount of water.

There's lots of other info that could help and we can either answer based on info given or ask for information we don't have.

Checking water pressure:

Buy a guage that has a hose bib attached to it and use an outside faucet such as: Pressure gauge- adapts to outside faucet- easily measure home water pressure. reverse osmosis

The check valve in the water line will do it everytime. It's basically a back flow preventer for the utility. Check valves and pressure regulators are not common.

dirtbikedad

Temperature change is at every source in the house, even the kitchen sink with only the hot water turned on. House is plumbed with a new type of plastic tubing, red for hot, blue for cold, all coming off a kind of distribution box where you can turn off any room from that point either hot side or cold side individually.

Does this information help?

hkstroud

Your water heater has a defective temperature sensoring unit. The P&T valve should not be releasing each time the burner comes on . Builders will say anything. The sensor may now be functioning properly but it would be very unusual for something to fix itself. As the heater is functioning now your P&T valve is not releasing is it? The builder is very unlikely to do anything, especially now that things are functioning more normally. Suggest that you contact the manufaturer to see if they will do anything under the warenty at this time.

speedball1

Well somebody's blowing smoke up someones skirt. It certainly isn't "normal" for a T&P valve to leak. Who's the liar? My guess is the builder because a plumber would never tell you that. One of two things, a faulty T&P valve or you have a sprinkler system with a check valve or a backflow preventer installed out near the water meter. My bet's on the latter. If that's the case you will need to install a expansion tank,(see image) in the cold water supply of the water heater,(see image). First you have to understand a expansion tanks function. When new codes forced us to install check valves and backflow preventers on water service lines thyat made your water system a closed system. That meant that when the heated water expended it could no longer expand back along the water service line and would build up pressure in the syatem. this would kick off the T & P ,(Temperature and Pressure Relief) valve aqnd the valve would discharge hot water out the relief line. To prevent this we installed a Expansion,(Air) tank on the heaters cold water supply line for some place the water to expand to. you check a expansion tank exactly the same way you check a bladder tank on a pump. You tap the tank walls, if you hear a "clang" you have air inside and the T&P valve's protected. If you hear a "clunk" that indicates the tank's loaded with water and must be removed and drained to recharge it. Good luck, Tom

KeepItSimpleStupid

That's what I said, but Speedball said it better. That distribution system could have a check valve in it.