Zone Control System Troubleshooting  

 Note: Take pictures of wiring before disconnecting from proper hook up. NEVER leave jumpers in place as the equipment will not turn off, leading to potentially dangerous temperatures.  Always disconnect 24vac power to zone board before applying jumpers, reconnect 24vac power when jumpers are in place.  

 

Jumper Test to verify the HVAC equipment

 Disconnect the low voltage wiring from the Zone control board equipment terminals. 

 1. Jumper R to W to verify furnace operation. 

2. Jumper R to G to verify fan operation.

3. Jumper R to G and Y to verify HVAC operation.

 If HVAC equipment proves to be fully operational, then test zone board. 

 

Jumper test to verify the Zone Board

 1.  Disconnect both thermostats at board, remove wires. 

You must disconnect wires from board.

2. Install jumpers from R to G on board terminals  and verify fan operation.  

3. While R to G jumper is installed, also jumper R to Y and see if compressor starts (avoid short cycling, and wait 5 minutes in case board time delays are delaying compressor start. 

3B. For Gas furnaces, jumper R to W or W1

3C. For heat pumps, consult factory.

4. Do above on zone 1, then zone 2.  DO NOT leave jumpers in place as HVAC  unit will never turn off. 

5. Damper check: Both Dampers should be open when no stat is calling. Opposite zone  damper should  close when jumpering zones. 

 Report back. YOU MUST remove thermostat wiring from board for this test. If zone board 

If HVAC unit performs as expected, the problem is likely in the thermostats or wiring. 

 

Jumper Test to Verify the thermostat wiring.  Kill power to zone board before attempting.  

 1. At thermostat location, remove thermostat from sub base.  With alligator clips, or with jumpers between thermostat terminals, jumper as follows:

2. Install jumpers from R to G on board terminals  and verify fan operation.  

3. While R to G jumper is installed, also jumper R to Y and see if compressor starts (avoid short cycling, and wait 5 minutes in case board time delays are delaying compressor start. 

3B. For Gas furnaces, jumper R to W or W1

3C. For heat pumps, consult factory.

4. Do above on zone 1, then zone 2.  DO NOT leave jumpers in place as unit will never turn off. 

 5. Damper Check: Both Dampers should be open when no thermostat is calling. Opposite zone  damper should  close when jumpering zones. 

 

Temporary HVAC equipment use, in the event of a bad zone control board,  by jumping a thermostat to equipment wires. disconnect all 24vac power first: 

1. Make sure all dampers are in the open position

2. Disconnect both thermostat wires (1 thermostat only) and equipment wires from panel

3. Connect thermostat to equipment wiring , NOTE: if thermostat is of the type to require a 24vac Common wire, this wire IS NOT used on zone control board, and will not be present. Use only a thermostat that requires no 24vac common wire (electro mechanical or battery powered)