trane ewkh400ddw package system help

[stevo4546]

Hi guys,

Been called to a trane package system today model ewkh400ddw type 376367-1.

switched system back on and called for both circuits in heating mode via test push button. both circuits start and heat coming onto evap coil but after short period system trips on high pressure. I have checked evap fan going correct way & reversing valve and all correct, switched over to cooling mode and found pressures very low 3 bar and 18 bar for r410a. - system running on r410a which should be higher.

System has a pre heat coil and a lphw coil and they are fine but only when refrigeration side called for it trips on hp in heating mode and low pressures in cooling as stated previously.

Heat and cool coming onto evap when both modes called for.

There are 2 x exhaust fans at inlet to package unit which i cant seem to get running in any mode.

[install monkey]

exhaust fans for when its running in free cooling- full fresh air- 2 exhaust fans kick in to dump the return air.
as for ur hp issue- 3 bar suction- check for choked driers, check valves operational and degass it to comfirm charge

[stevo4546]

Hi install monkey

Heading back tomorrow to check system,

Driers seemed to be OK as there is 2 x per circuit and temperature either side was the same, can t remember seeing any check valves though on circuits but will check again.

thanks for help

[install monkey]

http://www.trane.com/WEBCACHE/UN/ROO...4_08012014.PDF
hope this is useful