AC Tune Up

[Insomniac]

Does anyone get this done? If so, do you do it annually (or some other interval)? Seems like I need to do something. 80 degrees out, 84 in the house. Turned the AC on and set it to 78. 2 hours later, it was down to 80 in the house. Any advice?

[indyfan31]

Other than cleaning/replacing filters I can't imagine anything that needs to be "tuned up"; although I keep getting offers from one local HVAC shop. I guess you could check for coolant leaks. I have had the same situation happen to me as you mentioned but I attributed that to Edison's control of of the compressor during "peak usage" periods.

[Gnam]

I am not an HVAC expert. It sounds like the thermostat is working. It's measuring the temperature and sending a signal to the unit to turn on. Also, it sounds like the blower is working, so the unit has power. The only other faults I can think of would be the electric motor that pumps the coolant, or the coolant itself.

One time at work everyone closed their vents because they didn't like the draft. With no where to go, the cold air backed up into the ducts and froze the coils solid. The frozen coils blocked the flow of air, which meant no AC for anyone. Then they all complained about the heat. Good times.

[cameraman]

You could have a coolant leak. You don't need to have the pressure checked every year but it sounds like you're due. Turn it off until you get it checked. Running the compressor without coolant will kill it.

[dando]

I'm not a fan of service contracts, but service every other year is a good idea. Note that we had the HVAC (x2) replaced a couple of years for $15K (two compressors and two furnace units @ <10 years). :saywhat: We had a coolant leak and failed capacitors, which I think was caused by a nearby lightning strike that also took out a microwave and under cabinet lighting. You definitely have a coolant issue. The biggest issue we had was the low coolant issue made the compressor overwork, and cause the furnace to freeze up, and when the furnace/blowers shut down, they thawed and left moisture goodness in our $75K finished basement. :irked: So the moral of the story: an ounce of prevention == a pound of cure.

-Kevin

[KLang]

We have a service contract for our three systems. They are checked out spring for the AC and fall for the heat. I think it is about $300 a year. One advantage of service contract is that when something fails, inevitably on Friday afternoon we can be sure to have someone to fix it that day or the following day. No contract? You will sit and sweat for days waiting. Of course the weather here in Texas is kinda rough on AC systems. :)

[mapguy]

EPA certified here... Take a meat thermometer and stick it in the return air duct beside the furnace. Take a reading. Then stick the thermometer in the plenum (duct above the furnace) and take a reading. Ideally there should be a 20 degree split.

Things that a homeowner can do to improve the performance.

The air filter is really important. A badly clogged filter will severely affect cooling.

How clean are the cooling fins on the outdoor condensing unit? I remember in upstate NY the cottonwood seeds that would fly around in spring loved to collect on them. Take a garden hose and CAREFULLY go up and down in the direction of the fins and wash off any debris.

How old is the unit?

Edit: The house will take time to cool down. Ideally set the t-stat for 75 then it doesn't have to work hard to cool it down when you are at home.

[Insomniac]

Here's what they mailed us:

12 Point Check

Filter and change if needed
Belt for wear & proper tension
For loose set screws on pulleys
And oil blower
Thermostat & blower cycle
Temperature drop across coil
For signs of refrigerant leaks
Freon pressure
Wash condensing unit
Evaporator for blockage of air flow
Condensation drain
Tubing for excessive vibration


They check all that for $95. I guess they don't actually fix/repair/replace anything though. "Additional repairs, if needed, will be quoted at time of service. Filter, freon, or freon reclain will be an additional charge." (Maybe they'll tighten the loose screws. ;))

We change the filter often. When you guys say coolant, is that refrigerant or freon?

[dando]

We change the filter often. When you guys say coolant, is that refrigerant or freon?

It's whatever they use these days. If your unit is old, they may need to replace it since they can only use the CFC-friendly stuff these days.

http://en.wikipedia.org/wiki/Refrigerant

-Kevin

[mapguy]

Belt for wear & proper tension

[/LIST]



Belts? If you still have a furnace with belts then you need more than a tune up... :gomer:

[Wheel-Nut]

Living in southeast Texas the AC is a very important appliance in the home.

I have a company come out each spring and give the AC a check up.

They clean the the condenser coil out side. They make sure the evaporator coil is clean and free of dirt. The check the blower fan and check the charge of freon.

[nrc]

I notice that the flexible conduit that feeds the compressor outside has come lose at the junction box on the back of the house exposing the wires. Should I call an HVAC guy or just an electrician?

[cameraman]

I notice that the flexible conduit that feeds the compressor outside has come lose at the junction box on the back of the house exposing the wires. Should I call an HVAC guy or just an electrician?

Either could do it, call the one that costs less.

[dando]

I notice that the flexible conduit that feeds the compressor outside has come lose at the junction box on the back of the house exposing the wires. Should I call an HVAC guy or just an electrician?

Have Missy do it. ;) If it's just the conduit w/o exposed wires (no exposed metal), it should be an easy DIY fix. But that's just me having wired a basement finishing years ago in my younger days.

-Kevin

[mapguy]

Actually getting an HVAC guy would be cheaper. In NYS you only need to be licensed if you touched the sealed system. Anything else is fair game. Electricians, being licensed, are more expensive.

[Insomniac]

Well, the tune-up turned up nothing last year, but this year it hasn't been cooling well the last couple weeks and got worse today. Had them come out, freon leak. They recharged it, but it's just temporary. ~$1500 repair and no warranty, or ~$3k to replace it. 3 Ton Trane, SEER 13 (any higher SEER and we'd have to replace a lot more to accommodate). Our current unit is 2.5 ton. Said we were on the edge between 2.5 and 3 ton. Seemed trustworthy. Is $3k a reasonable price to install a new AC? Should've asked, but how much less would a 2.5 ton be anyway? BTW--Warranty ran out in 2013...planned obsolescence?