Low Warning
59201 on Worcester Bosch Greenstar CDi Compact

Your solar heating system is circulating liquid too quickly, which usually means a sensor is misreading or the pump speed needs adjusting.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Mass flow rate in solar system for collector group 1 is too high.

What causes this fault?

This fault occurs when the fluid in your solar heating circuit is moving faster than the system's safety limits allow. It is usually caused by a malfunctioning flow sensor providing incorrect readings or a solar pump that has been set to an unnecessarily high speed. In some cases, a glitch in the solar control module can also cause the system to mismanage the circulation rate.

This issue is most frequently noticed during the summer months when high solar gain triggers the pump to run at maximum capacity more often.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

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