General Residential A/C Maintenance Question

[Howard Duncel]

My Carrier Performance system is now 12 years old and is performing well.  However, after this many years I’m wondering if it would be a good idea to open the plenum and evaporator cabinets to clean the evap coils, remove accumulated sludge and debris, etc.

thoughts?   Thanks in advance 

HowarD

[Vance R]

55 minutes ago, Howard Duncel said:

thoughts?  

General maintenance is usually recommend every year, also don't forget the condenser coils. 

[WOOKIE]

Cleaning the condenser is easy.  I prefer just to use a plain water with a jet spray to wash out the dirt from top to bottom being careful not to bent the fins.  Unless you have alot of debris inside there is no need to remove the top. If you do then spray from the inside out top to bottom.  I don't ever use a coil cleaner because 90% are corrosive and, if you don't remove the spray it will destroy the coils.  while you are there check the run capacitor (while the power is off) to see if it is within spec's.

The evaporator coil is very different, the dirt and debris is inside  making it difficult to clean.  Access is made by removing the A coil front plate . Then being careful not to break a feeder tube's reaching inside the coil with a small plastic brush . If you have a down flow unit the dirt will be on the outside of the coil and you don't have to remove the side cover plates..

At 12 years old the formicary corrosion has taken it toll on the evaporator and, there is alot of rust on the slabs where the feeder tubes go into the coil ( unless you have an all aluminum coil ) disturbing these can result in a freon leak. There is a product in the supply house you can spray on the evaporator coil without having to rinse off. It traps the dirt and removes it down the condensate drain line. I have use it for years.

Pull the squirrel cage and clean the blower wheel. At that time check the fan capacitor (micro farad) to ensure it is within specs.  They are so cheap  you can just change it.

Don't forget to flush the condensate drain line dirt build up over the years blocks the drain line. 

As far as the ducts, they are normally not an issue. There are duct cleaning companies but, it can get expensive.

[Howard Duncel]

Thanks for the responses.  I perform basic maintenance annually including flushing the condenser coils and condensate drain lines, as well as replacing the start capacitor.  As further preventative action I replaced the condenser fan motor last year.

Thanks for suggesting replacing the squirrel cage motor cap - I honestly hadn’t thought of that, but shouldn’t be too difficult.

My system has the Carrier “N” evap, and if memory serves its a 100% aluminum design so  hopefully has little or no corrosion.

Cleaning the evaporator is just more difficult as the plenum and evap chassis are sealed with mastic, and I’ve never disassembled it for access.  My primary thought was cleaning for increased efficiency, but inspection for current and potential future issues is probably more important.  I’ll look for the evap cleaner.

With Fall coming up, attic temps should drop and I can comfortably take a look.  May as well check the furnace igniters while it’s open …