Cause of error code Lockout 173

Pilot relay feedback incorrect.

1. External Electrical Noise
2. Failing Limit Switch in ILK circuit
3. Hardware failure of Sola controller

Solution for error code Lockout 173

1. Look for sources of electrical noise, i.e. a large motor or multiple pieces of equipment starting at the same time. 
2. Check operation of internal LWCO, and/or external limit (i.e. devise connected between “R” and “LIM”); replace as necessary. 
3. Reset power, If problem persists replace Sola controller.