Lochinvar NSF SSB-i & s--01 - Manual (Page 5)

CAUSE B
Control thermostat may be set too high or be defective.
SOLUTION - Reset thermostat(s). If condition is not
corrected, replace thermostat(s).
CHATTERING CONTACTOR(S) OR NOISY RELAY.
CAUSE A
Contactors chatter or hum excessively when pulled in.
SOLUTION - Accumulation of dirt will prevent proper
seating of armature. Remove contactor and clean. If proper
seating is prevented by warpage of the frame or distorted
coil, contactor should be replaced. Check for loose
connections or wire connections with insulation under crimp.
CAUSE B
Contactors chatter only at pull-in or drop-out, or low water cutoff relay
is noisy.
SOLUTION - Check for low voltage at control circuit and
at secondary side of transformer. If voltage is below 120
volts, replace transformer. Low water cutoff probe may be
fouled. To check, remove wire from LWCO probe and
ground to tank. If LWCO board relay pulls in and stops
chattering, the probe is fouled. To clean, drain water from
tank, remove probe and clean probe tip.
THERMOSTAT
ADJUSTMENT AND RECALIBRATION
The thermostats are factory calibrated to produce 185-190ºF
(85-88ºC) temperatures. If recalibration is necessary, turn screw (G)
counterclockwise to lower the set point or turn the adjustment nut (F)
counterclockwise to raise the set point (must hold screw (G) at high
stop). NOTE: one-sixth of a turn equals 12ºF (6.7ºC).
These thermostats are checked and accurately set at out factory. If
recalibration is necessary, a 1/4 turn clockwise to screw (F) will
decrease the temperature 12ºF (6.7ºC).
REMOVAL
1. Shut off power and drain tank; remove leads from
terminals (E).
2. Loosen nut (A), then remove bushing (B) from tank.
Thermostat with bracket and sensor bulb (C) can now
be removed from tank.
INSTALLATION
1. Pull end of sensor bulb (C) into recess in bushing (B).
2. Insert bushing (B) and sensor bulb into tank;
holding sensor bulb in place with capillary tube,
tighten bushing (B).
3. Lock sensor bulb and capillary tube in place by
tightening nut (A).
4. Replace thermostat on bracket. Replace leads
on thermostat terminals.
Be sure tank is filled with water before turning on power.
CAUTION !!
Do not overtighten nut, or sleeve inside of bushing
will cut through tubing.
CAUTION !!
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