© 2022 Staheli West
148
Faults
Fault 209: Feed Water and Boiler Water Temp. Differential Limit Has Exceeded
Indicates that the difference in temperature between the feed water temperature sensor and the boiler
water temperature sensor is more than 150° F.
Causes
Troubleshooting
Fixes
• Clogged/Dirty Y-Strainer.
• Flush Y-Strainer by opening for 3 seconds
under steam pressure.
• Clean/replace
Y-Strainer filter. (See 250 hr
maintenance for filter removal)
• Circulation pump isolation
valves are closed.
• Check valve positions (both
circulation pump inlet and outlet
valves).
• Open valves (both circulation
pump inlet and outlet valves).
• Faulty temperature sensor.
• Compare reading with actual
temperature (Faulty sensors
normally read very high or very
low).
• Replace sensor.
Cir
cula
tion Pump not running
• Pump contactor overload is
tripped.
• Inspect circulation pump
contactor; if yellow stripe is
present in test window, reset is
required.
• Reset pump contactor overload
(Panel 2).
• Circuit breaker is tripped.
• Check circuit breaker (Panel 1).
• Reset circulation pump
circuit
breaker (Panel 1).
• Yellow weatherproof 240 V
plug loose/disconnected.
• Inspect yellow weatherproof
plug to see if it is loose or has a
bad connection.
• Reconnect yellow weatherproof
plug behind the burner that gives
240 V to the pump.
• Loose wires inside pump
motor housing.
• Inspect wire nuts and ensure
that 240 V is reaching the pump.
• Secure wire nuts inside pump
motor housing.
• Faulty/Seized pump.
• Manually attempt to spin motor
(motor should spin freely).
• Replace pump.
• Water system not enabled
on touch screen.
• Circulation pump should be
running anytime water system is
enabled and low water 1 & 2 are
satisfied.
• Enable water system (Menu >
Operations > System Start).
• Faulty relay between PLC
and motor contactor.
• Check relay to see if light is on
(Panel 2 relay block 2nd relay).
• Replace relay.
• PLC output not sending
signal.
• Check for 24 V on PLC output
“Y5” (Menu > Diagnostics >
Inputs/Outputs > Discrete
Outputs > Y5).
• Replace PLC.