Boiler Safety Limit Open
Boiler Safety Limit, or External Limit wired to terminals J5-1 OPEN:
• Jumper for External Limit wired to terminals 11 and 12 or device connected to it open.
• See possible causes for “Hard Lockout 4”.
• Loose wiring to limit device.
• External Limit defective or jumper not installed.
• If yellow light on LWCO is on, system is low on water.
• If neither yellow or green light is on, check LWCO harness.
