Is PRV bad....

[cc66]

Hello,

First, thank you in advance for your help. Six foot downstream from my homes PRV and shut off valve is an inline pressure gauge that reads 103 psi with no faucets open anywhere in my home. If I turn the PRV adjustment screw counterclockwise until is stops and then open a faucet in my home. The pressure drops to around 10 psi. Once I close the faucet the pressure goes right back to 103 psi with the PRV adjustment still in the position that I set it at the beginning. So, is the PRV bad? if you don't believe it is bad. what is the best way to adjust the PRV to set the pressure to 60 psi?

 

[Gary Swart]

When you screw the PRV down, you are essentially shutting the house water off...must have a slight leak to register 10 psi. Adjust the PRV with an eye on the pressure gauge. When it read 60, you're done. Next question is, do you have a thermal expansion tank between the PRV and the water heater? You should have and the expansion tank's air pressure should be set at the same pressure as your PRV. I don't think your present PRV is malfunctioning, it just needs adjusting, but PRV's are a mechanical device therefore they can fail. At that time, it's usually best to install a new unit rather than trying to repair the old one.

 

[Sponsor]

 

[cc66]

Gary,

I'm replacing the Rheem gas water heater in my home with a Rheem Marathon electric water heater. My present water heater does not have an expansion tank, but I'm installing one with the new water heater. Even if I move the PRV adjustment clockwise or counter clockwise while watching the inline pressure gauge it does not change.

 

[Gary Swart]

Then I'd say it's time for a new PRV. Why are you replacing a gas heater with electric? Gas is far better for heat water, it's cheaper and faster. Your business, but makes me wonder.

 

[hj]

The pressure with a faucet running is the "set" pressure for the valve and it should NOT vary by more than a couple of pounds whether the faucets are on or off. The increase in pressure is a sign that the valve has failed. Replace it.

 

[cc66]

Then I'd say it's time for a new PRV. Why are you replacing a gas heater with electric? Gas is far better for heat water, it's cheaper and faster. Your business, but makes me wonder.

Gary,
My gas water heater is 13 years old been having issues with it for last few years. Natural gas cost my 0.95 to 1.35 per therm. Electric cost me 0.14 to 0.16 per KWh, so I decided to go back with electric. Thank for your help.

 

[Jadnashua]

So, a therm of NG produces about 102,000 BTU, or just under 30KWh of electrical power. At $0.14/KWh, your energy cost for the equivalent NG energy is: $4.20. Even if the NG WH was only 50% efficient (most are quite a bit better than that AND reheat the water faster), you're paying over twice the amount to convert...doesn't sound like a good deal to me!