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bledsoeIN
Hot water backing up into cold side of hot water tank

I'm having an issue with hot water backing up into the supply side of the hot water heater. I have installed heat traps and they have not helped. I can put my hand on the cold water side, up to several feet, and still feel hot water.
What could be causing this?

canuk
Re: Hot water backing up into cold side of hot water tank

Hmmm ... curious ... I'm wondering if you were to turn down the heat on the water tank if the problem goes away or is not as sever.
It could it be a faulty pressure relief valve ?

Just a guess.:)

i.m.plummin
Re: Hot water backing up into cold side of hot water tank

I need more info. You Installed heat traps. Mechanical gadget or an piped trap. Do you have a hot water return line?If so where does return to? What temp is your water heater set at for temperature? Where is it located?

bledsoeIN
Re: Hot water backing up into cold side of hot water tank

The hot water heater is less than one year old and I try to keep it's temperture as low as I can.
There is not a return hot water line.
The heat traps are two threaded pipes that are 4 inches long and they have a flap in them to reduce siphoning of water when water is turned on at other locations.
One of my thoughts on it, is that there my be a small leak outside that lets the pressure back off, letting the hot water back out of the hot water heater.

i.m.plummin
Re: Hot water backing up into cold side of hot water tank

Not doubting a leak but I dont think that would cause the problem. Heat rises and telegraphs. I would try a check valve an a physical heat trap and (if space permits it) an expansion tank preferably at the top of the trap. You construct it with 12" min. up 12" over and 12" into the water heater. sweat a tee on the first rise and a female fitting adapter in the top of it and the rest should make sense. Thread the XP tank into the female adapter( make sure you get the right size. Construct the same minus the tee on the hot side. Drink some coffee and stick you chest out cause your doin some plummin.:) Don't set your water heater too low as legeionella can grow in the tank. I know energy and all that. Energy Dept vs Health Dept the battle rages.;)

canuk
Re: Hot water backing up into cold side of hot water tank

i.m.plummin ... question ... if the pressure relief valve was not working properly could this cause the hot water to back up into the cold water supply ?

JacktheShack
Re: Hot water backing up into cold side of hot water tank

Both Canuk and Plummin provide good insight & suggestions.

Also check site below:

At the site, click onto "solve a problem", then scroll down & click onto "tanklets", then onto "cross connections", "heat trap issues", "correct temperature" and "dip tube".

http://www.waterheaterrescue.com

JLMCDANIEL
Re: Hot water backing up into cold side of hot water tank

Although your water heater is only a year old you may have a broken or missing dip tube in the water heater.
Jack

i.m.plummin
Re: Hot water backing up into cold side of hot water tank

Not doubting the broken dip tube or anything fellas BUUUUT the thermal transmission of the watter mass itself can still telegrapgh through the lines.

Furthermore blesoeIN's problem is REAL common and honestly aside from radiation heat loss (efficiency) its not worth worrying about unless its back feeding to some fixture or fixtures. And the flow check would stop that.

If the dip tube is broken or missing then the problem would be diminished hot water volume i.e. Customer says, "We start out with good hot water but it turns tepid and runs out real fast."

bledsoeIN says his cold water feed is hot. If the T&P is malfunctioning then bledsoeIN would be getting scalded or have waterlines popping apart. I say this because the function of the T&P is to protect the system and the tank from (and this is specific to residential water heaters) temperatures over 210 degrees Farenheit and pressures over 150 psi.

I'm going strictly on past experience and some mechanical knowledge. I am not an engineer ............yet;)

JLMCDANIEL
Re: Hot water backing up into cold side of hot water tank

The reason I mentioned the dip tube is because it occured to me that he may have been checking the HW heater for some other reason and discovered the hot supply line.
Jack

bledsoeIN
Re: Hot water backing up into cold side of hot water tank

Thank you all for your suggestions.

I have also thought of installing the XP tank but I did not fully understand their funciton. I also thought of installing the check valve but wasn't for sure if it would cause excess pressure on the tank. The tank does have the pressure valve on top for safety.

As for the cold water drip tube, I have removed and inspected it. I found no cracks or holes that should not have been there.

A cousin suggested to make a loop in the cold water line right before it goes into the take. He called to a dog loop. He said sometimes the hot water will not get past the loop but it doesn't explain the problem I am haveing.

Thanks

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