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Unloader help

July 14, 2015, 5:16 am
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I am working on a very old Jackson and Church 20 ton RTU. It has 3 unloaders sitting on the top of the compressor. We are currently experiencing near 100 degree ambients and this unit is tripping high head control. I have instructed the resident maintenance crew to clean the 2 condenser coils extensively which I am assuming they have done. These coils are close to 6" thick and require a lot of cleaning to make any difference.
Over the years this unit has been sliced and diced. It was originally a multizone, hot and cold deck. Now it is a straight cool or heat, minus the zones.
I realize the unloaders should be working on 1st or 2nd stage cooling calls. The original compressor I am pretty sure only had two unloaders, this one has three. Either way, I am thinking if I drop out one of the unloaders at times of high head I might be able to stop the manual trip control and if that is the best answer would I go about installing a auto reset psi controller with a adjustable time delay so it doesn't short cycle? any suggestions would be greatly appreciated. I will start with the cleaning and fan check out first, just getting armed before I make the journey. I know it is not overcharged. Thanks in advance!
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Dunham-Bush HXWC

July 14, 2015, 11:00 am
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Hey guys
Maybe any of you knows Technician and Factory password for Dunham-Bush HXWC. Controller is VISION 2020i (Carel touch screen)
Cheers
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Why Vapour traps are neccessary on PRV's

July 14, 2015, 11:41 am
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Hi Guys!
Just for Fun and Instruction.
The attached shows just how much water can accumulate in a s/steel Vent Line.
Making the pipework configuration critical. The standing water against the prv outlet has caused the seat to fail on 3 out of 4 prv's.
In fact the one you see is the remaining good one because the leaking by Ammonia in the others.
Resulted in no standing water left in them.
These pipes are led away from the Pac, up through the roof and along another adjoining roof for about 30 metres before they vent. (Less populated Area!)
Because of the poor (Site Fitted - Dairy!) pipe design and Install with huge amounts of s/steel pipe subjected to atmospheric conditions with no vapour trap. Huge amounts of Water have been produced within these pipes. All flowing backwards to the PRV's!!!

The Video only runs for 40 odd seconds, but I can assure you it was leaking and then shut off prior to taking the footage. It continued after stopping as well!

Something not seen to often but highly informative in my humble opinion.
Next time you see a red cross through a Danfoss diagram you will know why!
Grizzly

https://youtu.be/-0If3qLo1Ic

Thanks to my Colleague John for his input.
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Vacuum.

July 14, 2015, 1:45 pm
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I've been pulling a vacuum on a big VRV system which has been retrofitted . We reclaimed all the old R410 and fitted new indoor and outdoor units using existing pipe work. All Bs boxes and indoor units have flare fittings. I have been trying to pull a vacuum and am not sure if I've got a leak because I can't get it down past 20000micron. I've had the pump on for 8 hours. Because of all the oil polyester oil in the pipes could I be battling to get the vacuum? Or do I have a leak. It held 400 pasig for 12 hours.( nitrogen).
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KW usage

July 14, 2015, 8:16 pm
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The question came up recently about how much power my Fujitsu invertor actually uses. It's 4.8KW on heating but the thought was once it gets the room up to temperature does it begin to save electricity? So the thought was maybe the fan and the compressor can go into reduced power consumption modes. What can one expect? Thanks
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Toshiba Vrf Pressure Testing

July 15, 2015, 6:50 am
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Hi All

I have a small leak on a vrf system.
All the units are above the ceiling in a occupied very busy office.
I charged the system with 10 Bar Trace a gas and gone around with a suitable leak detector but no finds so far.
So I was thinking of upping the pressure for r410a
Say 35 bar to try and help locate the leak.
I'm not sure if this is true but I've been told under the pressure regulations I can only pressurise too 10 bar and not above with customers present
Is this True ?
Will it need to be done out of hours ?
Have really dealt with the pressure regulations before ?

Thanks Ian
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Toshiba AC P26 fault

July 15, 2015, 2:26 pm
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P26 Fault on a Toshiba system? We've had a call to look at a Toshiba AC that has a P26 fault. We haven't seen the equipment so can't give any model numbers. Done a bit of research and found that's its compressor related? Going there tomorrow so wanted to be armed with a bit of knowledge. Meter out the compressor for earth fault? We haven't done any work on Toshiba equipment, mostly Mitsubishi Electric and Fujitsu. Any advice would be much appreciated :0)
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30RB190 alarm FC.01

July 15, 2015, 6:46 pm
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Have a 30RB1905 with alarm FC.01 (need factory conf.) Reset the size on configuration but can't reset alarm , it will reject the reset, any help?
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No oil seen in glass in compressor

July 16, 2015, 9:33 am
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I recently checked out one of my thermo king reefers . the unit is sb-310 . Unit was running and I didn't see any oil in a sight glass in compressor. I heated it up for 30 min and after put on cool high speed and still nothing. When i shut down unit and restart and unit was running at a low rpm on cool I noticed there is some drops of oil hitting the sight glass and the oil was barely seen in the bottom of glass. After the unit switch back to high speed no oil was visible . Should I add oil to it?
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York chiller YAEP Micro Control system program - Reprogram type of refrigerant to run

July 16, 2015, 9:41 pm
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Hi,
I have the following problem. Kindly advise if anybody has expertize about the york systems.

Initially there was a power fluctuation, display went off, unit not running, try to reset but no use.
a) replaced the power board and display unit - problem not solved
b) replaced processor board with old eprom -same
c) revert the old board but replaced the battery from new board, keep the power ON for some hours.

Got the display back...but

I find factory settings require reprogramming. "Reprogram type of refrigerant to run"
when I try to enter through Keypad- 22 for R22, there is no response.

How I can reprogram the factory settings and what is the code for program?
controller - YAEP Micro based control system
unit - YAEP99WD9C50PA, China

pl suggest, thanks in advance.
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Melco SUZ-KA50VA2.TH crankcase heater

July 17, 2015, 1:51 pm
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Hi all.
Can somebody tell me - is this unit have built in crankcase heater or not? Like some other inverter units use winding's to heat up the compressor in standby mode.
Appreciate for any information.
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Technoblock, or techno*ock as some call them

July 17, 2015, 2:25 pm
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Techno Block, or Techno dung as it is called. (it rhymes better in Norwegian :))
An apprentice had been on the site and changed the DIXELL brain on the unit.
I came to help with setting up the new device since they didn't provide a proper settings list when it was delivered, or when we requested one.

Set it up and started plant. the on site engineer asked, "When will you mount the missing fan?" We did not know anything about a fan who was removed, called around to all installers who had been there, no one had removed any fan, went into the freezer, and yeah it lacked a fan at one evaporator and from ground level it seemed like the cable was isolated. The plant had run for about 20 minutes and the temperature was falling, was still talking to the engineer when I noticed a new sound, which I thought was from the production facility (I'm deaf in one ear :)) engineer asked if the sound was normal. I said that perhaps it was ice that had fallen into the fans from the ceiling (because both evaporators were ice-free, checked before I started it), stopped the plant and went into the freezer, no ice on any of the evaporators, heard a noise that sounded like ice on a hot element, got the engineer to start the system again so I could watch the fans while they were running, didn't see anything wrong, but it sounded like mayhem.
Got a ladder and climbed up, And it turned out that the missing fan had fallen inside (the four bolts that hold the motor to the grate had sheared off) and had done the heebiejeebies inside, and what I initially thought was water boiling on a heating element turned out to be a leak in the evaporator after the fan had finally broken it's blades off and gone bananas...

Closed the liquid valve and left the apprentice there to pump down the system as I rushed back to the workshop to pick up the acetylene-oxygene kit and some silver solder.

The customer had somewhere around $275.000 worth of king crab in there and when I told him it was leaking he asked if he should order a truck to move his goods to a freezing storage, I told him to give me 90 minutes before he made the call, from that time it took me 129 minutes to get the gear, gut the pipe to the bad evaporator, solder it shut and get the system running again...


I hate working on copper pipe systems :)
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i need to diagnostic software

July 18, 2015, 9:14 am
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Compressor is crash

July 18, 2015, 12:38 pm
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Compressor is crash ...... what are the ways of cleaning the circuit of oil, aluminum and iron filings.
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Dunham Bush Chiller

July 19, 2015, 2:58 am
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Hi Everyone
I have a 30 year old Dunham Bush chiller which I am nursing along, but due to the age of the unit there is no wiring diagrams available.

If someone has any information for : Dunham Bush OPCA 200 Air Cooled Chiller that would be great.

The Chiller is made up of 2 separate sections bolted together so maybe a wiring diagram for a OPCA 100 may also be useful.

thanks Bobjob
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Residental split R22 - 1T All Style Coil Co. evap. with piston to 3T york condenser.

July 19, 2015, 6:31 pm
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:confused:
Hi guys, I arrived to to this unmatched unit which had 100psi on LS and 200psi on HS at 103F ODB :eek:. Couldn't do any adjustments since it wasn't responding. Found empty fitting where suppose to be the piston and didn’t have even the nylon seal so it was leaking a bit. During hot days the tenant claimed to be able cool his 15 years old 1412SF home with 10' tall ceiling in the center to about 77F but running all-day long and in the evening til morning or on cloudy days it was cycling properly even with missing piston.
Installed .074 chatleff piston with triple evacuation, brazed in missing filter/dryer and got the pressures finally to act. Charged by superheat with additional 2Lb of freon due to 24' LS pipe and perhaps the oversized 4T coil to 3T condenser, Factory charge for the york condenser is 5Lb 3oz.
I read on york site that if over-sizing 1T like in my case, it should still have piston matched for the condenser. Superheat was fluctuating 8F from 53F-61F at 12amps draw of 15RLA so I am not sure if I should try to put a bit of freon. I know on cars if the freon is low but still able to trigger the pressure switch it will cycle due to the freon pushed till switch goes off and then pressure rises till switch goes on.
I forgot to watch pressure for rise and fall which could indicate similar matter but each time I looked :rolleyes: at gage it was 80psi. Perhaps with that amount of freon it won't show but internally it may be missing at certain point some freon? I'll call them tomorrow to see the performance during the day.
I was there twice due to not availability of the piston,
Readings: (Arizona :cool:)
WB - 64F
ODB - 96
LS - 80psi
HS - 240psi
Temp. in handler - 77F
Temp. out handler - 54F
Thanks everyone for looking.
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York YAEP chiller problem- power failure alarm

July 19, 2015, 8:29 pm
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Hi,
I have the problem still not identified. Could someone please tell me how to solve it.
Chiller- ambient air cooled 2 circuit York YAEP, China

Chiller is stopping immediately after starting the circuit. either 1 or 2. Alarm is also not the same every time. Changed the power board, processor board, relay board. All the fuses are checked ok.

alarm - power failure manual reset
or unit 1/0 switch in off condition.
and sometimes display goes out along with the above fault.

Suspecting there is some field side common circuit is dropping the voltage but where to check? What are the check points on the processor board
Anyone please guide

Thanks
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about Thermo King SB-210 board light

July 19, 2015, 11:47 pm
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Hello everyone
I have a question of TK SB-210
the operating board can't light on
does anyone who was ever replace the board light LED ?
and please tell me how to do, thanks

I apologize for my english is very poor
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How to determine the correct air over an evaporator coil

July 20, 2015, 6:16 am
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Hi everyone,
I work for a small custom Display Case Mfr. Last week, we had an issue in the field with too much air overloading a unit and it has me thinking that in some instances, fan choice may have been just a guess based on a previous design. Simply put, an educated guess. We haven’t made that particular sized case since 2010 so I don’t have recent history to refer to.

In determining the proper airflow over the evaporator is there a way to come up with the best fan choices? When I was in in the field as a service tech I would look for a 10°f differential across the coil and call it a day.

I realize that airflow is probably the most complex issue in a display case especially open type air-curtains. However I believe this site has the brightest minds around and I just may find some little thing that leads to learning something new. (and I'm not just blowing smoke)

As always thanks for your input.
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1933 Monitor Top restoration + compressor pics

July 20, 2015, 10:37 am
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Hi Guys,
I posted questions about this compressor a few years ago and finally finished the unit and put it into use.

Here's a quick video of the restoration as well as a decent recording of what it sounds like running. Microphone was about a foot or less from the compressor. In person you almost can't tell when it's running. When I was timing it's cycles I had to get up and stand right next to it to make sure it was still on a few times.

https://youtu.be/y2LWjT3e7uQ



Here's a link to what it's oscillating type compressor looks like. This isn't one of mine as none of mine have been opened, but is an identical model that a friend cut open as it was seized and couldn't be broke loose electrically.

https://plus.google.com/photos/10115...CLeA7Y_ZqZS8MA


Here's a short video he filmed of it running after he got things moving.

https://youtu.be/bfkNLHy9nkw

And finally, a video of him turning it by hand to show how it pumps.

https://youtu.be/gn0u7dFBCTk


The machine is mostly original except I installed a capillary tube to replace the badly worn float valve and I replaced most of the wiring. Everything else was cosmetic. It's currently maintaining around a 31-32F cabinet temp which is perfect for me.
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