piping question

[reggio]

help, I have a trane 50 ton condencer (rauc-c50) with a 1 evaporator and 1 txv, the condencer came out with 2 circuits a first and second stage. my ? is can i pipe the second stage into the first stage piping and ru one circuit to the evap.

[traneman1]

What type of air handler do you have? What is the model? Is it a 2 circuit type? I will need more info to help you out. Is your TXV rated for 50 tons?

[reggio]

thx for the reply, im not sure the m# my clipboard is on the job, but is a trane climatemaster hot and cold deck. the ahu has a 100 ton evap that is split up with 2circuits at 50 tons. iam relacing the txv and yes it is a 50ton txv. iam replacing one of the 50 ton condecers.

[reggio]

not paying attention to my spelling ,kids wont leave me alone

[bobby m]

sounds like someone ordered a condensor that isnt suitable for application,if it has two compressors and common piping it should be ok to use,but if there are two independant refr. circuits it may be risky and tricky on control end .if thats the case dont forget about oil equalizer between compressors,i would consult trane sales engineer(ha ha) if possible. get second opinion before piping this or you will live a nightmare

[fatboy]

I agree with BobbyM

cond was misordered.

most OEM's don't offer a 40+tonnage unit in a single circuit anymore, I believe Mcq and AAON do, all others are custom made

You may have to remove the 50t evap coil and have 2 25t custom coils made

fatboy

[tonymjr]

50 tons is 50 tons. If the condenser has 2 discharge and 2 liquid connections they can be tied together with a piping kit from the manufacturer to allow for correct psi drop thru the coil.

[trimble]

You CANNOT use a dual circuit 50 ton condenser with a single circuit evaporator. Simply tying the suction and liquid lines together won't work. You need to have an oil equalizer line between the compressors or eventually one compressor will run dry. Even if you installed an oil equalizer line, the hot gas lines must also be tied together or refrigerant will back feed through the liquid line into the condenser of the circuit that isn’t running and stack in that condenser. The circuit that is running will act like it is low on refrigerant. Then you will also have to modify the controls. If you do make all these changes, you are significantly changing the units design.

I’ve been down this road before straitening out another contractors mess.

[islandcool]

Originally posted by tonymjr
50 tons is 50 tons. If the condenser has 2 discharge and 2 liquid connections they can be tied together with a piping kit from the manufacturer to allow for correct psi drop thru the coil.

NOT!!!!! Let Tony try it!!!!!!!!!!!!

[islandcool]

Originally posted by txtraneman
You CANNOT use a dual circuit 50 ton condenser with a single circuit evaporator. Simply tying the suction and liquid lines together won't work. You need to have an oil equalizer line between the compressors or eventually one compressor will run dry. Even if you installed an oil equalizer line, the hot gas lines must also be tied together or refrigerant will back feed through the liquid line into the condenser of the circuit that isn’t running and stack in that condenser. The circuit that is running will act like it is low on refrigerant. Then you will also have to modify the controls. If you do make all these changes, you are significantly changing the units design.

I’ve been down this road before straitening out another contractors mess.

Exactly!!! This is the way to go!!!

[bruiseandy]

worked on a lot of the RAUC systems in the air force. The 50 cannot be tied together for a couple reasons. First of all like they said oil equalizer lines, second is controls. You'll burn up components like mad , lot of solid state stuff in that control panel, time delay relay on that guy is $183 if I remember right and that was 2 years ago`

[tonymjr]

Sorry, nobody said the compressors were in the condensers or that there were two. I thought it was a built up system with the compressor (1) stacked atop the evap.