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wilks
27-11-2007, 10:29 PM
hi guys just wanted to ask a question , changed an automatic lp switch ( for pump down ) and set the range at 30psi an diff at 25 psi , thats what ive allways done for gas of r22 ,then my work buddy said that the range should be higher ? what do you guys think?? thanks alan:confused:

get the gauges
27-11-2007, 10:52 PM
sounds ok ,in fact on freezers you can have a problem with having too high a cut in pressure setting, causing the compressor to stay off for ages after solenoid has been energized this can happen especially if there are two systems in one room and not much load. If it was a freezer i'd be setting the cut in at about 15 psi and an anti-cycle timer. Your setting is more for a chiller coldroom i'd say.

wilks
27-11-2007, 11:01 PM
sounds ok ,in fact on freezers you can have a problem with having too high a cut in pressure setting, causing the compressor to stay off for ages after solenoid has been energized this can happen especially if there are two systems in one room and not much load. If it was a freezer i'd be setting the cut in at about 15 psi and an anti-cycle timer. Your setting is more for a chiller coldroom i'd say.

yeah mate it is just 1 oC to 4 oC with 1 evap coil in it

stuartwking
29-11-2007, 12:10 AM
Hi Wilks,Your settings sound ok to me.Your diff will hold off your comp for longer,.I guess you could slightly change your diff but i would be happy with what you have.I think im right to say cut in + diff = running pressure.