I'm in need of some professional assistance regarding the diagnosis of an HVAC system.
As a bit of a back story, I installed a new furnace & condensing unit in my home about 10 years ago. I didn't have central air, but figured I'd put the condensing unit in for an HVAC install at a later date. The condensing unit states it's good for both R22 & 410 systems. At this time (10 years ago) the line set was run to the exterior, however it was not connected to the condensing unit. The condensing unit had factory plastic plugs at the open ends, and the line set had tape covering each end.
3 years ago, I received a 4-5 year old air conditioner that was pulled by an HVAC tech on a demo project. The unit was clean and didn't show many signs of aging. This year, I finally got around to running 220 to the exterior, installed a disconnect, and wired up the air conditioner. I ran low voltage control wiring for the contactor and hooke up everything on the furnace/thermostat. All electrical systems were tested and working, including momentarily bumping the compressor/fan to ensure operation.
The AC unit is an R22 system, and I received a quote from an HVAC contractor for $ to hook the lines up and charge the system. The gentleman who arrived took 8 hours to solder the lines to the ac unit and condensor (that's no joke). Afterwards, he hooked his gauges and tank of R22 to the AC unit. While he was outside, I heard a hissing sound coming from the condensing unit. There was (presumably) a compression fitting at the low side line coming out of the condensing unit that was never tightened. I immediately brought this to his attention, and he stated that he performed a vaccuum test and leak test, and was unsure how that was not caught. The compression fitting was tightened and he resumed working on the system. 20 minutes later, he stated that there was a blockage in the system. He stated with certainty that either the line set or the condensing unit had a blockage. He brought me outside to show me that the (blue) vapor low side had a pressure of 0 while the compressor was running. He stated that it was up at one point, but dropped to zero. Unfortunately, I did not observe the gauge reading on the high side (red - liquid). I am unsure if he was trying to charge from the low or high side. I am unsure of the state of the valves on his gauges. On a phone call with his boss, I was told that they would need to replace the line set at $\. I immediatly had them cease working on the system and have not paid them.
I'm no HVAC technician, which is why I had a (real?) contractor come in to do this work, and why I'm seeking help on this forum. However, there's a few things I am certain of. First, a 10' line set shouldn't cost $\. Second, 8 solder joints shouldn't take 8 hours. Third, nothing special was done after the leak was found; however, I'm uncertain if there's a protocol (nitrogen flush?) to follow after finding a leak. Based on what I've observed, I can say for certain that the air dryer was not replaced.
Had I been more astute, I would have closely monitored his work for deficiencies. However, at a 9 hour visit, and having trusted a professional to do a "professional" job, I didn't want to stand over the tech's shoulders. As a result, there are a few things that I am uncertain of: I have no idea if the line set was tested (put your mouth and blow on it) prior to soldering. I did not observe any tanks of nitrgen and are unsure if any air was purged from the system. I am unsure how much R22 leaked out of the system into my house (unless it was at a vaccum, in which case maybe air was pulled into the system?)
After some reading, my gut is that perhaps the air dryer is clogged, but again, I'm no expert. So my questions are this:
As a bit of a back story, I installed a new furnace & condensing unit in my home about 10 years ago. I didn't have central air, but figured I'd put the condensing unit in for an HVAC install at a later date. The condensing unit states it's good for both R22 & 410 systems. At this time (10 years ago) the line set was run to the exterior, however it was not connected to the condensing unit. The condensing unit had factory plastic plugs at the open ends, and the line set had tape covering each end.
3 years ago, I received a 4-5 year old air conditioner that was pulled by an HVAC tech on a demo project. The unit was clean and didn't show many signs of aging. This year, I finally got around to running 220 to the exterior, installed a disconnect, and wired up the air conditioner. I ran low voltage control wiring for the contactor and hooke up everything on the furnace/thermostat. All electrical systems were tested and working, including momentarily bumping the compressor/fan to ensure operation.
The AC unit is an R22 system, and I received a quote from an HVAC contractor for $ to hook the lines up and charge the system. The gentleman who arrived took 8 hours to solder the lines to the ac unit and condensor (that's no joke). Afterwards, he hooked his gauges and tank of R22 to the AC unit. While he was outside, I heard a hissing sound coming from the condensing unit. There was (presumably) a compression fitting at the low side line coming out of the condensing unit that was never tightened. I immediately brought this to his attention, and he stated that he performed a vaccuum test and leak test, and was unsure how that was not caught. The compression fitting was tightened and he resumed working on the system. 20 minutes later, he stated that there was a blockage in the system. He stated with certainty that either the line set or the condensing unit had a blockage. He brought me outside to show me that the (blue) vapor low side had a pressure of 0 while the compressor was running. He stated that it was up at one point, but dropped to zero. Unfortunately, I did not observe the gauge reading on the high side (red - liquid). I am unsure if he was trying to charge from the low or high side. I am unsure of the state of the valves on his gauges. On a phone call with his boss, I was told that they would need to replace the line set at $\. I immediatly had them cease working on the system and have not paid them.
I'm no HVAC technician, which is why I had a (real?) contractor come in to do this work, and why I'm seeking help on this forum. However, there's a few things I am certain of. First, a 10' line set shouldn't cost $\. Second, 8 solder joints shouldn't take 8 hours. Third, nothing special was done after the leak was found; however, I'm uncertain if there's a protocol (nitrogen flush?) to follow after finding a leak. Based on what I've observed, I can say for certain that the air dryer was not replaced.
Had I been more astute, I would have closely monitored his work for deficiencies. However, at a 9 hour visit, and having trusted a professional to do a "professional" job, I didn't want to stand over the tech's shoulders. As a result, there are a few things that I am uncertain of: I have no idea if the line set was tested (put your mouth and blow on it) prior to soldering. I did not observe any tanks of nitrgen and are unsure if any air was purged from the system. I am unsure how much R22 leaked out of the system into my house (unless it was at a vaccum, in which case maybe air was pulled into the system?)
After some reading, my gut is that perhaps the air dryer is clogged, but again, I'm no expert. So my questions are this:
- Is it unreasonable to expect an HVAC company to test continuity through existing lines before hooking up a line set?
- Would it not be normal practice to change an air dryer on a system that has been exposed to ambient air for years?
- Should I let this contractor attempt to "make it right" on a future visit?
- What should I expect for a proper dianosis of a system in this condition?
- Am I wrong in not having paid the contractor any amount of money on this visit?
source https://hvac-talk.com/vbb/threads/2239248-Contractor-stating-HVAC-coolant-lines-are-blocked?goto=newpost
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