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Honeywell L7224U controller Err 5

Swilliam
Swilliam Member Posts: 1

Just replaced my L7224U controller because the old one got fried when using a portable generator. So I simply put the wires back in the same positions in the new unit. But I get an Err 5 code, which means "Low Line; check L1-L2, 110Vac" There is 121 V across the L1 and L2 wires, same as for the rest of the house. Any ideas?