Need Help - TRANE Office A/C

[Shack]

Hi All,

We have just installed a new TRANE system. It is a 10ton unit. The outside unit is a Model TTA120B300EA and the inside air handler is a TWE120A300EL. The outside unit appears to be a dual circuit unit and the inside is only a single. We piped both outlets from the outside unit together so that only one pipe is going to the inside unit. The compressors are tripping on high pressure. We want to know if you can use a dual circuit outside unit with a single circuit air handler.

Thanks!

[Brian_UK]

Firstly, what does the instruction manual say about the installation requirements?

I would suggest that only one circuit should be connected to the indoor unit and the unused compressor disabled electrically.

The high pressure fault could be because you now have two pumps pumping into one unit.

[Don Davis]

For what it's worth, my experience is with much larger evaporative condensers but it's very common to connect numerous condenser coils in parallel- even multiple evaporative condensers. When I think about it, it's just an extension of the parallel circuits found inside a single coil, right?

[The Viking]

Right, but maybe not right?

It will all depend on how the individual outdoor circuits are designed...

How are they controlled?
Are there solenoid valves and if so where?
What has been done about oil balancing?
Will a running compressor be able to suck all the gas in to it's condensor, effectively draining the the other condensor?
Is there receivers/accumulators to cope with the various running conditions?

The list goes on...

[wambat]

Hi All,

We have just installed a new TRANE system. It is a 10ton unit. The outside unit is a Model TTA120B300EA and the inside air handler is a TWE120A300EL. The outside unit appears to be a dual circuit unit and the inside is only a single. We piped both outlets from the outside unit together so that only one pipe is going to the inside unit. The compressors are tripping on high pressure. We want to know if you can use a dual circuit outside unit with a single circuit air handler.

Thanks!

I would say yes if you don't want to use 1 circit you seem to have the single circuit indoor supply fan you need the "B" model and you certainly don't want to hook up both compressors to 1 circuit

[bruceboldy]

I will look into the dual manifold set up It should be fine with the TWE unit .
a tta 120 matches with the TWE 120 .
The TWE also is belt drive. You may need to up the fan speed . If you only use one compressor you get 50 percent capacity. It is common to have the two manifolded together.

bruceboldy