airconlad
22-07-2015, 08:57 PM
Hi
I was called to service a car (Vauxhall Astra 2001 plate) and done the usual vacuum, pressure test oil / leak dye, vacuum and then re-gas and have come to a problem.
Standard R134a system
Currently suction side shows 40 - 43 PSIg and discharge shows 160 PSIg at around 21 Deg c / 74F.
When the Condenser cooling fan switches off the discharge rises to about 200 PSIg (as condenser temp rises)
Thing is the air con simply does not get cold but seems to be chucking more heat out on the evaporator side.
Checked the usual baffle plate stuck and hot / cold valve and all is correct so its not blowing heat from the heater matrix though the evaporator.
Compressor kicks in but runs constantly, if switch turned off clutch plate is released so it not stuck permanently on.
Prior to gassing I rotated it manually (as it had not been used / ran for some time) and comp turned as normal not rock solid or sticking.
System had lost most of its charge, still had about 8PSIg in it, vacuum pulled and held ok, nitro pressure test ok so no leaks.
When the system is on the condenser and receiver get red hot and I mean hot the condenser cooling fan kicks in and cools it down a bit, the discharge pipe up to the evaporator is quite warm and the suction from it is also stays warm.
I am not sure what is going on here, anyone have an idea.
Compressor seems ok to me as readings are for the ambient temp correct (give or take the couple of odd psi)
Could this be a blockage / faulty TEX valve on / in evap ?
Cheers
I was called to service a car (Vauxhall Astra 2001 plate) and done the usual vacuum, pressure test oil / leak dye, vacuum and then re-gas and have come to a problem.
Standard R134a system
Currently suction side shows 40 - 43 PSIg and discharge shows 160 PSIg at around 21 Deg c / 74F.
When the Condenser cooling fan switches off the discharge rises to about 200 PSIg (as condenser temp rises)
Thing is the air con simply does not get cold but seems to be chucking more heat out on the evaporator side.
Checked the usual baffle plate stuck and hot / cold valve and all is correct so its not blowing heat from the heater matrix though the evaporator.
Compressor kicks in but runs constantly, if switch turned off clutch plate is released so it not stuck permanently on.
Prior to gassing I rotated it manually (as it had not been used / ran for some time) and comp turned as normal not rock solid or sticking.
System had lost most of its charge, still had about 8PSIg in it, vacuum pulled and held ok, nitro pressure test ok so no leaks.
When the system is on the condenser and receiver get red hot and I mean hot the condenser cooling fan kicks in and cools it down a bit, the discharge pipe up to the evaporator is quite warm and the suction from it is also stays warm.
I am not sure what is going on here, anyone have an idea.
Compressor seems ok to me as readings are for the ambient temp correct (give or take the couple of odd psi)
Could this be a blockage / faulty TEX valve on / in evap ?
Cheers