Chromagen Overheating Warning — What to Do

What Does This Error Mean?

An overheating warning means the tank water has exceeded the safe maximum (usually 75–80°C). The system shuts down heating as a safety measure. Do not use hot water immediately — it can scald. Let the tank cool to a safe temperature first.

Affected Models

Chromagen CR Series
Chromagen Optima
Chromagen Crown
Chromagen Prisma

Common Causes

Extended sunny weather with no hot water usage
Boost element left on overnight combined with full solar gain
Tempering valve failed — excessively hot water reaching taps
Pressure relief valve releasing water due to thermal expansion
Thermostat set too high on the backup element

How to Fix It

Wait until the tank temperature drops before using hot water.

Water above 60°C causes scalding burns in seconds. Wait until the controller shows the tank is below 60°C before using the hot tap.
Check whether the boost timer is on.

If the electric boost ran overnight AND the panels collected full sun all day, overheating is inevitable. Disable the boost timer in summer or set it to a morning-only schedule.
Check the tempering (mixing) valve is working.

All Chromagen systems should have a tempering valve that mixes cold water in to deliver a safe 50°C at taps. If tap water is above 50°C, the valve is faulty and needs replacing.
Use hot water more frequently in summer.

Drawing hot water regularly during sunny months prevents the tank from accumulating excess heat. Running a bath or the dishwasher in the evening helps.

When to Call a Professional

If the pressure relief valve drips regularly, the tempering valve does not reduce tap temperature, or overheating is frequent, a technician should inspect the system.

Frequently Asked Questions

Is it normal for a solar water heater to overheat?

Occasional overheating in summer is normal, especially if no one is home during the day. The safety cutout is designed for this. Frequent overheating indicates the boost settings or tempering valve need adjustment.

Chromagen relief valve keeps dripping — is overheating the cause?

Yes — when water overheats it expands and the pressure relief valve releases water to prevent tank damage. Frequent dripping means the tank is consistently overheating and the boost schedule should be changed.