Just bought a new house that has an A/C unit thats at least 30 years old. Worked fine for a couple of days, then the problems started: 1) The outside condenser unit runs continuously 24 hours a day, regardless of what the thermostat temp setting is. 2) The pipe from the outside condenser going into the house gets ice cold and freezes over within 10 minutes after starting up. 3) After the pipe freezes up with about a 1 inch thick ring of ice around it, the outside condenser unit starts making really loud grating noises. The air coming into the house is nice and cold, but I know that the pipe freezing up is not supposed to happen and the noise sounds really bad. The only way to shut off the outside condenser is to flip the breaker outside the house that controls it. We replaced the thermostat control unit and it didnt fix the problem. I set the thermostat control to 70, 75, and 80, and the same problems always happen. Questions: 1) The outside condenser is not supposed to run 24/7 right? It should only turn on when the temp gets too hot and the system kicks in, right? 2) Talked to an AC guy on the phone and he said to me "you should never turn on the AC when the outside temp is 70 or less." Well I call ******** on that because the thermostat is supposed to control when the unit comes on or off. I dont know anybody who manually shuts down the AC unit every time the weather outside changes, they let the thermostat control do that job for them. Am I correct in assuming he was just blowing me off because he didnt want to come out to my house? 3) The outside pipe getting cold and freezing up is NEVER supposed to happen right? Do you think its a bad wire somewhere in the house or a short circult that is driving the outside condenser to run 24/7? Its obviously not the thermostat control unit, because we changed it and its still happening. Since I do have the home protection thing, I'm hoping that the AC guy who comes to my house in 2 days says that I need a whole new inside and outside unit so I can get a $8,000 brand spanking new system for my low service fee of $75
1) Yes. 2) I think you shouldn't force the A/C to run when it's really cold outside (close to freezing temps) because of risk of damage to the compressor. But 70 °F should definitely be OK. 3) Right, pipe shouldn't freeze. Sounds like somehow your compressor is running continuously, which is very bad. Also, if the condenser is really 30 years old, it's way past it's expected life. Don't let the compressor run all the time, or something bad might happen, like a fire. Is there a name plate on the condensing unit? If so, take a picture of the data on the name plate, and post it here. I might be able to find the year from the serial number.
30 year old unit ? outside freeze up probably due to low refrigerant ... can you say leak(s)? invest in a new system ... even if you get this one fixed, it will eat you up with high electric bills due to its inefficiency compared to newer units.
Your short term fix is to get some more refrigerant (freon) added to the system. You've probably got at least one leak somewhere in a unit that old. Long term, you're looking at a new A/C system.
Agree with above. You have a leak in your coil (usually inside) or the freon (or whatever they use now) is low. If you are going to be living there > 3-4 years, I would invest in a whole new system. It should have a 1 yr warranty on parts & 5 yrs on service. A new unit both inside & outside should last about 10 yrs.
If you end up buying a new system and can wait until Memorial Day weekend, the state is having a "sales tax holiday" on energy star efficient appliances, including AC units. You might be able to save yourself a bit of money.www.window.state.tx.us/taxinfo/taxpubs/tx98_836/
Is the outside freeze due ONLY to leaks, or can the outside unit running 24/7 cause it to freeze up without any leak?
I'm going to piggyback onto this post with my problem. Right now my AC is running, but there is no air coming out of any of the vents. I just changed the air filters (which were filthy) but it still doesn't work. I also noticed that the pipe going to the house is getting ice on it. Ideas?
Hose down the iced over component; IIRC, that's a short term solution that should get you working. I do work for Hank's A/C & if you do call them, tell Millie or Linda (whoever answers) that Mark with Ranch Hand Roofing sent you. I don't know if it will get you anything free, but it will probably get some brownies for me. 512.258.1499 The Link
Somebody on another board mentioned turning the heat on to defrost it. I did that (before I saw NCAA's post) and it worked. A/C ran like a charm this morning and wasn't frozen at all.
brandon, did your home inspector mention anything about the AC before you bought? I ask because an AC issue has happened to us twice shortly after closing on homes and neither time did anything come up during inspection. Neither time required a whole new system, but both were rather pricey and although they would have been covered by the homeowner's warranty, our preferred AC folks weren't contracted w that warranty co. and we didn't trust just some random repair guy. Does the regular home inspector not look at the ac/heat or something? It seems like a pending failure would show some early signs, but maybe not...
Horn on the Bayou- either your evaporator coil inside is completely freezing up, or your blower motor is toast. Try turning the fan on but not the air conditioning and let it run for an hour or two, if the fan seems to be drawing air from the intake. If the fan isn't drawing air in frmt he intake then you probably have a blower issue. Costs usually less than $100 and is replaceable yourself, as I have done it in my old condo. Two wires and about 6 screws. IF the Fan is working run the fan for several hours with the thermostat set at a setting high enough NOT to come on. You should at the end of this have at least air blowing out the vents, Freezing up outside, and general hot or cold pipes inside- Oftentimes outside freexe up is an indicator of low freon. The best way to tell whats happening with your unit if from the interior unit. you should have one line comeing in cold and the return line coming out hot. Thus creating the heat transfer. If the unit is frozen in the evaporator coil you will get the cold but not the hot return line. If there is a problem with low freon you will not have either line beign sufficiently hot nor cold. If frozen outside and neither interior lines sufficiently hot and cold then probably not enough freon. Oddly- too much freon can cause the unit not to coll properly. happened to my buddy and after ahving one company wanting to sell him a new system $6000, he got a second opinion and the tech found the other tech had overcharged the unit. Removed some freon and it worked perfectly. IT is POSSIBLE that with a home for sale the Freon could be at either a too high or too low level, especially if there was a problem with the unit they were trying to disguise. good luck but check the interior intake and return lines to get a better idea of what is going on. We got a 1 year home warranty that took care of our compressor issue about 3 months after moving in. however I probably should ahve just bitten the bullet and gotten an entirely new system. having the exterior unit not shut off sounds bad. My buddy had success with Strand brothers in the honesty department saving him a new unit.
OK, the AC guy came today. He said the outside unit had a bad contact switch that was causing it to permanently stick and run the unit 24/7. He replaced it and now everything is fine. However, he did have some bad news for me. He said its an old system and hanging on by a thread. He said he could get me a new outside unit under my warranty, but that by state law, once you replace the outside unit, you are forced to replace the inside unit too because of efficiency matching regulations. He said he doesnt think my warranty will pay for a new inside unit because technically its not broken.
If you got a quote from your A/C guy, call around to get some competing quotes. I think I mentioned someone up above; call him as well.
So, I checked with Hank. "State law" does NOT require you to change both @ the same time, only the city if you want the rebate (as discussed / ). It IS a good idea to balance them both out so that they are working @ peak efficiency, but you do NOT have to make the change now; you could wait to do the inside / air handler if you didn't have the $$ now (he didn't speak to the AHS because he said he would need to look @ the system as a whole to let you know what's right & what's wrong about the system as a whole). He was taking 3 calls while he talked to me, so I hope I'm remembering this next part right: And... IF you wanted to upgrade to the R410a, which is the more environmentally friendly setup, then this has to be a total inside & outside change. He said they just put out a $ 19.99 mass mailer & if you wanted a service call & are in the Oak Hill / South Austin area, they can come out to give you the same service call / inspection for free... gotta call Hank directly (not the office) & let him know I gave you the info. Send me a PM for his cell phone #.
One simple thing check the evaparator coil make sure its clean. They have to remove it from the inside unit. We moved in a house with the same problem and it had a ton of dog hair coating it.. 250.00 later it works fine..
Just curious, but what brand was that old model? That one hell of a lifespan for a condenser. I just replaced the motor in my condenser and its only 8 years old, but working great now. I have a Trane My dad happily replaced his system after 20 years of service last year. Not sure what his was.
