Water heater pressure relief dripping

[lindy46]

Just to clarify, I did install a new T&P valve. I'm using the fresh water tank and pump. It still leaks a little as water is heating up, but seems to stop leaking after its left on for a while. It's not enough water to overflow the pan at the bottom of the heater. I guess I won't worry about it. If it was a constant leak running down the side of the camper, I'd be more concerned.

[lindy46]

By the way, the fresh water inlet (where you connect the hose) does leak when using the internal water tank and pump. To remedy this, I install a plug when using the pump. That was easier than replacing the faulty inlet assembly. I don't know if this is related to the dripping T&P valve. Maybe if I let the fresh water inlet drip, the T&P valve wouldn't Drip?

[bobbecky]

There is probably a leaky seal in the water inlet, and if it leaks when using the onboard water pump, the pump will constantly cycle because of the leak. You also must remember that the T&P valve opens at 150 psi, so your entire water plumbing system is pressurized at that pressure when the water heat gets hot. I laugh every time there is discussion about what water pressure is appropriate in the RV, because the PEX plumbing and connectors are at least rated to handle the pressure. We full time, and I gave up worrying about the water dribble from the T&P valve a long time ago.

[JRTJH]

^^^ Some people look at the water system as being "safe to 160PSI because it's built with PEX tubing that's rated at that operating pressure... But they fail to also consider that all those plastic elbows and tees are rated at 110PSI and when they are crimped and subjected to "earthquake level vibrations" when bouncing down the highway, that PEX tubing pressure rating isn't the limiting factor any longer...

I prefer to keep my operating pressure at 40PSI and always, ALWAYS turn the water off at the supply source or at the onboard water pump if we're going to be anywhere other than "at the campsite. A sudden leak from a split plastic elbow or a "slipped crimp ring" can flood a trailer in just a few minutes without regard to whether you're 3 sites away at the pool or 30 miles away getting more charcoal for steaks tonight.....

[GlasNav]

The use of a pressure regulator, not the cheap ones but something along the lines of an adjustable Renator alleviates hydro hammering when in a campsite with 100 PSI supply. If you flush your toilet and it hammers to the point of shaking the entire trailer when releasing your foot, the water pressure is way too high!

[lindy46]

Yes, I keep the pressure regulator set at 45psi on the incoming line so there is no way the pressure is 150psi. We always turn the water off when we're away from the camper. On an older camper, we had a line blow when we were sleeping - woke up to a flooded camper! We don't turn it off at night, though we probably should. If using the pump, I do shut that off at night. I think I'll start turning the water heater off and external water supply off at night. We can always turn the pump on when we use the facilities in the middle of the night. Oh, the things you learn over the years. Camping is a lot of work!

[bobbecky]

Originally Posted by lindy46

Yes, I keep the pressure regulator set at 45psi on the incoming line so there is no way the pressure is 150psi. We always turn the water off when we're away from the camper. On an older camper, we had a line blow when we were sleeping - woke up to a flooded camper! We don't turn it off at night, though we probably should. If using the pump, I do shut that off at night. I think I'll start turning the water heater off and external water supply off at night. We can always turn the pump on when we use the facilities in the middle of the night. Oh, the things you learn over the years. Camping is a lot of work!

Unless you do turn off the water heater, the water plumbing being a closed system with the one way check valve on the city water hose connection will allow the pressure to reach the pressure relief setting of the T&P valve, which is 150 psi, regardless of what your water pressure regulator is set at. Turning off the water heater will work, but the plumbing can still see the high pressure when you are using the water heater.