[Chester Stone]

After getting #1 rear compressor running as posted on a different thread, I set about to install the heavy duty relays and am posting photos of my work.  But first, when I started disconnecting all of the wiring going to the front A/C unit, the connector going from the board to the #1 compressor was burnt and pulled out of the control board.  I soldered in a new, but different, connector and here is a photo of the burnt connector.  The compressor was running correctly before I started so I guess I should have installed the relays much sooner.
   

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Attached is a schematic drawing that shows how the relays were to be connected, and with the help and confirmation by Richard.
   

[Chester Stone]

Attached are photos of the relay box as wired, and the top and bottom sections of the control board.  Hope this helps. 
           

[Chester Stone]

I made a color error on the schematic.  New one attached.
   

[MrE]

Most excellent post Chester, thank you!

[Richard]

Very Nice !

Neat installation, nice touch to put shrink tubing on the connectors.

I am not glad you found the burned connector, but it illustrates one of the weaknesses of the board that the relays circumvent. Finding stuff like that makes the time and expense to install the relays worthwhile, cause you know it was a matter of time before that circuit failed.

I truly am impressed that you condensed the essence of the wiring change into one crystal clear diagram. I could never explain it that well. Thank you, and thank you for all the gurus in the future who make this improvement.

[folivier]

And thank you Chester, Richard, Russ, and others who found out the problem and came up with the relay fix. I really liked the SCS a/cs in my '98 and this fix should make them pretty bulletproof.
Now if only Newell would have made more coaches less than 40' I'd be looking for my next coach.

[Fasteddie]

Chester is there a chance you rember the part numbers of the relays you used in your post? Looks like Eaton is the mfg, but can not read anything else. If not what is the electrical specifactons needed for the conversion? Great post and need to do the same on my 98. 

Ed Thomas
[email protected]

[Chester Stone]

Ed, using Photoshop I enlarged a photo of one of the relays. They are EATON Cat. No. C25ANB125A. Not sure if the N is not a M. If this does not help you, let me know and I will do more research. There is a posting on this forum which shows a different source and I have copied it here: I used these relays. https://www.mcmaster.com/#definite-purpo...s/=14w52m6 25 amp contacts, and make sure you get 120V control voltage. You can probably find them cheaper.

[Fasteddie]

Ed, using Photoshop I enlarged a photo of one of the relays.  They are EATON Cat. No. C25ANB125A.  Not sure if the N is not a M.  If this does not help you, let me know and I will do more research.  There is a posting on this forum which shows a different source and I have copied it here:  I used these relays.  https://www.mcmaster.com/#definite-purpo...s/=14w52m6  25 amp contacts, and make sure you get 120V control voltage. You can probably find them cheaper.

Thanks I went back to the photo you had of the relays and enlarged them and saw the part number. I all ready ordered them 4 pcs. I guess you only need two for both front and rear a/c s, but have spares if needed. Only $14 ea. Y
Thanks for you quick response.

[Richard]

You will use all four. You have four compressors.