At Ask Me Help Desk you can ask questions in any topic and have them
answered for free by our experts. To ask questions or participate in
answering them you must register for a free account. By registering you
will be able to:
Get free answers from experts in any of our 300+
topics.
I added a shower to my place and now I got hot water coming out of my cold taps for the first 15 seconds or so. All I changed from before was to add 2 tees into the line, one from the hot and one from the cold water lines. What's happening? thx.
do you have a hot water recirc pump on your system? If you do, make sure you didnt tie into the recirc line instead of the hot water feed line. Also, how close to the water heater are the tees you installed?
This might explain your problem. When the water in the water heater is not used for a while the heated water in the tank will expand and go backwards into the cold line, also the law of phisics applies here that hot rises and cold falls, therefore again you have hot water rising into the hot water line. Since your tee's are so close to the water heater some of the hot is backed up in the cold line that furnishes your new tee and until the hot is flushed out you will get the small amount of hot water out of the cold line.
If you have some one to help you check this you check the heat in the cold water inlet at the heater and see if it is real warm and when someone turns on the cold in the shower it gets cool.
If this is the case, nothing to worry about really. If you just cant stand it. you can install a either a heat trap, or a heat trap nipple off the top of the cold inlet side of water heater. If you do go the heat trap route, make sure that the trap is between the water heater and any other colds that come off the cold water heater supply
I installed a check valve at the hot water heater and that fixed the problem totally. Thx to everyone for their info.
Putting a check valve in the incoming line to a water heater is not a good idea. The reason being that in a case where the gas to the burner fails to cut off you do not have a one hundered percent safty that steam will not build up in your heater and create a bomb.
And yes I know that you have a pop-off valve for such emergencies, and you have a cut off build into the thermostat to protect against this sort of problem. But none of them are one hundred percent postive protection.
I can see LetmetellU s point about the check on the cold water supply but if there's already a backflow preventer install the system's closed already. I didn't think of that in my reply. Thinking it over I think you're absolutely correct Lee.
A check valve and expansion tank it is. Cheers, Tom
I think you will be just fine with the check valve, but you will need to add an exansion tank on the water heater side of check valve. Many areas require a check valve on home incoming water anyways, so installing one on the cold supply of water heater makes no difference.(except to cure your problem of hot water in cold line) The reason for the expansion tank is so that when the water in the water heater heats up and expands, it wont blow off your temp/ pressure relief valve. I personally would have like to see you use the heat trap nipples, but a check valve will work just fine to.. Just make sure to get that expansion tank install asap. With a check valve installed right before water heater, it wouldnt hurt to manually pop off your pressure relief vavle now and again just to make sure it is not stuck. 'The only problem with this is,,, once you pop them off manually, they tend to drip, so i would have a spare one on hand just in case you cant get it to shut down completely.
Tom, just wondering how an expansion tank will take the place of a check valve. I dont think an expansion tank will keep the heat from radiating up the cold side. But i have been wrong before, and i promise i will be wrong again(most likely many times..)
Linear Mode
