Evcon Furnace 3 Flashes Combustion Air Switch Failed to Close. How Do I Repair It?

Coleman Evcon Model as36a264t LM Hi I have the above model forced natural gas furnace. I started getting the three blinking lights indicating the pressure switch failed to close. I am not sure what to do. I removed the rubber hose and mde sure nothing was stuck in it and blew through it (hose...

I have 4 industrial boilers that range from 40klbs/hr to 60 klbs/hr. Currently, we have 2 types of air proving switches: Cleveland controls AFS-951 and an old Honeywell that I cannot read the part number. My operating combustion air pressures run from 8-20"H2O. The Cleveland controls switch...

Ihave an evcon direct vent forced air unit model # DGAT056BDD and when it faults out a get a light that flashes 4 times.I can cycle power and reset it and it may no do it again for another week. Thanks

I need to know, what is size required (duct size) for combustion on a furnace. It is a formula that you use, it is how many sguare inches for some many BTUs.

I have just finished my basement and my furnace is now in a room about 20 x 20. I had installed double doors (solid not vented) to enter the room which is also being used for storage. My question is do I need to add some kind of makeup air for combustion by installing a grill in the wall? ...