Tools You'll Need
Step-by-Step
Get a pressure gauge
Available at any hardware store for $10–15. It screws onto a standard outdoor spigot or washing machine outlet.
Find an outdoor spigot
Use an outdoor faucet or a washing machine connection. Don't use a sink — the aerator restricts flow and gives a false low reading.
Make sure no water is running
Turn off all fixtures, appliances, and irrigation. Any water running will give a false low reading.
Screw on the gauge and open the faucet
Hand-tighten the gauge onto the spigot. Open the faucet fully. The gauge will show your static water pressure in PSI.
Read the pressure
Many homes operate comfortably around 40–60 PSI. Pressure above 80 PSI is generally too high for residential plumbing and should be evaluated; the cause may involve a missing, misadjusted, or failing pressure-reducing valve, or another system condition.
Check with water running
Open a faucet inside the house while watching the gauge. Pressure should drop slightly. A big drop may indicate a supply issue or a clogged PRV screen.
WHEN TO STOP
- If pressure is above 80 PSI, avoid adjusting unfamiliar pressure-control equipment yourself and have the system evaluated.
- If pressure is below 40 PSI and you have a PRV, the PRV may need adjustment or replacement.
WHEN TO CALL A PROFESSIONAL
- Pressure is above 80 PSI — the pressure-control setup should be evaluated to determine whether a PRV is missing, misadjusted, or failing.
- Pressure is below 40 PSI throughout the house and you can't identify the cause.
- Pressure drops dramatically when one fixture is used.