BoilerFaultCodesTechnical 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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