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Error code reference
Lennox Furnace Error Code DIAG#1: Simultaneous Flash / DIAG#2: Simultaneous Flash
Power ON, normal operation; increased flash rate indicates a heating demand.
SourceLennox GHR26 Series - Service Manual: Gas FurnacesPage 8 (Table 1), Page 11 (Table 6)
Where this code is documented
1 manual in the MyPros+ library documents this code for Lennox furnace.
Models covered by the manuals that document this code
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