Thermo King on truck box

[metricwrench]

I got this unit model # STB11E, B/M 711552, series 0863573767
The compressor is mounted on the engine(Sanden)
The condenser above the cab. When the system is activated by the switch in the cab, the clutch cycle on & off like if there was a short. I disconnected the the wire for the clutch & hot wired(monitoring with the gauges) While the ambient temp was 80F, the high side when to 350(I release the power to the clutch) & the low side came down to 30, & it took a long time to equalize(5 minutes +). I think there may be some blockage.
Any Manual or input to repair this unit. I got gauges , vacuum pump, just not that familiar with TK ref unit.
manual would be nice? shadow@harleydeals.net
wrench

[abbsnowman]

Sounds like non condensables to me. Pull the charge and weigh it. Pressure test, (posative and with vac. pump), then if she passes, change drier and put a fresh charge in.
Oh, by the way, is condenser fan coming on? It should come on and then go off when pressure drops to acceptable amount.

[climas]

Five minutes is not long time to equalize pressure.Check pressure switch, I have same problem,and do what abbsnowman say

[DTKServices]

I agree with you I had several STB's I had to maintain and 5 Min's does sound like a while for pressures to EQ. I'm not saying you can't have none condensible in your system, but even if you did they would EQ at a fairly normal rate. A Blockage in the High side would better explain a slow EQ time.

On this unit they some times have a oil separator mounted somewhere in the high side line. I would pray and look the oil separator first, other wise you'll be looking to disassemble a 3 way valve to clean a screen..

As you'll have to pull the charge anyway I'd check for non condensible like the others mentioned before anything else. (By weighing out what you recovered) and then look for a blockage...

[cadwaladr]

what refrigerant is it on the condensor fan is brought in by a pressure switch on the high side put a hot feed direct to the motor to test the item

[metricwrench]

Thanks everyone,
The system is loaded with 134A, I found an installation manual for the V-500, Is this close to the STBII?
I don't have a recovering station. The unit is in bad shape( no cover, rusty comportment, condenser fan missing). Will check for the oil separator. There is a magnetic valve, I think it may be the defrost valve? There should be some where to get a manual for that model?
thanks again

[DTKServices]

A CB or CBci would be the next closest model..

You NEED a condenser fan! Fix this before you go any further.

You can check eBay for a manual.