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mtremblay
15-03-2014, 08:52 PM
When replacing a compressor on a heat recovery Daikin VRV 3 condensing unit (REYQ120PATJ) is it considered acceptable procedure to isolate the condensing unit, recover refrigerant and carry out the repair? I'm thinking if I place it in Recovery Mode, front seat the 3 service valves and pull from the charging port (I would have to add an additional pressure tap to permit nitrogen purging) I should be fine instead of pulling the entire charge and p-test/evacuating the entire system.

Also, I have a Daikin technical bulletin that seems to state that burnouts require refrigerant replacement and the addition of a suction drier. What about a non-acidic compressor short to ground? Technically the windings failed so some level of contamination could exist, but if an oil test confirms insignificant acid levels I would suspect these measures would be unnecessary.

install monkey
15-03-2014, 09:07 PM
your supposed to change the oil in the other compressors- best to pull out all the gas to comfirm the charge is correct and prevent possibilities of valves weeping causing nitro to enter the parts of the system you didnt reclaim from

mtremblay
15-03-2014, 11:36 PM
Thanks install monkey. Is the oil change only for true acid burnouts or a failed compressor of any kind?

install monkey
15-03-2014, 11:43 PM
mainly burn outs- daikin do a kit thats about 150 quid- you get an oil can .6ltr of oil and a chunk of plastercine- and a plastic hose- the idea is you pull a vac on the can and cyphon the oil out the sumps with the clear tube and seal the hole in the can with the plasercine

RusBuka
16-03-2014, 06:16 AM
How long work outdoor unit with 1 burned compressor?

VRVIII
16-03-2014, 08:57 AM
mainly burn outs- daikin do a kit thats about 150 quid- you get an oil can .6ltr of oil and a chunk of plastercine- and a plastic hose- the idea is you pull a vac on the can and cyphon the oil out the sumps with the clear tube and seal the hole in the can with the plasercine

Oil Replacement in the other compressor & the oil kit is only applicable for G series R22 VRV units (reciprocating compressors with 3GSD mineral oil)

VRVIII use scroll compressors containing ether oil, remember to use an acid test kit which is compatible with ether oil and to obtain the oil sample from the piping or good compressor (not from the faulty compressor). It is unusual to have high acid levels on a VRV3 systems.

RusBuka
16-03-2014, 09:49 AM
Often compressors burn out if works with high discharge temperature, and PVE oil have interesting colors.
My friend washes system of burnt oil and after combustion compressors without unpiping system.
http://onsyi.ru/index.php?option=com_content&view=article&id=117:2014-02-28-18-16-02&catid=54:moika&Itemid=88

mtremblay
16-03-2014, 08:11 PM
Its been about 2 weeks of operation with one failed compressor.


How long work outdoor unit with 1 burned compressor?

mtremblay
16-03-2014, 08:19 PM
Oil Replacement in the other compressor & the oil kit is only applicable for G series R22 VRV units (reciprocating compressors with 3GSD mineral oil)

VRVIII use scroll compressors containing ether oil, remember to use an acid test kit which is compatible with ether oil and to obtain the oil sample from the piping or good compressor (not from the faulty compressor). It is unusual to have high acid levels on a VRV3 systems.

What brand of acid test kit are you using? Of the common acid test kits available in Canada (Carrier Totaltest, Nu Calgon, Sporlan, Checkmate, Quik-Check) none of them appear usable with PVE oil except the Quik-Check which is a simple Litmus paper.

Do you agree that it's advisable to recover the entire charge versus isolating the condensing unit for the compressor replacement? There is roughly 60lbs (27kg) of refrigerant.

hyperion
17-03-2014, 07:27 AM
If you do not recover all of the gas, then there is a chance of bleed over of OFN via the shut off valves when you carry out your high pressure test.
Better to be safe, than create an awful lot more work that you won't get paid for when you find that the operating pressures are not correct.

mtremblay
18-03-2014, 02:42 AM
Thanks for the responses guys. Much appreciated!

mtremblay
18-03-2014, 02:51 AM
Often compressors burn out if works with high discharge temperature, and PVE oil have interesting colors.
My friend washes system of burnt oil and after combustion compressors without unpiping system.
http://onsyi.ru/index.php?option=com_content&view=article&id=117:2014-02-28-18-16-02&catid=54:moika&Itemid=88

I pulled the failed compressor today and took an oil sample. The color was grey, similar to one of the pictures/videos in the link you posted. I'm thinking either its carbon from the burnt windings or possibly carbon deposits from the installing contractor not using nitrogen while brazing.

This appears to be the 2nd compressor failure in this VRV 3 unit since it was installed. It's also located 14 floors above the floor where the indoor units are located. I've determined there is an upgrade PCB board that can enable operation of up to 90m height difference, but I need to confirm if that board is in fact installed as we're above the 50m max with that standard board.

RusBuka
19-03-2014, 01:01 PM
Grey colour is working with liquid in suction line. Cut comressor and take a look on spirals.

Onsyi
19-03-2014, 03:16 PM
What brand of acid test kit are you using?
If you fill out this test (If you fill out this test to cover the test show acidity, if it is. In general, use pH-meter.) to cover the test show acidity, if it is. In general, use pH-meter.

Onsyi
19-03-2014, 03:18 PM
If this test is to fill it to the top....
Do not know the language - it's sad.

RusBuka
19-03-2014, 03:54 PM
Danila hi)

Onsyi
19-03-2014, 06:06 PM
Привет, привет! :)
noticed a sharp spike of visits to the site from the United States, it was interesting - who?

Onsyi
19-03-2014, 06:09 PM
http://www.holodps.ru/catalog.html?page=shop.product_details&flypage=flypage-ask.tpl&product_id=332&category_id=3

I ask to forgive any wrong link above, link to dubriruyu acidity tests.