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bernard
30-04-2005, 08:01 PM
Hi all

Scroll compressors no brazing easy to change!!!!!

Any one got any tips for getting the sight glass off apart from heating it.

Regards bernard

bernard
30-04-2005, 08:26 PM
Hi

The king can take a pawn and no one will notice,a pawn can take the king and every one will notice.

Even the mighty fall sometimes never under estimate the pawn. ;)

Regards Bernard

Peter_1
30-04-2005, 09:00 PM
[QUOTE=bernard].. Scroll compressors no brazing easy to change!!!!! Any one got any tips for getting the sight glass off apart from heating it.
QUOTE]
English is not my mother-tongue but what do you mean with your 1st sentence? No brazing? Easy to change?
Which sight-glass, oil sight glass on compressor, liquid sight glass?

bernard
30-04-2005, 09:26 PM
Hi peter


Sorry I ment the oil sight glass,Its put in with some thread lock,if you put to much pressure on it,it shatters the glass.Was just enquiring if anyone had other techniques for removing it.

regards bernard

bernard
01-05-2005, 09:09 AM
Thanks will try that I guess its around 30mm.

The king rarely moves and relies on the pieces around him for his strength but is there at the end.

A pawn moves and is normally sacrificed,but has lived life at the sharp end.

Regards Bernard

chemi-cool
01-05-2005, 03:48 PM
Hi Bernard,

I'm a bit puzzled,
Why do you want to take the sight glass off?? :confused:

Chemi :)

chillyhamster
01-05-2005, 03:58 PM
3rd party oil management systems require the bulls eye to be replaced with a hall effect sensor housing / adaptor plate. Thats why.

Leave the rubber bungs in the discharge and suction. Lay the compressor on its side with sight glass upper most. Use a socket with an extension to undo, carefully as there should be a slight ofn pressure. Fit replacement oil management system, stand compressor upright and fit as mormal.

chemi-cool
01-05-2005, 06:25 PM
Thanks,
I'm surprised, the manufacturers did not prepared a connection for it.

On the semi hermetic its ready for it and on Maneurop.

Well, not a dull moment.

Chemi :)

bernard
01-05-2005, 07:55 PM
Hi

What problems would occur if a liquid injection system on a scroll was permanently injecting.

Thanks bernard

frank
01-05-2005, 09:15 PM
What problems would occur if a liquid injection system on a scroll was permanently injecting.

You would end up losing the compressor. Liquid injection is used for compressor cooling primarily, although it can be used for other reasons such as pressure equalisation. If the compressor is not hot enough to vapourise the liquid as it is injected then you can end up with liquid slugging and a loss of lubrication leading to premature failure.

chillyhamster
01-05-2005, 09:53 PM
Hi

What problems would occur if a liquid injection system on a scroll was permanently injecting.

Thanks bernard
If the compressor was in a stationary condition the crankcase would fill with liquid. This would cause oil dilution on start up and possible long term damage. If the compressor is running then there are two types of liquid injection, a) the external pot which requires braizing, this contains a capillerie tube. b) is a thermostatically controled inlet valve which would shut off when the discharge is cool enough. Neither would experince problems if over cooling during run cycle.

Dan
04-05-2005, 02:38 AM
What problems would occur if a liquid injection system on a scroll was permanently injecting.

Interesting you should ask, Bernard. We have a situation with parallel compressors where a former factory field service engineer and others decided that medium temperature liquid injection with R22 was actually causing liquid carryover into the separator, thus recycling unevaporated liquid with diluted oil - so the injectors were removed. Now, we are being asked to re-instate them. This situation differs from what you describe as "permanently injecting." However, the normal setup for these injectors is to inject regardless of discharge temperature, and always when the compressor is running. If injecting when the compressor is not running, Chillyhamster put the likely outcome in fair words.

The injectors I am being asked to reinstate are the canisters that have the capillary tube wound up in them, operated by a solenoid in parallel with the compressor contactor. Chillyhamster, is there another Copeland approved method of liquid injection? You mention a thermostatically controlled device?

chillyhamster
04-05-2005, 05:49 PM
Hi Dan, DTC can only be fitted to scroll comp designed for it ( hole in top center, covered with plastic plug) where temp sensor is fitted. Unit is attached to the same injection port as the cap can. cap can can be fitted in lou of the DTC. seems like i have been to the moulin rouge with all these can cans.