Tjernlund WHK-2 Millivolt Interlock Kit (Discontinued - Not Compatible with UC1) 8504026 Rev 8 09/98 - Manual (Page 10)

24 VAC CONNECTION TO WATER HEATER CONTROLS
Route the 25’ control cable to the water heater. Route control cable back to the heater controls along the ceiling or joists, taking care
not to come closer than 6” to the vent pipe or any other potentially hot surface.
In many cases, the gas supply piping can be used as a routing path from the ceiling down to the controls, using the supplied nylon
ties to secure the cable.
NOTE: If the distance between the WHK-2 Control Module and the heater controls is greater than the length of the cable, splice a
section of 3 conductor PVC sheathed, 105 degree C thermostat cable to the supplied cable. Make sure the colored leads remain consistent.
ACTUATING AND SAFETY CONTROL CIRCUIT CONNECTIONS
1. Push the BLACK piggy-back lead from the 6’ 18/2 Linear Limit sensing switch cable onto the common terminal of the Gas Pressure
Switch, (Diagram V).
2. Push the remaining BLACK lead from the 6’ 18/2 sensing switch cable onto one of the terminals on the Solenoid Valve, (Diagram W).
3. Push the YELLOW lead from the 25’ control cable onto the remaining terminal on the Solenoid Valve, (Diagram W).
4. Push the RED lead from the 25’ control cable onto the piggyback terminal joined with common on the Gas Pressure Switch, (Diagram V).
5. Push the BLUE lead from the 25’ control cable onto the normally open terminal on the Gas Pressure Switch, (Diagram V).
6. Plug the power cord from the WHK-2 into a grounded 115 VAC outlet. Verify that the outlet is powered through a 15 amp circuit breaker.
NOTE: The Power Venter may operate from 1 to 10 minutes when power is first established. This is due to any remaining time left on
the “post-purge” cycle of Relay/Timer after power has been interrupted. Wait until the Power Venter shuts off before continuing.
8
WHK-2 CONNECTED TO AN SS1
(FURNACE OR BOILER AND WATER HEATER COMMON VENTED)
DIAGRAM V DIAGRAM W