Time for the annual cleaning again. I was surprised to find it this dirty. My unit is an upflow model with the air return at the floor, the unit in a closet in the living area and the ductwork in the attic. Looks like my air return plenum needs some additional sealing work. The middle looks black because the camera is looking straight through the fins. The left is brown because that's wet dirt/sludge that got past the filter or came in from the plenum box. The right side is silver because we're looking at the side of the fins. This evap is ~ 23yrs old now so some of the aluminum is wearing.
Cleaning involves spraying both sides with coil cleaner, letting it foam, brushing it up & down with the fins to remove/loosen the dirt, then flushing with plenty of water.
It takes me awhile to do this as I have to pull the blower for better access, remove the top of the A-frame coil, and lie on my back looking up, while wearing goggles to spray the coil.
I learned something new about one particular type of coil cleaner. I bought a spray can of it from a A/C shop for about $12. I noticed the ingredient list said "surfacants and 2-butoxyethanol". Turns out that Tuff Stuff multi-purpose foam cleaner contains the same two ingredients plus sodium metasilicate, which is a detergent. Tuff Stuff is about $3/can on sale. Why pay 4x the cost for the same thing??
I used to buy the gallon jugs of concentrate. They're more powerful in my opinion. But the place I bought the can didn't stock what I usually use.
While I had the blower motor out, I removed the end cap to have a look at the oil padding:
Looks a bit dry. So I added some M1 10w-30 I had on hand via a syringe to fill it up again:
Looks like I'll have to do some additional sealing of the plenum box. I still have some mastic left over from the new duct installation. I'm also curious if I could reduce the turbulence into the bottom of the A-frame coil by installing a piece of the plastic light diffuser that looks like a bunch of little boxes. Often used in commercial overhead flourescent fixtures. Sort of an 'air guide'. As the coil pictures prove, the dirt isn't evenly distributed across it.
Cleaning involves spraying both sides with coil cleaner, letting it foam, brushing it up & down with the fins to remove/loosen the dirt, then flushing with plenty of water.
It takes me awhile to do this as I have to pull the blower for better access, remove the top of the A-frame coil, and lie on my back looking up, while wearing goggles to spray the coil.
I learned something new about one particular type of coil cleaner. I bought a spray can of it from a A/C shop for about $12. I noticed the ingredient list said "surfacants and 2-butoxyethanol". Turns out that Tuff Stuff multi-purpose foam cleaner contains the same two ingredients plus sodium metasilicate, which is a detergent. Tuff Stuff is about $3/can on sale. Why pay 4x the cost for the same thing??
I used to buy the gallon jugs of concentrate. They're more powerful in my opinion. But the place I bought the can didn't stock what I usually use.
While I had the blower motor out, I removed the end cap to have a look at the oil padding:
Looks a bit dry. So I added some M1 10w-30 I had on hand via a syringe to fill it up again:
Looks like I'll have to do some additional sealing of the plenum box. I still have some mastic left over from the new duct installation. I'm also curious if I could reduce the turbulence into the bottom of the A-frame coil by installing a piece of the plastic light diffuser that looks like a bunch of little boxes. Often used in commercial overhead flourescent fixtures. Sort of an 'air guide'. As the coil pictures prove, the dirt isn't evenly distributed across it.
