Home Forums Hunting & Shooting Hunter's Campfire Central A/C maintenance question

Wife and I acquired a townhouse with central air...a first for us New Englanders. It's a Lenox 13ACD-018-230-02. Would the 24-Hour Hive Mind please give me some clues as to what sort of mintenance a unit like that requires and on what schedule? In general, what should I be looking for in a A/C service business? To many of you, it ain't rocket science, but it's all new to me. Thanks for your time.

Change the filter 4 times a year.

I disconnect the power to my condensing unit, unbolt the fan and motor and gently scoot them to the side without pulling the wires, and wash the coil out with a hose every spring.

Be careful not to spray too high pressure water or bang into the coil and bend the fins down. You’ll have to reach or bend down into the unit to blow the dirt and cottonwood fluff straight out. You should be able to see daylight through the coil when you have it clean. Airflow promotes heat exchange and makes life easier on all your components.

You may also need to clean the A coil in the air handler inside the closet or attic. Cans of foaming coil cleaner work okay in this application since you can’t usually use the hose inside the house.

Change the filters in the return vents often.

Keep the condenser coil clean (the one outside). Hose it down regularly, and have a professional service tech deep clean it once a year with a mild acid wash. That's what dumps the heat that it absorbs inside the house to the outside air. If it's dirty or clogged with grass cuttings from a lawn mower, it can't do a good job of heat transfer.

Change the filter every 45-60 days. Biggest you can do for it is keep air volume flowing. If you have pets in the house go sooner. As others have said clean the coils. Easy to do and there are some spray foam cleaners out there that are good. Lastly when the unit approaches 10 years replace it. The efficiency level has tanked and you are money ahead on utility bills by replacing it.

GreggH

Every time you vacuum, the air filter, every other time you vacuum or every third time, replace the air filter. You do not need real expensive filters, just good air flow with the big chunks stopped. AC units are like a diesel engine, clean oil and clean air, they run and run. Old ACs got 20 years, new get 10 if you are lucky.
Make sure you have a break in the drain pipe with a T fitting in the drain coning out of the drip pan. Pour a bit of clorox in the uprght of the T every spring before the AC is turned on to clear any alge in the pipe. Check the outside to make sure you have a 90 with a short extension down, helps to keep critters from getting in a straight drip pipe and blocking it up.

In the fall, before you turn the heat on, wait for a breezy day, open all the windows and turn the heat on, it will burn the dust off of plates and coils without choking you.

Look into celing fans if you do not have them, with adjustable speeds and adjustable directions to save a bit, a fan blowing makes 78 or so, seem cool.

Many times units with individual AC units have smaller than needed units, like a 2 ton VS a 3 ton, causes them to run constantly and they can not keep up on real hot days, they do not cycle, a good AC setup is balanced for cubic foot size of the home and the air flow it will cycle on and off, every few minutes, to maintain a steady temperature. All registers and doors open, to maintain the balance of air flow for drying and cooling. Plus you must cool or heat all of the interior, the furniture, plus the walls. Turning the temp up for a short time during the day if you leave, does not save anything at all.

Insulation is the key and most condos, apartments or town houses are not in general, real well insulated.

One of the most neglected items in a preowned house or unit is the AC and Heat unit, you might have it services right off.

Who here has replaced an old (25 years) A/C with a newer (higher) efficiency unit and documented the average reduction in KW usage over a year's time? I can't find any A/C contractor that can verify the savings to be realized. When I was still working, I put together several before and after comparison studies between older cast iron boilers and newer Mod-con boilers (connected to existing systems with no other changes) in order to prove to myself and customers that they would see substantial savings.
I agree the coil should be cleaned and the filters changed. Be wary of a clogged condensate drain as well.

I have Hvac guys on my crew. On the filter. buy the cheap ones you can see through and change monthly. They provide the best airflow and save you money. The condenser on mine I wash before I turn it on and I am about to do it again. Wash from the inside toward the outside. You want good airflow here as well. It will save you money to keep it clean. I had a Rehm unit that was undersized when I bought the house. I changed it after 27 years. Have a Coleman now that is big enough. Will easily keep the house cool. Energy bill is the same even though it is more efficient on paper. The guy that installed my new unit was surprised at how clean my A coil was. I told him I changed the filter monthly. He said almost noone changes them like they should.

Did the comparisons you put together prove there were substantial savings? Enough so that the cost was quickly recouped?

We live in a dusty little house and I change the air filter every month during the cold and hot weather. Maybe every 45 days in the off-season.


And I will second Hogwild, buy the inexpensive 3M filters, I wouldn't go with the higher micron as I read they are hard on the fan?


We get the red 1000's on an auto delivery. Only $15 for a filter.

Some myths are being repeated here. First of all, dirty filters don’t let in more dirt. They actually filter out dirt better than a clean filter, but they flow less air. As some have mentioned, the reason to change filters is to keep adequate airflow in the system.

The super cheap filters will let fine dirt and dust through, letting the evaporator coils get dirty quicker than a finer filter. The super fine filters capture more dust and dirt, but they tend to flow less air.

I use a middle of the road filter, rated at 8 MERV. It’s far more effective at capturing dust and particulates than the super cheap blue filters (which basically just keep the AC from sucking up your cat), but is still fairly economical to buy and flows air well. I do have 5 air returns on the first floor, which helps balance the system and allows adequate air flow even with a finer filter. The filter contributes to indoor air quality, especially in a tightly built house.

Finally, I can’t imagine replacing a perfectly functional unit every 10 years and expecting to save enough money to pay for the entire system. Maybe that’s true, but I kind of doubt it. Especially in a climate where you aren’t running the system constantly.

Keep clean filter, clean the condenser every year.

Clean the condenser on your fridge and freezer once a year too

I am brokedick...

I buy brokedick filters and change them every 30-40 days...

Coils... damn... they sucks... but necessary.

i.e. get the coils clean... the rest is cake

When you guys say cheap filters- use the pleated merv 8 filters…Not the true blue mesh filters.

Generally- the primary use of the filter is to keep your evaporator coil clean of dust, not to filter out bacteria and smoke.

Like others have said- keep your outdoor condenser coil clean, your condensations drip pan free of bacteria and slime, and your filter changed as needed, depending on how often your indoor fan is running. Could make sure your indoor blower motor fan is clean too.
If you can inspect the evap coil- do so. It shouldn’t look like this

Yep, MERV 8 is the sweet spot for filtration, flow, and price. Ace hardware house brand is inexpensive and seem to work just fine.

There is a big difference in filters. The cheap cheap stuff doesn't do much besides keep bugs out. Filter media is constantly improving to where you can run a quality, higher efficiency filter today with a lower pressure drop than MERV 7 or 8 from a few years back.
Freudenberg-Vilodon did a study that showed that a 20 thousandths buildup of bio-film on the coils, reduces heat transfer by 20%.

If you can run a 4" instead of a 2" of the same MERV rating, do it. More media (as long as it's the same media) reduces pressure drop, which saves you energy. Never double stack filters. All you do is choke the system and increase energy costs.

Always be sure that you have adequate air flow for the filter that you install. Going MERV 13 in an older system, for example, may actually reduce indoor air quality. Filters only filter particles that reach them, and that requires airflow.

I need a custom size filter, so I buy filters from FilterBuy. I live in a dusty area, so I change the filter every 30 days. I get the MERV 8 filters.

I would like to comment on FilterBuy. It is the best company I've ever dealt with. Quality, service, speed and price. Filters to your front door. Free shipping, so what the hell.

I live in Southwest Florida. My AC is running most all the time. During the three month cooler times it still runs but not 24/7.
I have mine serviced every six months. They clean the coil and the drain. They also check pressures. I replace the filter every two months. I could get by replacing it every three. I buy a box that has four filters. I reorder when I grab the last one them from amazon.

Yes. With natural gas the cu ft used was about half what it was with the old unit, using the old baseboard or radiator emmitters. This is read from the meter and plotted over degree-days of demand. The savings came from burn modulation and outdoor temperature reset feature, in addition to efficient condensing burner. most times the older boilers were not tuned to altitude, so that skewed the result in my favor. Wish an a/c contractor or rep would do this with the equipment they sell.

Sorry my answer is down below. The time to re-coup is probably between five and ten years.