Dirty fresh or combustion air intake screen similar to the one in this picture will cause the furnace to not get the proper air it needs to run, Because of a negative pressure in the room. This negative pressure will cause air to be brought into the room through the only duct to the outside which is the furnace exhaust vent. The furnace will have a back draft safety switch to protect the home owner from carbon monoxide poisoning and when the safety switch trips it can be easily reset, But once reset the reason for it triping in the first place must be addressed .
Click here to see my Post on protecting your home “Alarm for home”
Thank you for visiting my blog I would appreciate any feedback I can get, Please leave a comment on whether my information has helped you. I am always interested in more topic to write so feel free to leave a comment asking about anything related to HVAC-R(Heating, Ventilation ,air conditioning, refrigeration).
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Hey there from many miles away! This is just what I was thinking of, and you wrote it nicely. Thank you
Thanks for the comment you sent on nov 18/2012, it feels good to know people are getting good info off what I write . I just started this website last month as a project,You are the first to post comment.
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