tracker economizer issues
Hey guys, went out to a call with another tech tonight, not an emergency but something changed they said. So we have a trane rtu 10 ton ( i think) with 4 electric vav boxs and a bypass and controlled with Tranes tracker and CCP panel
The problem is that the space has been over heating the past few days but yet the system has been in for over 7 months and nothing but perfect. So the outdoor temp has been upper 40s and 50s. So we went there tonight since we have some extra time and found the economizer not opening. When you go the control panel it shows the MIN OA damper is set at 20% and when you increase the MIN OA damper setting it opens with no problems and evetually the power exhaust kicks in.
So we have 3-4 strong cooling votes and the economizer will not open and the mechanical cooling does not kick in. The control panel says "OK to economize Yes" and yet it does not go into cooling. Discharge air temp is around 70
I need more info like model and serial numbers but we will be back.
just some things off the top of my head..... i may not even be close.
has the enthalpy control been set? usually i would set it at "d" or "E"
did the mix air temp sensor maybe not get wired? or maybe the wires came loose?
when you go back check to make sure that the ccp is setup for two stage operation. if the econo cannot keep up, the unit should enable mechanical cooling. also check to make sure their is not a problem with the mechanical cooling.
it sounds like you may have 2 problems. econo and mechanical cool.
hope this helps