Hatco Imperial Series Installation And Operating Manual page 30

TROUBLESHOOTING GUIDE
WARNING
This unit must be serviced by qualified personnel only.
Service by unqualified personnel may lead to electric
shock or burn.
Symptom
Water at dishmachine is not at
the proper temperature.
Heating elements burn out.
Relief valve dribbles.
Relief valve opens.
High temperature limit trips.
Chattering contactor or low
water cutoff circuit board
Probable Cause
Gauge(s) not working properly.
Thermostat set too low.
Booster heater has more than 1524 linear
millimeters (5') of water pipe to the
dishwasher, causing the water to cool off
inside the pipe.
Tank inadvertently drained
elements in a dry condition.
Lime buildup in tank causing elements to
split and burn out.
No pressure reducing valve installed or
incorrect valve installed causing pressure
build-up inside booster tank.
Bypass in pressure reducing valve may be
blocked.
Check valve or anti-siphon valve installed in
the feed line.
Unit is overheating.
Contactor may be sticking in closed
position not allowing unit to cycle off.
Temperature limit set too low.
Thermostat set too high.
Incoming water temperature too high
causing nuisance tripping
temperature limit switch.
Loose connections or wire connection has
insulation under crimp.
Low voltage.
Probe may be fouled.
Contactor(s) may be bad.
ELECTRIC SHOCK HAzARD: Turn power OFF at
disconnect switch/circuit breaker and allow unit to cool
before performing any maintenance or cleaning.
Check
thermometer to be certain gauges are working
correctly. If not, replace gauge(s).
adjust or recalibrate. If thermostat will not
recalibrate properly, replace it.
If located farther than 1524 linear millimeters
(5'), pipes should be wrapped in insulation,
and/or a recirculating system installed.
leaving make sure tank is full of water at all times.
Check low water cut-off system for proper
operation.
Clean or delime tanks periodically. a water
softener or blended phosphate treatment
system may be required.
a pressure reducing valve with high pressure
bypass must be installed in the incoming water
line to allow water to expand back into the
feed line.
Clean bypass or replace with new valve with
built in bypass.
Remove check valve or anti-siphon valve to
allow for water expansion or install a back
pressure relief valve on the incoming water
line, Hatco P/N 03.02.039.00.
Thermostat may be set too high or is sticking.
Recalibrate or replace the thermostat.
Replace contactor(s).
If booster heater is not overheating, replace
High Limit Safety Switch.
adjust or recalibrate to proper temperature.
Incoming water temperature should not be
of high higher than 71°C (160°F).
Tighten all connections and check crimps
Check control circuit voltage or secondary
voltage with transformer.
Bypass probe by removing wire from low
water cutoff probe and grounding to tank.
Clean or replace probe if chattering stops.
Test contactor coils and replace if needed.
30
English
WARNING
Corrective Action
temperature of water
Form No. EBOOSTERm_CN-0911
with a