by Barry and Cindy 1997 U270 36′ 1/15/2007
The following notes should help you with this project.
We consider updating to the 5-button wall thermostat which required changing out the two roof air circuit boards, to be one of our most important motorhome upgrades.
Parts order:
(I would order double the amount of foam tape)
(did not need new standoffs as non broke in board change)
AC power module 310 9229.009 2
Comfort Control Center 310 9228.001 1
Standoff, PC board ( 4 req) 310 1624.017 8
Foam tape, 1-1/4″ x 1-1/4″ x 35″ 310 2669.029 4
Wall thermostat is replaced by unplugging the telephone type cable on the back.
Roof boards required removing big white plastic roof air conditioner covers and accessing the circuit boards behind a metal plate.
This work is done on the roof and we were able to do it ourselves.
About $100 for each board and wall thermostat, a total job of about $300.
Our roof air conditioners and furnace are much easier to manage.
Inside wires in the air intake area above the filter grill:
Zone 1 = FRONT AIR CONDITIONER
Zone 2 = REAR AIR CONDITIONER
| 110 Volt Power Wire Set | Purpose | Foretravel Wires | Foretravel wires |
| AC power | 110 v fan & compressor power | cable from street-side leg-1 | cable from curb-side leg-2 |
Air conditioner control wire set
Black RJ-11 Comfort Control Center
Gray RJ-11 into curb-side roof gray RJ-11 #38894 into the curb-side roof
Black RJ-11 Comfort Control Center
Gray RJ-11 #25023 into street-side roof n/c
White 2-wire plug remote temp sensor n/c white plug into the curb-side roof
Black wire 12 v – ground (to zone 1 only) to ground n/c
Red wire 12 v + power (to zone 1 only ?) white wire #10825023 into curb-side roof
White wire #10825023 into the curb-side roof
White wire #10825023 into the street-side roof
Blue wire, no polarity furnace thermostat white wire into street-side roof n/c
Blue wire, no polarity furnace thermostat green wire into street-side roof n/c
Yellow wire, no polarity load-shed / energy management n/c n/c
Comfort Control model # 3106463.007, 02-941101-E, 99023
n/c = no wires connected
System Reset instructions for later models
When dip switch is changed after initial configuration, reset required before Comfort Control will recognize the change
After setting the dip switches in the electronic control, do a system reset
Turn on/off switch to the off position
Simultaneously depress and hold the mode & zone buttons while turning on/off to on position
FF should appear in the display until the mode & zone buttons are released
Model 620×15 have heat strip and dip sw #1 is on
If the zone has a furnace, furnace dip sw #5 is on
When Load-Shed relay wants compressor off, the load-shed relay closes yellow wires to shut off the air conditioner compressor.
Not sure about 12 v + supply to both AC units as specs say 12 + only needed to zone 1
Rear board wiring:
Connector ID terminal color MH wire connection orig board MH this new board
RJ-11 P1 4 wires black comfort control y y
RJ-11 P2 4 wires black comfort control y y
2 wire P3 pair red n n
2 wire P4 pair white remote temp sensor y y
2 wire P5 pair blue freeze control y y
6 wire P6
1 yellow load shed y y
2 blue furnace
3 blue furnace
4 yellow load shed
5 black ground
6 red battery
Spade T1 black fan motor y y
T2 yellow fan motor y y
T3 red fan motor y y
T4 violet n/a n
Relay K1 spade T5 black wire to relay common (pre-wired onboard) n y
Spade NO black relay normal open y through the limit switch to heat element y
Relay K6 spade COM black common y 110v hot y
Spade NO black normal open y compressor y
Dip switch
1 heat strip y y
2 zone 2 y y
3 zone 3
4 zone 4
5 furnace
6 differential
7 stage
8 gen start
Fuse spade F1 3 amp purple fuse
Round run capacitor red through PTCR to run cap, compressor white heating element
Oval run capacitor brown fan motor
White motor, neutral 110v, heating element
Red compressor
Front board wiring:
Connector ID terminal color MH wire connection original board MH this new board
RJ-11 P1 4 wires black comfort control y y
RJ-11 P2 4 wires black comfort control y y
2 wire P3 pair red n n
2 wire P4 pair white remote temp sensor y y
2 wire P5 pair blue freeze control y y
6 wire P6
1 yellow load shed y y
2 blue furnace
3 blue furnace
4 yellow load shed
5 black ground
6 red battery
Spade T1 black fan motor y y
T2 yellow fan motor y y
T3 red fan motor y y
T4 violet n/a n
Relay K1 spade T5 black wire to relay common (pre-wired onboard) n y
Spade NO black relay normal open y through the limit switch to heat element y
Relay K6 spade COM black common y 110v hot y
Spade NO black normal open y compressor y
Dip switches
1 heat strip y y
2 zone 2
3 zone 3
4 zone 4
5 furnace y y
6 differential
7 stage
8 gen start
Fuse spade F1 3 amp purple fuse
Round run capacitor red through PTCR to run cap,
Compressor white heating element
Oval run capacitor brown fan motor
White motor, neutral 110v, heating element
Red compressor