central a/c service

[briansol]

My oil company is emailing me about having a service done. I've been here at the house 7 years now and have never serviced it, other than changing the air filter for the attic fan.

what else do they do? everything works fine.

 

[blujacket]

Oil the fan motors, maybe clean the condenser coil.

 

[woodgeek]

Did they install it? Having the indoor coils cleaned every few years is prob not a bad idea....might be DIY-able. Studies have shown that HVAC systems with regular maintenance have **shorter** lifetimes on average than those that don't. Presumably a few bad apples are sabotaging older systems to get a replacement contract. Personally, I don't trust the oil techs these days...I'd have an HVAC company service AC if I did it at all.

 

[semipro]

Cleaning the outside coil is easy DIY.
If you keep up with your air handler filter changes cleaning the inside coil should not be necessary very often.
I'm thinking that most newer air handler blower motors have sealed bearings and no longer require lubrication.

 

[briansol]

It came with the house when I bought it in 2007. I assume it's original from the home build in 1997, not from any heating/cooling company. I never had it serviced since i've been here since 2007. I change the air filter yearly as it gets pretty dirty after pollen season. that's all I've done. It seems to work mint with no noises/etc but I want to make sure i'm not losing efficiency by skipping out.

I have the exchanger outside of course and the main unit is in my attic above the intake air filter in the hall way. It doesn't seem to have obvious service parts. Just lots of stickers about unplugging the breaker before opening covers and such.

orig owners didn't leave me a manual for it and I can't find a brand/model on it anywhere.

 

[semipro]

It came with the house when I bought it in 2007. I assume it's original from the home build in 1997, not from any heating/cooling company. I never had it serviced since i've been here since 2007. I change the air filter yearly as it gets pretty dirty after pollen season. that's all I've done. It seems to work mint with no noises/etc but I want to make sure i'm not losing efficiency by skipping out.

I have the exchanger outside of course and the main unit is in my attic above the intake air filter in the hall way. It doesn't seem to have obvious service parts. Just lots of stickers about unplugging the breaker before opening covers and such.

orig owners didn't leave me a manual for it and I can't find a brand/model on it anywhere.

If the air handler is in an unconditioned space you're much more likely to be losing efficiency though air leaks at the unit itself and through ducts within the attic. In general, putting the HVAC units and ductwork in unconditioned space is undesirable not that you have much choice. I'd suggest keeping the outdoor unit clean and fins straight, maybe shading it, and making sure airflow is unobstructed around it. In the attic I'd make very sure things are insulated and sealed well.

Edit: a year on the filters seems long to me but maybe your house is much cleaner than mine

 

[briansol]

I only use the a/c for any amount of time in july and august. sometimes a 3 week stint. otherwise its off and on when I can't take the humidity any more. So, I think a year is fine.
My house is clean. I'm a bit of a neat-freak.

The attic area does get hot in the summer. I do have a ridge vent and opposite wall vents as well though so it doesn't get 140+ like some houses I've been to without them.
the ducts are insulated themselves, and sit on/in/under blown-in insulation in the attic. if there's a leak, i'm not going to find it without tearing apart the attic.

The unit outside is probably the part that is in the worst shape simply because it's outside. I covered it, but the tarp blew off at some point in the winter and I didn't notice it before 3 feet of snow was sitting on it. the blades look fine, though. maybe just a little surface rust on 'em.