Need AC recomendation

[cm2677]

I know there a lot of AC manufactures out there and they all have the pro's and con's. Currently I am looking at a Carrier 4 ton COMFORT™ 14 CENTRAL AIR CONDITIONER 24ACC4.

I had someone come out and look at my AC unit cause the outdoor unit is not running and he said the condenser fan and compressor are bad.

My current AC unit is a builder grade York system from 2008.

Besides Carrier, what are some other units out there that are just as reliable?

I know I can Google it, but I want to hear from person experience.

 

[Trey T]

The first question to ask is why the condenser fan and compressor are bad. Most of these units today has a copeland compressor, if not all, and they're very reliable.

In a servicing world, from residential to commercial/industrial, the minimum bid you need is 3. In the HVAC residential world, you should get at least 6 bids. If you only have one guy coming, particularly in the summer, there's a good chance he's in it to make a quick buck.

When was the last time you clean your condenser coil?

 

[cm2677]

The first question to ask is why the condenser fan and compressor are bad. Most of these units today has a copeland compressor, if not all, and they're very reliable.

In a servicing world, from residential to commercial/industrial, the minimum bid you need is 3. In the HVAC residential world, you should get at least 6 bids. If you only have one guy coming, particularly in the summer, there's a good chance he's in it to make a quick buck.

When was the last time you clean your condenser coil?

Trey, I've had the condenser fan go bad before, I got it running by taking it apart and cleaning it. That lasted for a few years. When I call for AC the condenser fan does not start-I already replaced the start/run cap because the old on had rust.

As for the condenser motor, they guy did a continuity check on the compressor and he said 2 of the legs were open.

As for cleaning the coil, last month.

 

[Trey T]

If you have a burn out, then critical steps must be taken prior to installing new ones. If not, the new one will die prematurely. Just keep this in mind and be vigilant to communicate this with your tech.

As far as brands, I've only experience (install and service) with goodman, rheem, and american standard (trane). I like Trane, primarily because of their unique spiral fin condenser technology. Trane is like a BMW M3/4 in terms of performance and features.

There's a new technology called "inverter" (DC compressor motor) to modulate refrigerant flowrate and it's a good technology. I don't have experience in them other than mini-splits, but I do recommend the Bosch inverter units that's 18SEER and they're a lot cheaper than Trane or Carrier. A Bosch system of 4ton for about $4K (wholesale), which is cheaper than a 16SEER goodman or rheem - yeah it's weird. These Bosch (or inverter types) systems are like Porsche hybrid.

 

[mrpizza]

Take a look at Trane units. Best coil out there as mentioned.

I have a Trane XV system, works fantastic and is cheap to run.

 

[Fixin'Stuff]

Measure the voltage on the output side of the contactor. A failed contactor will prevent both from running. You can pick up a new one pretty cheap at DA Warden there in Georgetown, if you find that's the problem. They're a DIY-friendly shop. I've bought parts there and had them build return-air boxes for me a couple of times. Pretty nice bunch of folks.

 

[theoldwizard1]

Look for a high SEER rating, above 15. You live in TX, so high efficiency will pay off (people who live in the Midwest/North with short cooling seasons don't need the supper high efficiency)

Inverter technology is good but expensive. To maximize the benefit, you should get a variable speed blower.

 

[cm2677]

Measure the voltage on the output side of the contactor. A failed contactor will prevent both from running. You can pick up a new one pretty cheap at DA Warden there in Georgetown, if you find that's the problem. They're a DIY-friendly shop. I've bought parts there and had them build return-air boxes for me a couple of times. Pretty nice bunch of folks.

Thanks Fixin'stuff. I forgot about DA Warden. I already measured the voltage and it's good.

 

[bonneyman]

Definitely get some more opinions - lots of crooks out there just trying to make a buck.

Ten years old for a builders model ain't bad, but you could probably get more life out of it. Even if the compressor is bad it can be replaced for far less than a new condensing unit. A new CU now would be R410a - your existing system could still be R22. Change one part out means a whole new system. Big expense. Plus - with the next ban and replacement of refrigerants coming - if you can stall going to R410a for a few years you might be able to leapfrog over it entirely and just go to the new gas. Just what I'm telling my customers.

But if you gotta go for a new unit I'd also recommend Trane.

 

[cm2677]

Thanks ducksface, I'll check into it.

But I am glad to say I got it running. Fixin'stuff reminded me of DA Warden her in Georgetown. They had the motor and a matching start/run cap for it.

They are definitely DIY friendly people-as long as you don't act like a jerk.

 

[bonneyman]

Thanks ducksface, I'll check into it.

But I am glad to say I got it running. Fixin'stuff reminded me of DA Warden her in Georgetown. They had the motor and a matching start/run cap for it.

They are definitely DIY friendly people-as long as you don't act like a jerk.

So, the legs on the comp were open simply because it was off on internal overload (i.e. high temp) because the fan/cap went out and let the comp overheat? Sounds like the AC tech you had out was a novice.
If a comp shows open windings check to see if it's hot. If it is, dribble water over it with a garden hose to cool or unplug the power and wait 24 hours. then recheck.
Glad you got the ole girl running again.

 

[TRWham]

So, the legs on the comp were open simply because it was off on internal overload (i.e. high temp) because the fan/cap went out and let the comp overheat? Sounds like the AC tech you had out was a novice.
If a comp shows open windings check to see if it's hot. If it is, dribble water over it with a garden hose to cool or unplug the power and wait 24 hours. then recheck.
Glad you got the ole girl running again.

When I was with Copeland, the most common problem found when compressors were returned under warranty was (imagine drum roll here)...

Nothing at all!

We really did tear down and test warranty returns. And that's right, perfectly good compressors were returned because the tech could not find the actual problem, so he kept changing parts until the customer stopped calling him back out.

 

[cm2677]

I think what happened was a thermal switch had opened. I took a continuity tester to the same lines the AC guy did lastnight and today they checked out fine. Right now the AC has been running for half and hour and the temp dropped 3 degrees. Not bad for it being almost 100 outside.

I'll be glad if I can get a couple more season out of this unit. It is electric heat and I want to convert to a heat pump.

 

[8mpg]

I myself will be going to a Mitsubishi system next time around. I couldnt afford it at the time and went with a Rheem heat pump system. Mitsubishi systems are variable refrigerant flow meaning it can ramp up or down depending on the actual load. Lots of the American branded systems are starting to go this way but often dont go down as far or are set multi-speed systems.

As far as Carrier... while this may be isolated event. My dad just had a variable speed one installed. 5ton multi-zone system and has had a couple issues already. Its less than 6 months old. One bad thermostat, one bad control board and a bad switch "that wasnt crimped well from the factory".

 

[Trey T]

If the condensing unit (heat exchanger and fan) is working properly, then you got a problem w/ the compressor pump. Your compressor motor is overheated causing the internal thermal overload to trip, this can be caused by low refrigerant (not enough fluid moving thru to cool off). Get your system checked out again.

The thermal overload can be prevented if you add a fused disconnect by the unit. If the motor RLA is rated for 25A, then getting a 30-35A fuse will prevent the overload. If you let the thermal overload trips too many times and too frequent, that compressor will fail catastrophically.

 

[bazar01]

I think what happened was a thermal switch had opened. I took a continuity tester to the same lines the AC guy did lastnight and today they checked out fine. Right now the AC has been running for half and hour and the temp dropped 3 degrees. Not bad for it being almost 100 outside.

I'll be glad if I can get a couple more season out of this unit. It is electric heat and I want to convert to a heat pump.

Its possible the condenser fan stopped running and compressor kept running and tripped the thermal overload on the compressor. Watch your condenser fan motor.