PDA

View Full Version : Hot water heater draining cold water?


chipster51
May 2, 2011, 11:30 AM
I have tried to drain my HWH. I cut off the breaker, connected hose to the drain, and cut off supply. I opened a hot water faucet and then tried to drain the tank. Nothing. OK maybe sediment blockage. I then turned on the cold water supply to HWH and the drain hose is draining cold water while the faucet inside still is supplying hot water. I am totally confused. When I cut off the cold water supply to the heater all flow stops. Hose and faucet. I'm sure there is an easy answer here somewhere. That's why I came to you folks. Thanks

ma0641
May 2, 2011, 01:28 PM
The dip tube is introducing cold water to the bottom of the heater like it should. Turn off the CW supply to the heater. Go to the highest bathroom and open the tub HW faucet. Now go back and open the heater tap. Water will come out now.

ballengerb1
May 2, 2011, 01:45 PM
I assume you actually want to flush your water heater, right? You have created a trap with no supply you can't drain. Open the supply and the drain at the same time, this is how you flush a heater. Draining one is somewhat worthless, you have to flush them out to do any good.

chipster51
May 2, 2011, 02:47 PM
Thanks guys. I did flush it out with supply on.I could not seem to get anything out of the drain with the supply off even when opening a hot water tap. Not sure if I got all the sediment out. It did quit draining after a while until I cut the drain tap on and off a few times. I am trying to fix a problem with the kitchen tap. After about 30 seconds with hot water running I hear a hammer and the hot water flow just keeps reducing. I appreciate the info on the dip tube. That makes sense now. I am waiting for it to heat back up now. Somehow I doubt if I solved the problem.

massplumber2008
May 2, 2011, 03:04 PM
Hi Chipster...

If you are getting a hammering sound then it is possible that a washer has become loose and is "fluttering" when you get the water flowing strongly.

Here, I would recommend that you work your way backwards. Start by disassembling the kitchen faucet (hot side only if possible) and look at the hot washer or stem assembly and see if anything is loose there. If not, reassemble and go underneath the sink and disconnect the hot hose from the faucet. Now, direct that hot supply hose into a bucket and turn the hot water on full flow. If you get that fluttering then you will need to shut off the cold water supply into the HWH and then disassemble the hot shutoff... inspect the washer, right? If that fails to show you anything then it is possible that the hot water nipple at the HWH is a heat trap nipple and needs to be removed and replaced with a new dielectric nipple... however, if this was the case you should also be seeing the issue with other faucets, OK?

Start disassembling and see what you find... post back with results!

Mark