My pressure reducing valve (or restricting valve) was looked at by three master plumbers and they all said I need a new one. My water pressure has been low for weeks. It measures about 100 psi at the outside hose bibs, but it is very low inside and suddenly reduces after you turn on the facets inside. The shower is ok. My automatic sprinkler system is not able to work now due to low pressure. A relative of mine thinks we can just add a handle (as one is missing) on the valve and adjust the pressure ourselves. The repair of the valve is around $500-600! I am told in Texas that we have to have a permit and inspection to repair this valve. Also I was told by the last plumber that came out, that I have to install a expansion tank on my new hot water heater according to code. I'm not sure if that is a city code or federal. Please respond as to information you may have on this problem. The expansion tank is required I'm told when you have a pressure reducing valve for safety, is this true?
The cost you quoted seems a bit high to me. Mine didn't cost anywhere near that amount in East Texas. A pressure reducing valve acts like a check valve when there is no flow. That is it closes as the pressure rises when you are not using any water. In this condition, the hot water heater can raise the pressure even higher since there is no place for the expanding water to go. That is the reason for the expansion tank. Without the expansion tank the pressure relief valve on the hot water heater can relieve unnecessarily or weep a bit.
