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HAROON
12-09-2006, 11:28 AM
HI, I AM WORKING IN COLD STORE WITH R22 AS REFREGERENT. I WANT TO KNOW THE EXACT METHOD TO VACCUM THE SYTEM, IS IT NECCESSARY TO CHANGE DRIER FILTER AND SUCTION FILTER ,WHEN TO CHANGE( BEFORE OR AFTER VACCUM). HOW TO PERFORM SELF VACCUM USING COMPRESSOR ,IS IT GOOD.:rolleyes:

IAM NEW TO THIS FIELD

REGARDS
Peter_1
12-09-2006, 12:47 PM
Pumping vacuum with the compressor is not a good practice: compressor can't achieve a low enough vacuum .
Compressor may not run for a loner time in vacuum, windings aren't cooled with a suction gas cooled machine.

For the price of a dryer, I shouldn't hesitate to replace it.

I vacuum a suspected wet system first with the old dryers in place, heat them up till +/- 70 to 100 °C with a heat gun.
Then brake the vacuum with nitrogen.
Change filters and vacuum again with the new dryers in place.
HAROON
12-09-2006, 04:59 PM
heat them up till +/- 70 to 100 °C with a heat gun.
HOW TO PERFORM THIS TASK.
REGARDS
Peter_1
12-09-2006, 06:30 PM
http://www.diydata.com/tool/heat_gun/heatgun.jpg
HAROON
13-09-2006, 12:22 PM
ok thanks peter

regrds
jinxycat
13-10-2006, 08:48 AM
LOL, a picture paints a thousand words
taz24
13-10-2006, 06:09 PM
Why do you need to vac the system? Do you have moisture in the system? Changing the driers is a wise precauton. Two methods to vac that work.

1. Deep vac. Put vac on and leave for 24 hours or so
1. Tripple vac. vac then brake with OFN, second vac and brake with OFN and finaly vac and charge with gas. Each vac getting increasingly deeper aiming for a 2 torr or less vac.

Cheers taz.
Peter_1
13-10-2006, 07:02 PM
Taz24, I do it almost the same way you do, except that I don't let it run that long.
For a new setup till +/- 10 HP and 'normal' length of copper, each cycle lasts +/- 1 hour and braking the vacuum each time with OFN.
Sometimes running with 2 pumps as far as possible from each other. All SV's energised with a permanent magnet.
taz24
13-10-2006, 08:00 PM
2 pumps as far as possible from each other. All SV's energised with a permanent magnet.[/quote]


Yes I agree Peter. The little coil pullers are a god send when vaving and pressure testing:D If the system will permit then I fit the vac on one side of the system and the torr gauge as far away as possible to get the true reading.

Cheers taz.