Low Warning
Fault 59 201 on Worcester Bosch Greenstar CDi Compact

Your solar heating system is moving fluid too quickly through the roof collectors, which may indicate a settings error or a faulty sensor.

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 system is circulating at a rate higher than the system's design limits. The most common reasons are incorrect settings on the solar control pump or a malfunctioning sensor that is misreporting the speed of the liquid moving through the roof panels.

This fault is more common during the summer months when high levels of solar radiation cause the system to operate more frequently and at higher intensities.

Engineer required

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

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Related fault codes

59 202View →

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