Lennox Error Code 370

Priority condition: Service Urgent Communicating Mode: Priority condition: Service Urgent NOTE: The on-board jumper DS-R (W914) will be cut. In communicating mode, the DS-R terminal is used with the EL296 and SL280 furnaces and will be used to monitor a field-installed interlock switch such as for example a float switch. When operating in this capacity, the DS jumper will be monitored as follows: • When no alert codes are present there will be 24VAC present at this terminal. • When control see the loss of 24VAC for two minutes it will send an alert code 370 and disable heating function. • If currently running a demand it will de-energize all outputs (including the blower). • In case of an existing interlock switch alert code, upon power reset, an alert code message will be sent if voltage is not sensed on the DS terminal. • An alert code clearing message will be sent if 24VAC is sensed on DS terminal for the minimum of 10 seconds. • The monitoring of DS terminal will apply to both variable speed and constant torque controls. Priority condition: Service Urgent Non-Communicating Mode: Priority condition: Service Urgent NOTE: The on-board jumper DS-R (W914) will NOT be cut. The furnace control has not received 24VAC power for two minutes or more on the DS terminal • The system will not operate. • Dealer has cut the W914 jumper (Dehum, Harmony III) on the Lennox furnace control. • The thermostat monitors the DS terminal in the furnace for power and if the link has been cut then power will be lost to DS. • If DS to R terminal is accidentally cut you must reconnect a jumper from the DS to R on the terminals strip.