Before you do anything silly/expensive this is usually paired with the room
thermostat and receives wireless
signal from it and the red flashing light is probably telling you that the
batteries need changing in that one.not the WR1. A simple and inexpensive fix.
Best to use Duracell or similar but ordinary batteries will work but don't
last as long.The batteries in the WR1 should be good for 10years or more.

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