Hot Water out of cold water faucets

[harleyguy]

I have a 2013 Coachmen 281 RSLDS with a 6 gallon Atwood water tank.
When I turn on the cold water faucets cold water will come out change to hot water for about 10 seconds and return to cold water. Hot water also comes out of the toilet when flushed. I checked to make sure the water heater winterization valves are set correctly and they are. I also checked the outside and inside showers to make sure the buttons were not set to the off position.
Anyone have any thoughts on a solution to the problem

[cavie]

Originally Posted by harleyguy

I have a 2013 Coachmen 281 RSLDS with a 6 gallon Atwood water tank.
When I turn on the cold water faucets cold water will come out change to hot water for about 10 seconds and return to cold water. Hot water also comes out of the toilet when flushed. I checked to make sure the water heater winterization valves are set correctly and they are. I also checked the outside and inside showers to make sure the buttons were not set to the off position.
Anyone have any thoughts on a solution to the problem

Check your shower valves. They need to be shut off at the valve, not the hose handle. That will cause mixing.

[wmtire]

Originally Posted by harleyguy

I have a 2013 Coachmen 281 RSLDS with a 6 gallon Atwood water tank.
When I turn on the cold water faucets cold water will come out change to hot water for about 10 seconds and return to cold water. Hot water also comes out of the toilet when flushed. I checked to make sure the water heater winterization valves are set correctly and they are. I also checked the outside and inside showers to make sure the buttons were not set to the off position.
Anyone have any thoughts on a solution to the problem

Are you connected to city water, and if so, is the hose laying out in the sun. Sometimes this can happen where when you first turn on the cold water, it's coming from the line inside the RV (thus shaded and/or cold), then starts to draw in water that is sitting in the hose, out in the sun (thus turning hot)...then draws water out of the city systems lines (thus turning cold again).

Summer sun can be a natural water heater.

[cavie]

Originally Posted by wmtire

Are you connected to city water, and if so, is the hose laying out in the sun. Sometimes this can happen where when you first turn on the cold water, it's coming from the line inside the RV (thus cold), then starts to draw in water that is sitting in the hose, out in the sun (thus turning hot)...then draws water out of the city systems lines (thus turning cold again).

That will do it for sure. Hated that when I was a kid drinking out of the hoses.

[TitanMike]

Originally Posted by cavie

That will do it for sure. Hated that when I was a kid drinking out of the hoses.

The hot water from the hose was what we used to wash off all the dirt, dust, or bits of chopped silage from our head and arms. When it turned cold, then we drank. Didn't taste like rubber as much then either.

One other source of hot water in the cold can be backflow from the tank into the inlet cold line. Residential heaters have check valves to prevent the thermal backflow but most RV types don't. They rely on the fact that the cold inlet is on the bottom of the heater and heat rises.

Most common source of the hot water from the cold faucet is from a hose in the sun. If that's a major issue, use a shorter hose so there are no heat absorbing coils and cover the hose to shield it from the sun.

[awellis3]

Originally Posted by harleyguy

Anyone have any thoughts on a solution to the problem

Have you double-checked the bypass valves?

[Delco Bobby]

Originally Posted by harleyguy

I have a 2013 Coachmen 281 RSLDS with a 6 gallon Atwood water tank.
When I turn on the cold water faucets cold water will come out change to hot water for about 10 seconds and return to cold water. Hot water also comes out of the toilet when flushed. I checked to make sure the water heater winterization valves are set correctly and they are. I also checked the outside and inside showers to make sure the buttons were not set to the off position.
Anyone have any thoughts on a solution to the problem

In addition to the other answers just sitting in the sun or a warm day will heat up the cold water lines in my RV. It seems the same as hot but my HW heater was off.

[formerFR]

once we parked for several months at a spot, totally in the sun, during July and August...nice and warm!

I had to run a 100' 3/4" water hose far away to reach a city water connection, and YES, the sun will do wonders and give you FREE hot water! and I mean HOT!!!!! hotter than the water heater!
I eventually grew tired of 'waiting' a minute or more for 'cool' water to finally make it to the coach, so I wrapped the majority of the water hose with 'tube pipe insulation'... solved the problem!

[autoguy40]

I bet Awekkis3 is correct in his diagnosis, since you dewinterized, I would recheck the hotwater bypass valves. I bet the one between hot and cold is not closed off properly

[HerveVR]

harleyguy,

What type of bypass setup do you have? 3 manual valves, 1 3way manual valve with an automatic check valve or other?
An automatic check valve is not that easy to be sure it is operating correctly.

Do you encounter the same issue at night? If so, the sun isn't the culprit.

[Arkansas Traveler]

2x wmtire

[harleyguy]

Thanks for the replies I'll double check the 3 bypass settings and give the tank a good flush and hope that solves the issue