Hot water on both kitchen faucets

[Oldlawnman]

Hi All,
New to forum!
My current issue is I just bought an 07 keystone cougar 5th wheel. Has rear kitchen and that where water heater is located. The kitchen faucet has two knobs (not a single control handle) and hot water is coming out of both faucets. However the bathroom faucets work properly. Don't understand what the issue could be.

Secondary...
I didn't think the propane pilot would stay ignited if the lighted power switch for the propane water heater was turned off? My previous camper pilot was off when the the heater switch was in off position.

Propane switch is inside unit and the electric part is activated by an outside switch at water heater location. This was also how my previous camper electric/gas heater worked.

Anyone have an explanation for this Phenomenon!

 

[Kirk]

I didn't think the propane pilot would stay ignited if the lighted power switch for the propane water heater was turned off?

The normal operation of the on/off switch for most RV propane water heaters is that when you first turn it on the light will light and stay that way until the heat of the burning propane is sensed and then go out. In many models that light comes on briefly each time the water heater needs heat the lights the propane burner again. The vast majority of RV water heaters have an electronic ignition and do not have a pilot light so nothing is burning when the water is not being heated. As it reaches set temperature the propane goes completely out and none is burned until it calls for heat again.

The kitchen faucet has two knobs (not a single control handle) and hot water is coming out of both faucets.

Do you have an outdoor shower nozzle that may have both faucets open and is turned off at the shower head? A bathroom shower can also cause this. When you do that it allows the hot to mix with the cold water.

 

[John From Detroit]

I'm guesing your water heater bypass is a 3-valve system (and no that' snot the problem)

Let it run for a bit and see if the cold gets cold.
When cold water enters the water heater tank and is heated it expands. This forces some now HOT water back into the inlet line I think you are seeing that at the sink. Should not last long. cup or two at the most.

 

[Oldlawnman]

The normal operation of the on/off switch for most RV propane water heaters is that when you first turn it on the light will light and stay that way until the heat of the burning propane is sensed and then go out. In many models that light comes on briefly each time the water heater needs heat the lights the propane burner again. The vast majority of RV water heaters have an electronic ignition and do not have a pilot light so nothing is burning when the water is not being heated. As it reaches set temperature the propane goes completely out and none is burned until it calls for heat again.

Do you have an outdoor shower nozzle that may have both faucets open and is turned off at the shower head? A bathroom shower can also cause this. When you do that it allows the hot to mix with the cold water.

I've checked the obvious. Outdoor is off and indoor too.

That's how my old one was on propane. You're right no pilot. So mine isn't shutting completely off. Where do I go to find out why? I also smelled a slight propane odor after I turn propane bottles on but didn't after heater switched on and later noticed the small flame and thought it was a pilot but flame is slightly bigger than a pilot.

 

[Oldlawnman]

It's one

I'm guesing your water heater bypass is a 3-valve system (and no that' snot the problem)

Let it run for a bit and see if the cold gets cold.
When cold water enters the water heater tank and is heated it expands. This forces some now HOT water back into the inlet line I think you are seeing that at the sink. Should not last long. cup or two at the most.

It's a one valve system so either you've got hot water or no hot water... unfortunately I've got hot on both kitchen lines but bathroom sink and toilet is normal.

 

[Oldlawnman]

I've checked the obvious. Outdoor is off and indoor too.

That's how my old one was on propane. You're right no pilot. So mine isn't shutting completely off. Where do I go to find out why? I also smelled a slight propane odor after I turn propane bottles on but didn't after heater switched on and later noticed the small flame and thought it was a pilot but flame is slightly bigger than a pilot.

I meant....So flame is coming from the burner because there's no pilot...

 

[John From Detroit]

With a single valve bypass there is a check valve on the OUTLET but generally not on the inlet so as with the 3-valve (no check valve) system hot water can back up into the cold line as the water heats. Try runing like a quart and see if gets cold/room temp if it does or does not we go to the next step (either way) If it does not map out your plumbing with relation to "other things".

 

[Gary RV_Wizard]

Turning off the heater switch causes the heater control board to close the gas valve. If the burner is lit at that time and the valve doesn't close fully, the burner would continue to burn. The flame might be low if the valve is partially closed. I've never heard of that type of failure, but it's conceivable. I guess that would mean the heater gas valve is defective and needs to be repalced.

Hot on both hot & cold kitchen faucets can only happen one of two ways:

• The hot line is physically connected to both hot & cold faucets.
• One of the faucets in the trailer is allowing hot water to cross over to the cold and flow back out through the kitchen cold line. Depending on the faucet design, that could be either an internal failure or a manual crossover via a temperature mixing valve. That sort of problem doesn't necessarily affect all faucets the same.

 

[Kirk]

I think that I'd try turning it off and then check to see if it had any flame at all. If it does then it must be a leaking propane supply valve. I have know of them to fail but I don't recall any that leaked, but it is certainly possible.

 

[NY_Dutch]

It's one

It's a one valve system so either you've got hot water or no hot water... unfortunately I've got hot on both kitchen lines but bathroom sink and toilet is normal.

How long have you let the water run? Our kitchen water lines run close enough to the furnace that they both run quite warm water for about 20 seconds if the furnace has been running recently. It's actually kind of handy for a quick rinse when the water heater hasn't been running.

 

[Oldlawnman]

Thanks. That's not the issue.

 

[Oldlawnman]

I think that I'd try turning it off and then check to see if it had any flame at all. If it does then it must be a leaking propane supply valve. I have know of them to fail but I don't recall any that leaked, but it is certainly possible.

I believe that's the problem. I blew the flame out and was able to and light it with a lighter. I turned off main gas at the tank and let sit for a period of time and I could no light it with the lighter. Guess I'll need to replace the valve.

 

[Oldlawnman]

Turning off the heater switch causes the heater control board to close the gas valve. If the burner is lit at that time and the valve doesn't close fully, the burner would continue to burn. The flame might be low if the valve is partially closed. I've never heard of that type of failure, but it's conceivable. I guess that would mean the heater gas valve is defective and needs to be repalced.

Hot on both hot & cold kitchen faucets can only happen one of two ways:

• The hot line is physically connected to both hot & cold faucets.
• One of the faucets in the trailer is allowing hot water to cross over to the cold and flow back out through the kitchen cold line. Depending on the faucet design, that could be either an internal failure or a manual crossover via a temperature mixing valve. That sort of problem doesn't necessarily affect all faucets the same.

Oddly I think the water being hot on the cold side was due to there being a constant small flame in the chamber. Also the water was scolding hot. Once I turned gas off at propane bottle the flame finally went out. I let water completely cool in tank and then reheated the water on electric mode. Hot water side was hot and hold water side remains cold. I'll be replacing that propane valve. Thanks

 

[Ray-IN]

Thank you! It's gratifying to hear the results of a posted problem.