Water Heater Relief Valve Pouring Water
It's not just the pressure, it's the water temp. And somthing is very wrong.
Everyone,
I just found this post about a water heater relief valve leaking on RV Tips.
Any idea why my water heater was pouring water from here? The water also does tend to get scalding hot so I only run it in very short bursts. Used it earlier today no issues, tried to turn it on and noticed it was just pouring. Turned off water for now.
What’s happening?
It’s pretty obvious that your water heater thermostat is stuck in the ON position and constantly heating the water up to the boiling point. The T&P (Temperature and Pressure) Relief Valve is doing its job by sensing the over-temp condition and relieving the excess pressure before it can explode.
How Temperature and Pressure (T&P) Relief Valves Work
The last line of defense for pressurized equipment, Temperature and pressure (T&P) relief valves are critical safety devices that protect equipment from excess pressure and, ultimately, catastrophic failure.
T&P valves used on residential water heaters are typically designed and manufactured to relieve pressure at 150 psi and temperature at 210 degrees F. ASME, ANSI and CSA (AGA) approved relief valves protect the water heater from excess pressures and temperatures by discharging water.
What to fix
You need to replace the water heater thermostat so the water is only heated to a maximum of 120 to 140 degrees. And I’ve found that once a relief valve opens up from over-temperature it will always leak. So that T&P relief valve should be replaced as well. And while you’re at it, check to see if you have an anode rod and replace it.
Let’s play safe out there… Mike
This past winter we stayed in one place for 4 months, the longest without moving so far in 10 years. About 3 months into our stay our relief valve opened spewing scalding hot water everywhere. First thought was the heating element was stuck on however I verified it was not, so I my thoughts went to a defective relief valve and I replaced it. A vacationing RV tech was staying in the resort that we made friends with and he described that the water heater is built to have an air space at the top of the tank for expansion. He also said that when staying that long the water heater can loose this air space and to just turn off the water and carefully open the relief to reestablish the air pocket from time to time. So was it a relief valve failure, I don’t know, however no issues since!
Mike, those values tend to stick with dirt in them. Just want to remind people to flush them when water is cool.