Colman Evcon electric furnace

[katlamb]

Hello we have a Colman Evcon electric furnace model # eb15a, built/installed spring 1994, it recently started making a buzzing noise when the heat is on. It doesn't do it every time the unit kicks on but when it does do it it is very loud. We used a stethoscope and kinda narrowed it down to somewhere in the fan/blower area or in that general area anyway...we are wondering is it safe to run it until we can get a service man here next week? Also if you could give us a general idea of what it may possibly be, my mechanic husband thinks it may be a bearing in the fan going out but alas he isn't an HVAC specialist. Also there is what looks to be mold growing on the underside of the condenser, what could be causing that? Any help as soon as possible would be great!

[DaleM]

Buzzing noise could be an element going bad. Most of the time when the blower motor is failing it squeaks or squeals.

As for mold on the condenser, that part of the AC is outside. You are looking at the evaporator coil. Mold growing there because there is moisture/condensate on it when it is operating. Maybe the drain tube is clogged and you're getting an overflow of moisture out of the pan. Pull the tube and put a shop vac on it. That should clear it. Also make sure the nipple coming off the pan is clear as well.

[katlamb]

Thanks for the quick response, so if its the element going bad we will probably need a new furnace? Or can the element alone be replaced? Also we don't have any back up heat, how likely is it to stop working out without warning? Should we fix it immediately or do you think we can get away with using it another couple months? It hasn't buzzed any the last 10 or 12 times it has kicked on.

[DaleM]

There are 3 elements in the furnace on 2 seperate assemblies. Both assemblies are replaceable. Not until it gets REALLY cold will you notice one not working. When 2 go down it takes the furnace a long time running to keep the house warm.