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Douglas, HVAC Technician
Category: HVAC
Satisfied Customers: 3089
Experience:  Manufacture Rep for Major Brand, Technical Trainer, NATE
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G71-MPP series Lennox furnace (new 2009) shut down. Error code

Resolved Question:

G71-MPP series Lennox furnace (new 2009) shut down. Error code flashing E228. Do I need a technician? Or just advice on how to restart? Changed very diry air filter.
Submitted: 6 years ago.
Category: HVAC
Expert:  Douglas replied 6 years ago.
Hi, I'm Douglas and I am here to help you resolve problems with your heating and cooling equipment.

This error says "Unable to perform successful pressure switch calibration".

Now this may be something as simple as going outside and checking to see the vent pipes are not blocked by ice, snow, leaves, toys or whatever. If its not that, you can open the furnace and locate the rubber tube (usually a square tube). that leads to the pressure switches. remove them (remember how they went) and blow them out to make sure no water has gotten into them.

If neither of these take care of it, it may require a technician. There arent alot of user friendly components in that furnace.

Douglas and other HVAC Specialists are ready to help you
Customer: replied 6 years ago.
thanks much. furnace started up after blowing out the tubes. No evidence of water, but hey, success is success.