Trane RAUJ 40 ton - wiring and sequence questions

[Ancoma Tom]

Could someone tell me the function and time delay settings of time delay relays 1DL8 and 1DL9?

Also reset relays 1K11 and 1K12 appear that the coils would be deenergized anytime there is not an open safety control and would energize and lockout their circuit if a safety opens, is that correct? I assume power has to be dropped from the control circuit for them to reset?

Last question is related to compressor sequencing. The manual shows that step 3 (75% capacity) would be Circuit 1 - both compressors 1A and 1B as well as Circuit 2 - compressor 2A. However, after tracing out the wiring it appears that Step 3 is actually Circuit 1 - compressor 1A and Circuit 2 - compressors 2A and 2B, is the manual wrong? Wiring diagram is 2307-9208.

Thanks for any input.

[jayguy]

i don't have an RAUJ wiring diagram, but it is probably similar to the RAUC.

the 1DL8 and 9 relays are time delays that will force the refrigerant circuit to stay energized for a minimum of 3 minutes once it has started.

you are correct on the 1K11 and 12 lockout relays.

step 3 (without any safeties tripped out) would be both compressors on Circuit #2 ON and Compressor 1A on Circuit #1 ON. Compressor 1B would not be running.

in SS-SVX11G-EN 01232012, page 113, it does say that Circuit #1 would be fully loaded and Compressor 2A would be ON. again, I don't have the wiring diagram to know if they have changed things since the RAUC manual. it could be a 'cut-n-paste' error...i would trust the wiring diagram more than the manual.

[Ancoma Tom]

Jayguy,
Thanks for the reply. I was able to go through my local Trane salesman yesterday to conference in with a factory technical service rep and did get some answers. I'm not sure why they are so protective of not allowing us to call technical service direct...but I digress.

Actually the 1DL8 and 1DL9 time delay relays are 3/10 second delay on make relays. He explained that they are there to prevent any chatter on the 1K15 or 1K16 contacts from causing nuisance trips.

The table in the manual is incorrect as far as the sequencing goes. Step three is actually Circuit 1 compressor 1A and both compressors on Circuit 2.

Thanks again.