BoilerFaultCodesTechnical description
Mass flow rate in solar system for collector group 1 is too low.
What causes this fault?
This fault happens when the sensors detect that the solar fluid is moving too slowly or not at all through your roof panels. The most common reasons are a failing circulation pump, a blockage in the pipework, or the solar fluid becoming too thick and degraded over time. Without proper flow, your system cannot safely transfer heat from the sun to your hot water cylinder.
This fault is frequently triggered during the first warm days of spring or summer when the solar system is required to work harder after sitting stagnant over the winter.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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