BoilerFaultCodesYour solar heating system is not circulating fluid quickly enough between the roof panels and your boiler setup.
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 low.
What causes this fault?
This fault occurs when the solar heating fluid is not moving through your system fast enough to transfer heat effectively. The most common reasons are an aging circulation pump that is losing power or solar fluid that has degraded and thickened over time, causing a blockage. It can also be triggered if air bubbles are trapped in the pipework, preventing a smooth flow between your roof panels and the cylinder.
This code is most frequently seen during the summer months when the solar thermal system is under the highest thermal stress and working at maximum capacity.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like 59202 — no call-out fees, no surprises.
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