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Coolie
14-10-2004, 05:41 PM
I found the strangest thing today, I was doing a routine maintenance on a chilled water system and while checking the drain on one of the fan coil units I notice a block!
Upon Investigating, I found that at the outlet of the drip tray there was no hole and by the looks of things, never was! Now even stranger is that the unit has been in operation since day one, about five years ago!!
Nobody has noticed this before, and it has never been reported as having a water leak!


I wonder what I'll find next....a split system that has not been piped up and the client never knew> You laugh, I have seen this and the owner was none the wiser.
Talk about cowboys

Whats the funniest/ strangest find you've made!

Gary
14-10-2004, 07:23 PM
I once worked on a rooftop A/C unit, with three parallel cap tubes. One of the cap tubes had been brazed shut at the factory. Someone had added extra refrigerant to raise the suction pressure, which kept the coil from freezing. The head pressure was extremely high.

This unit had undergone quarterly inspections, by a wide variety of service techs, for 18 years, with nobody noticing the problem.

rbartlett
14-10-2004, 08:24 PM
two jobs

1 a split had been installed and running for about 3 years but had no gas

an inspection by us with OFN found above the ceiling the last 2 foot of liq line missing!!!


2 a condor 10 ton 'split' (ie the evap on top of the condenser) cooling an important documents/records storehold installed several years

these come with the factory connectors which when tightened pierce the disc to allow refrigerant flow- I think they were called areoquip connectors ??

anyway sadly the suction one wasn't ruptured and thus the unit wouldn't run.. the contractor who I was subbing to (and who installed it btw) just said 'heyho just don't tell anyone'!

Dan
15-10-2004, 01:27 AM
In the supermarket trade, I have come across at least 5 vertical air discharge condensers piped backwards that have been in operation for more than a year. One, for at least 5 years.

My all time favorite was a liquid feed nightmare, that went on for months. After we started piecing the pieces together we disassembled the liquid header and found the quality control checklist, or what was left of it. It was signed off as approved!

Brian_UK
15-10-2004, 02:52 PM
I once had a small Mitsi that had run for 18 months that only had the process tube on the compressor sealed with a plastic cap..... it finally melted !

Blueboy
15-10-2004, 09:37 PM
I have a couple

The first was a split I installed on the side of a building. I was called back to site after a neighbour contacted the environmental health officer about a noise pollution problem. A meeting was arranged for all parties to discuss the problem that was causing wakeful nights due to air-conditioning noise. It was at the meeting that I mentioned we need to do a building power down to fit the MCB and the unit had not actually been running yet!

The second was a cold room in a very large Threshers AMPM mini market. We had a lot of problems with the room not holding temp so we replaced the condensing unit and the evap and the controls. It ran fine for two weeks then we got another call out. On arrival at site I discovered that someone stolen the inter-connecting pipe work and the three phase cable while it was running!

frank
17-10-2004, 03:14 PM
http://www.refrigeration-engineer.com/forums/showpost.php?p=7402&postcount=4

stan1488
17-10-2004, 04:28 PM
brings to mind a job we went to start up pushing it late into a friday ,customer etc , ***** lg walk in , over a 100` of 1 1/8" liquid , installers daydreaming , left the endcaps in the tube, twice!! lot of joints , fun night!! :cool: regards

Coolie
10-11-2004, 05:52 PM
Here's another for the record.....

I was sent to a job where a subbie replaced a compressor on a Hitachi twin split sytem.(the details of the units escape me). I had to replace the contacter for the comp as it had welded closed and the breaker had tripped and would not reset, then add the remaining refrigerant(400g) that he could not get into the system as it would not run.
Nice easy job, or so I thought....
After replacing the contacter, I reset the breaker turned the isolater back on and set the system to the cooling mode. Everything was running to plan until the comp kicked in. The breaker tripped and would not reset, strange! Checked the rating of the breaker and found it to be acceptable. Went back to the roof to check the contacter which I found to be welded close again?!? What was going on I thought. I started going throught the system with multi meter in hand and thoughts running through my mind like wild fire!!! Checked the isolater and found continuity between red and yellow phases. Disconnected the power supply to compressor and checked isolater again, wheyhey no continuity, naturally I think I found the culprit, dodgy contacter!
Well to cut a longer story short I spoke with Hitachi's technical guy and after doing a few checks I found the compressor that was replaced had been replaced with a single phase unit and not a three phase one. The model numbers all coincided and what I think has happened is that the wrong id plate was stuck to that particular comp stating that it was 3 phase.
Basically the red and yellow phase were shorted through the Common to run windings causing the breaker to trip, but not before the new contacter managed to weld itself shut.

Coolie
29-11-2004, 06:49 PM
Got sent on an emergency call to a new residential apartment block. Two out of the four Daikin VRV systems were showing a U4 fault code(transmission error between outdoor and indoor/bsv box).
I discovered that the electrician/cowboy had not earth bonded the isolators to regulations. The idiot took the earth through the TOP of the isolators and did not use any form of gland. Sure there was a rubber grommet, but the result was that when it rained water would run down the earth cable and into the isolator. The problem got so bad that two out of the four circuit breakers tripped out.
We have only just picked this contract up as it is a new install, but what kind of a person works like this. And as for the commissioning engineer, what the hell was he doing not to pick up on this.