Hi to all members of this interesting forum. I'm new member here and I find it very resourceful since I'm also DIY guy. But I have a question for experts here regarding something different.
I'm not familiar with technical english regarding air conditioners but I'll do my best to explain situation. There was one air conditioner which was 1 year out of order. Service crew came, put pressure gauge to measure pressure - it was 15 bar(215 psi) (allegedly normal pressure in idle position). Then they turned on air conditioner, everything looked fine, no strange noises, nothing unusual.
Few minutes later pressure fell to 8 bar(115 psi) and after that, without any warning, huge explosion in compressor area. Part of compressor was found 70 meters away. There was also fire from compressor oil and complete pipeline went missing - it blew it away. Service crew were injured but all survived. Before the explosion one of the crew noticed loose valves which indicated him that someone else was trying to repair the air conditioner before.
Loose valves were impossible if device was left untouched for 4-5 months in city area near the sea. He is guessing that someone was trying to repair air conditioner, first by pumping nitrogen into the system and left it there for months. If that's the case, why explosion few minutes after turning the device on?
I would suspect shortcut if compressor blew immediately after turning on, but he exploded minutes later, after working without any suspicious behaviour. What do you think happened?
There were evidence of tampering with device but no one can't explain why explosion minutes after turning on.
My best guess is that if extra nitrogen was in, it was burdening the system and when compressor started to put more pressure, system reached pressure maximum and exploded. But why was valve reading pressure falling and not increasing if that's the case?
Any ideas?
Last edited by PJmax; 02-17-22 at 06:52 PM.
Reason: added psi values
At "idle" or rest...... the high and low pressure will measure the same. 215 psi is not a normal resting pressure. The normal resting pressure is around 100 psi. That is based on type of refrigerant and temperature.
It appears it was severely overcharged. When it started.... the pressure went sky high.
Yes, it was R410A inside. And my info is that 200 psi is normal pressure for that kind of system. But why was compressor overcharged? What could possibly overcharged it? Keep in mind that it was found out that someone tampered on the system before service crew came. Can in be because of extra gas inside?
It wasn't mine A/C
My friend was working in the company where one of them got hurt in that accident.
We guessed it's probably nitrogen from illegal repair attempt few months ago.
Thanks, I appreciate it.
The techs should have had a dual gauge setup connected. Based on your original pressures...... 215 psi and down to 115 psi when running would indicate the low side of the system. If the low side was running at 115 psi...... the high side could have been up to 500 psi or over. They should have seen the high side excessively high.
I received 2 estimates for air conditioning work on McQuay HSE-060AR 6000 cfm chilled water unit in one bedroom 750 square feet condo. This is in HCOL area Honolulu. One quote was for 10000 to replace this AC with new unit therefore thats out of my range. Does 1500 dollars or 2100 (additional 900 if fan replaced) sound right for such cleaning job?
1st ESTIMATE $1525
Removal of cooling coil/fan assembly for chemical cleaning and flushing
Replacement of old fiberglass insulation with new Reflectex insulation
Reinstall cooling coil/fan assembly purge cooling coil of air
Replace old wall mount thermostat controller with new Honeywell digital controller
Restart system and confirm proper operation
2nd ESTIMATE Total $3000
Removing, cleaning and replacing the coil 600.00.
Replacing the insulation with new rebate or Armaflex 1 inch insulation....900.00.
Installing a new digital thermostat 600.00
New motor and fan wheel 900.00Read More
Our outside unit, a Trane Xl16i, [color=#333333]4TTX6036B1000AA stopped working a few days ago. I believe I have narrowed it down to the the LPCO. I can see the 24V measures across the blue/yellow that are coming from the control board of the blower/furnace. I do not see 24V at the contactor/coil. It looks like the HPCO (Yellow/Black) is working as I can see the 24V from when measuring the blue from the control board and the Black side of the HPCO. I am not seeing the same though for the LPCO, as I do not see 24V across the yellow from the control board and the contactor blue wire that comes from the LPCO. Could something else be pulling the voltage down or is this definitely an LPCO issue? If I engage the contactor manually I do hear the compressor start but not that fan. The schematic seems to show that blue going to the fan so that would make sense. Could it be the fan is bad and it is causing the blue to ground or such? I assume replacing the LPCO means I need someone with pressure gauges, refrigerant? As a test could I by pass the LPCO with a jumper and see if that momentarily bring the system online or is that a risk?
Thank you,
Keith[/color]Read More
02-17-22, 12:56 AM
