What Does This Error Mean?

Chromagen pressure relief valve leaking is often caused by water pressure in your home exceeding the PRV set point, or the valve is releasing pressure built up from thermal expansion during heating. Occasional dripping during heating is normal — continuous leaking or a stream of hot water indicates the PRV needs replacement.

Affected Models

Chromagen STD series
Chromagen TS series
Chromagen Soltherm
Chromagen Electra Solar
All Chromagen solar hot water units

Common Causes

Water supply pressure too high — exceeding the PRV's rated pressure (usually 700 kPa) causes continuous discharge
Thermal expansion not accommodated — no expansion vessel on a closed system causes pressure spikes during heating
PRV seat worn or corroded — even a small particle can hold the valve open and cause a slow drip
PRV set point too low for the system's normal operating pressure — valve opens before it should
Faulty or failed PRV — the internal spring has weakened and the valve opens prematurely

How to Fix It

Determine if the leaking is normal or a fault.

A small amount of water dripping from the PRV during the hottest part of the day (midday to early afternoon) is normal thermal expansion discharge. Continuous leaking at all hours, a stream of water rather than drips, or dripping when the system is cold indicates a fault. Normal discharge: a few drops to a cup of water per day. Abnormal: anything more.
Check the mains water pressure.

High mains pressure (above 500 kPa) is the most common cause of continuous PRV leaking. Ask your plumber to measure the incoming water pressure with a gauge — most solar water heater installations require a pressure-limiting valve (PLV) set to 500 kPa or below. If no PLV is installed, one should be added before the storage tank.
Check for a thermal expansion vessel.

On a closed plumbing system (one with a non-return valve or backflow preventer), thermal expansion cannot push water back into the mains — all expansion goes into the tank pressure. An expansion vessel absorbs this pressure and reduces PRV discharge. If your system does not have one, ask a plumber to install a Chromagen-compatible expansion vessel.
Test the PRV manually.

Lift the PRV test lever briefly (a few seconds) to confirm it moves freely and reseats without continuing to leak. If the PRV does not reseat after releasing the lever and continues to drip, a particle is stuck in the seat or the valve has failed. A stuck PRV should be replaced — do not attempt to force it closed.
Replace the PRV if it is worn.

PRVs are consumable components — they are designed to be replaced every 5 years or sooner if they start to leak continuously. Ensure the replacement PRV has the same pressure rating (usually 700 kPa for Chromagen systems) and the same pipe size. A licensed plumber should replace the PRV — it involves draining pressure from the hot water system.

When to Call a Professional

A continuously leaking PRV is a safety issue and should be inspected by a licensed plumber. The PRV is designed to protect against dangerous over-pressure — do not block or cap it. Replace a worn PRV promptly.