LAARS NeoTherm NTV (Sizes 150–285 MBTU/h) - Service Manual - Manual (Page 28)

18
Service Manual NeoTherm 80 - NeoTherm 285
Checking the Low Water Cutoff Switch (option)
Control resets? Yes
No
Check for continuity from
base of switch to ground.
Has continuity? No
Isolate the boiler and drain it.
Remove the probe.
Do not use Teflon tape on the
threads. (This would interrupt the continuity).
Use “pipe dope” instead.
Check for water in boiler?
Yes
Water present? No
Yes
Check water supply, water pressure,
and auto makeup valve.
Reset low water cutoff control
Continued next page
Are you using ultra-pure water?
Ultra-pure water? Yes
No
Ultra-pure water will not conduct
electrical current = false low water reading
OK - temporary condition
B4