Installing New Pressure Reducing Valve

Hello everyone... my pressure reducing valve has failed and my home’s water pressure is approximately 100PSI. My initial plan was to simply replace the existing valve until I saw where it was installed.

The existing valve is installed outside of the house in an access box that is below ground level by a few inches. I assume this was intentional because the area freezes during cold winters and having the unit below ground reduces freezing. However, because the valve sits below ground, it often sits buried in dirt, water, and mud. As such, I think it would only continue to fail prematurely if I replaced it in its current location.

Question: would it be reasonable to keep the failed unit in place (allowing it to sit buried under mud and dirt) and just install a new reducer valve inside the garage near the water heater? I think this would not only prevent the unit from freezing, but it would keep it free of dirt and mud and allow easy access year round. Unless anyone can add anything, I see the only downside being the fact that there would be some pipe (approx 20 feet) between the old unit and the new unit that would be exposed to the higher pressure.

Thoughts?

Thanks!

All the piping is rated and constructed for a max psi of 150. There is no issue. It is the components inside the house...faucets, toilets, etc. that don't want to see over 80.

I would do what you suggest. Most new houses around here have the main shut off and the PRV inside the garage, for convenience even though it doesn't freeze. Older houses, going back to the 60's, had them outside on the front of the building, and before that, they were underground in the meter box.

there are valves that are built to be out side in your conditions "watts"with z3 suffix use all brass body's and stainless steel hardware

worsnup said:

there are vales that are built to be out side in your condions "watts"with z3 suffix use all brass bodys and stainless steel hardware

Click to expand...

Thanks. Yeah, I imagine there are products that could withstand the weather and abuse of being buried under water and dirt. However, I imagine having a PRV located upstream from the water heater inside the garage with a downstream inline pressure gauge would be incredibly useful and accessible.

At this point, I am hoping folks can either bless that idea or tell me why that would be a bad choice.

Inside with a pressure gauge downstream is an excellent way to install a PRV. Install two isolation valves (ball valves) and use two unions, one on either side of the PRV and you have made it easy to remove the PRV for repairs or replacement in the future. If you also plumb in a bypass you are set for life.

And do not forget the thermal expansion tank on the wtr/htr at the same time ! !

The problem might be if being buried eventually rusts the adjusting spring. If that happens the pressure, and flow, will drop to ZERO, and you will then have to remove the bad PRV. Better to do it now.

My plan to add a new PRV upstream from the water heater may not work since it looks like the junction where the water feeds the rest of the house splits off somewhere where I can't see it. If I add the PRV to the pipe immediately before the water heater, it will only reduce the pressure at the water heater and downstream from there. I don't know where the upstream split would be that feeds cold water to the rest of the house.

What path does the water supply line typically take from the reducing valve? Does it usually split off immediately and send one cold water line to the heater and one to the internal cold water plumbing, or is the split usually behind a wall nearby the water heater? I am trying to find the last place I can add the PRV before the water gets sent to all of the plumbing and appliances... hopefully somewhere that I can reach.

To be useful, the PRV should be installed near where it enters the house. You may want to have the branch that feeds the hose bibs come off before the PRV. There is little advantage to having it just on one side. Not sure if it is designed for or would work long on the hot water side. Once you install it, as part of the installation, you'll need to add an expansion tank feeding the cold side of the WH, or you'll end up with the T&P valve dripping after heating a bunch of water.

THere is NO TYPICAL installation. It is taken off wherever the installing plumber decided to do it.