Becoming Quietly Cool
Previously on this blogI mentioned we've been having many problems with our upstairs air conditioning; more specifically with the inside air handler. The unit is about 8 years old and over-sized for the area, so it forces a high volume of air rushing a very short straight distance through undersized ducts to a vent in the bedroom. It's loud - very loud - sounding like a wind-tunnel or jet airplane loud. It should have been repaired or replaced by the builders before the condo conversion. About a year ago it developed a slow leak in the coils and the coolant has been refilled twice just to keep it cooling. Then last week during an electrical storm the blower stopped working for no apparent reason and some wiring had to be tightened to bring it back to life.
The handler is dying and we knew we'd never have peace or be able to sell the house unless it was replaced. This is an expensive project costing between $2k-$5k, so we needed to hold off as long as possible in order to get the funds together. It was difficult to find someone willing to do the work at a reasonable cost. The handler is inside a very narrow 3rd floor closet, hanging above our hot water heater and plumbing, all of which was obviously installed afterwards because you can't remove it without destroying something else. The closet itself is in a narrow hallway. Not an ideal working condition.
Some wanted to replace it, some wanted to replace pieces of it, and some wanted to try to weld repair it. All these proposals came at various prices from people having a range of competent and incompetent skills. We eventually found someone willing to go through the lengthy pain of swapping the handler out at a fair fixed price. This company proposed replacing it with a slightly smaller TRANE model. The TRANE has a variable blower startup to address the noise levels, and is compatible with our existing A/C compressor. These people were nice, honest, and had a good reputation for similar work for others in this town. This would be their first job in my townhouse community and there are a lot of unique challenges.
The rest of this entry describes highlights of the replacement effort. The people performing the work were nice and knowledgeable. They knew dealing with my townhouse design for the first time would be a learning experience, so surprises that occurred along the way should not be viewed as something done right or wrong.
Saturday MorningAbout 8am we got a call that the A/C repair crew was on the way and would be there shortly. It was expected that this job would take most of the day, with them leaving around 3pm. We locked the cat up in the guest bedroom with food and a litter box, and moved my car out of the garage to give them work space. Three people arrived 10 minutes later. One was the company owner, the second was the skilled laborer (engineer), and the last was a large, strong young man to assist (assistant). They completed preparation work such as laying down drop cloths, bringing in tools, removing the closet door, turning off breakers, etc. They also turned off the hot water because the heater was in the same closet as the air handler. I stayed nearby on the computer or watching television while they produced various conversational and hand tools noises. Cindy stayed downstairs where it was cool.
Hurdle #1 - Money
Around 9:30am I had to run a financial errand to cover the costs of this repair. Yesterday we had a certified check made out to them and drawn from our equity account. It should have been made out to us so we could deposit it into our checking account and pay them whatever final amount was needed. I had no idea what the final bill for this workwould be, just that it would be below a certain amount. I drove to one bank and waited in a long line to have the check corrected, then drove to another bank to have the check deposited. The whole adventure took about 45 minutes before I was home again.
Hurdle #2 - Pipes
Eventually their work reached a point where the current handler was ready to be pulled out, but there was not enough room due to the hot water heater and plumbing. The engineer called me over to discuss his plan to cut away all the PVC pipes and reconstruct them later. This made me very nervous; it would take extra work and time, plus I had no idea of his abilities to do that correctly (I would later see for myself that he was actually extremely good at pipe work). I didn't want to compound our situation by adding hot water problems, but I had no alternative solution. Then the owner joined us and told the engineer to cut apart the old unit to remove it. The new TRANE handler was slightly smaller in size and he believed it would navigate past the plumbing without needing to cut it apart. Then he left for the day while the crew kept working.
They first removed the evaporator coils and carted them to the truck.
The blower was next (the only potentially reusable part I think), and then he began cutting the metal box apart with snips so it could fit past the plumbing. There were a lot of trips up and down the stairs. When it was over there was nothing left of the old unit but a blank wall and a few wires and pipes. There was no going back now.
They brought the new unit upstairs and began the process of installing it.
He did have to cut away some plumbing, but these were pipes dedicated to the water drainage in the A/C and had nothing to do with the hot water heater. As noon passed I took food orders from everyone and ran over to the local Subway to bring back lunch. Subway was packed! Even with 4 workers the line was about 10 people deep. It took a while for me to get out of there and back home. At about 1pm everyone took a break to eat.
Saturday AfternoonAfter lunch they went back to work. I checked on our cat Lily; she was sleeping under the bed due to all the scary noises and voices. The upstairs temperature was now 85 degrees so I stayed downstairs with Cindy. A bit later I heard what sounded like steam hissing from upstairs. They had begun soldering the coolant pipes with a welding torch. This also produced strong odors of gas and ozone, which I'm sure confused Lily even more.
Hurdle #3 - Fumes
Within a few minutes, every smoke detector in the place was screaming. They are all connected and the fumes from his welding had set off the one near him. I quickly climbed a chair and disconnected the one near us then raced upstairs to find the engineer trying to rip the smoke detector above him out of the ceiling. He was standing on a ladder and apparently it was right next to his ear when it went off so he was a bit ticked. I became insistent and instructed him to remove it properly. When he did all the alarms stopped.
If you think we were pained by the screeching alarms, I'm sure Lily's sensitive ears took a worse beating. I went in to check on her and calm her down. She was so nervous that as soon as I entered the room she came out from under the bed and was extremely docile and wanting of attention. A short time later she was playful again.
Hurdle #4 - Fumes and Heat
With the crisis over he went back to using his torch, but within minutes all the alarms sounded again. The fumes had set off the next nearest detectors. We proceeded to remove the remaining detectors from the top floor. Then suddenly it struck me -- we also have sprinkler heads every 10 feet in this place, including one inside the very closet he's working on with a torch. Those sprinklers are sensitive to heat, and his torch is generating a massive amount of it. If they went off the water would damage the home, our possessions, and maybe summon the fire department.
At this point I ask them to do all the soldering they can in the garage and keep the rest to a minimum. I also set up some large fans to keep the hallway cooler and vented. I also had to check on Lily again and calm her down.
After about a half hour the repair crew emerged from the garage with the new handler and mounted it inside the closet. They spent the next 1-2 hours still using the torch to connect the system. The entire time I worried that the sprinklers would go off any moment. During this work they set off the alarms a third time, but they quickly quieted down and they continued working. I was greatly relieved when they were finally done with the torch.
It had now been several hours since the old hander was off, and Cindy and I noticed that our "colds" are much better. We didn't have colds - we had allergies from whatever the A/C system was spewing into the air, and it's removal was going to help with that as well.
Hurdle #5 - Time
It was after 3pm, and they still had quite a lot of work to do before they could leave. They cut and glued new PVC pipes for the humidity drainage from the handler, connected the main power and compressor wires, and connected the low voltage wires to the thermostat. By the time they were ready to turn the power back on and test the device it was near 5pm. Powered up, the blower ran at full speed and was not much quieter than before. We watched the temperature slowly drop from 85 down to 80.
We connected all the smoke detectors back up, put away all the tools, collected the trash, and vacuumed. I also let Lily out of her room and returned her food and litter box to their normal locations.
The final bill came to within $3.00 of the original certified check, so for that small a difference I could have avoided all the earlier running around to the banks and just gave them the original check.
We had every reason to believe the project was done, and I couldn't wait until the temperature dropped enough for the variable speed blower logic to get used and see how quiet it was. By 5:30 everything was done and the crew left for the day. The job was done, or so we thought.
When the temperature reached about 76 it was no longer blowing cold air, and the temperature rose back up to 84. The blower ran constantly, and the temperature never dropped lower than 80. Was it my programmable thermostat? Did they install the new handler wrong? Did all the coolant leak out? I changed the "smart" settings of thermostat off to see if that helped. No; it was still not cooling. It wasn't the thermostat.
Hurdle #6 - DIP Switches
After a light dinner out, I came back and began my investigation and learning about our new and old handler. I went outside and wrote down the model numbers for my compressor. I then read the handler's owner manual and went to the manufacturer's web site to read the documentation there. I learned a lot about the old and new units. One of the things I learned is that the new handler has a set of DIP switches for setting the air flow, compressor volume, and enabling the variable speed blower setting. I sat down for about 30 minutes and triple verified what I thought these switches should have as a setting. I went into the closet, pulled the circuit breaker, unscrewed the cover, and searched for the switches.
I found them after another 20 minutes. They were in the back and meant to be set while the unit was still unassembled. I had to get a flashlight and mirror to read them (upside down), and saw they were not correct. The flow was set to high, and the variable speed setting was off. Triple checking things, I changed them to what they should be and put the whole thing back together. I turned it on and volia, the blower started up on a slow speed and switched to high after 7 minutes - just like it was meant to! However it was still not blowing cold air and cooling the house down. I went outside and verified the compressor was running - it was. I turned off all the smart logic in the termostat - no impact. There was nothing more I could do.
I called the A/C people and left a message detailing the situation, and went to bed in an uncomfortably hot room again. The blower never shut off the entire time.
SundayI called them in the morning and we discussed the situation. The Owner was sure the handler was fine and problem was related to the compressor. His team would be at the house that afternoon.
Hurdle #7 - The Compressor
The same people came back that afternoon and began an examination of the outdoor system. Coolant level and pressure were fine, but when they checked the compressor they found that even though the fan was running the compressor was not. In fact it was hot. The reason was that the new handler was so efficient and modern that the 8 year old compressor was not getting sufficient current to kick it every time. They installed a small cylinder device that looked like a capacitor, whose function is to ensure there is enough current to kick the compressor on when the handler tells it to. This is similar to making sure your car battery has enough cranking amps to start the engine, even though it takes less amps to actually run the car.
Sure enough it worked. Cold air was blowing in the house and the temperature dropped to 74 degrees and stayed there! The new blower is much much quieter, and there are no leaks in the system. It is much quieter and has no leaks! It also looks much nicer in the closet. It came with a 5 year warranty and 1 year free maintenance. The A/C company now knows what to expect should they need to perform this work for another townhouse in my complex.
After almost a week and a half, we have a working and now quieter A/C system.
Syndicated 2008-08-05 13:39:12 (Updated 2008-08-07 03:04:02) from Keith
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