Pressure Relief Valves for Water Well Systems
Shop Pressure Relief Valves →Stop high pressure before it ruptures your tank, splits fittings, or causes flooding.
Merrill cold water pressure relief valves for well systems open automatically when pressure gets too high, protecting your pump, tank, and plumbing. Match the size and pressure rating to your system and install it by your pressure tank for simple over-pressure protection.
Pressure Relief
Valve Guide
No-Lead Brass
- Cold water systems
- Most residential wells
- Most common
Stainless Steel
- Corrosion resistant
- Harsh water conditions
- Long-term durability
Heavy-Duty
No-Lead
- Custom Settings
- High pressure systems
- High flow capacity
PVC
- PVC tank tees
- Lightweight
- Cold water only
well systems
systems
Settings Available
Match valve size to your tank tee or piping size.
Pressure Relief Valve Reviews
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Common Questions
Where does the pressure relief valve go?
Thread it into the tapping next to your well pressure tank—usually right on the well tee or manifold. It threads into a standard 1/2" or 3/4" port. Just make sure the discharge points where water can’t hit anything electrical.
What size and PSI do I need?
Most home well systems run a 1/2" or 3/4" cold water pressure relief valve at 75 PSI or 100 PSI or VFP. Match the size to your tank tee or pipe. Go with 75 PSI for normal setups, 100 PSI if your system runs higher on pressure.
How do I know if my pressure relief valve is bad?
It’ll leak, drip, stick open, or never open when pressure spikes. If your 75/100 PSI cold water safety valve won’t stop weeping shut off power, swap it out before it floods the area.
How hard is it to replace?
Replacing a 3/4" or 1/2" pressure relief valve is usually straightforward: shut off power, drain the system, unscrew the old valve, and thread in the new Merrill valve with proper thread sealant.
Which Merrill pressure relief valve should I use?
For most residential cold water well systems, use a Merrill 3/4" or 1/2" pressure relief valve set at 75 PSI or 100 PSI. Use 75 PSI for standard systems and 100 PSI for higher-pressure setups.
Why is my pressure relief valve leaking?
Common causes include high system pressure, debris inside valve, or a waterlogged pressure tank. If the valve keeps weeping or will not reseal, replace it.
Can I adjust the pressure setting on my Merrill valve?
They are field adjustable, but adjustment voids the warranty and is not recommended. Leave the factory setting at 75 PSI or 100 PSI.
Can I use a Merrill pressure relief valve on my water heater?
No. Merrill pressure relief valves are for cold water well systems. Water heaters require a temperature and pressure relief valve rated for hot water.
Do I need a pressure relief valve if I have a pressure switch?
Yes. Pressure switches and tanks can fail. A 3/4" or 1/2" pressure relief valve acts as a backup safety device if system pressure gets too high.
How often should I test or replace my well pressure relief valve?
Check yearly for leaks or corrosion. Replace it any time it drips, will not reseat, or every 10 years as routine maintenance.
Stop High Pressure Before It Causes Damage
Shop Pressure Relief Valves →Merrill cold water pressure relief valves open automatically when pressure gets too high, helping protect your pump, pressure tank, fittings, and plumbing from over-pressure damage.