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Coleman DGAA070bdta 3 flashes & 4 flashes.

What would make my furnace flash 3 green lights until the Upper limit switch is toggled, then flash 4 green lights until Upper limit switch is toggled again. Blower does come on. Does not attempt to start the ignitor.

Replaced the following this year:
025-35358-000 Upper Limit Switch (3 flashes indicated this needed to be replaced)
s1-025-35358-1000 Limit Switch (4 flashes indicated this needed to be replaced)
s1-024-27666-001 combustion air booster (pressure switch)
3 amp fuse (previous one was not broken or arced, replaced just in case)

Replaced Ignitor last year:
1474-052P Ignitor

I am not sure what to try next. I am proficient in DIY and mechanically inclined, so changing parts out is not a problem at all.

Seen your posting today on your error code 3 & 4 problems. I read the owners manual, for your furnace, and it list several problem areas for error codes 3 & 4. My general impression is that limit switches generally trip from over heating the combustion chamber as a result of some kind of air restriction. The easiest air restrictions are dirty air filters (owners manual states do not use pleated filters), open air registers in the rooms, and a broken pressure switch hose. These areas are the easiest to check out. The other areas shown in your owners manual get to be more expensive and require more serious trouble shooting. Hope this helps you if you are still having problems. Best regards