Hubbell Electric Heater Company EMV User Manual
12
SECTION IV –
TROUBLESHOOTING
Symptom
Probable Cause
Corrective Action / Remedy
Circuit breaker tripped at source.
Reset circuit breaker.
High limit switch tripped.
Reset high limit switch.
Loose wires.
Torque screws holding wires.
Heating element inoperable.
Check heating element operation by clamping
an Amprobe around each wire to the element.
The ampere reading should agree with the
nameplate ‘AMP’ figure.
an Amprobe around each wire to the element.
The ampere reading should agree with the
nameplate ‘AMP’ figure.
Low line voltage.
Have source electrical system checked by an
electrician.
electrician.
No hot water in tank
Faulty thermostat.
Move thermostat dial through full range. A
definite ‘click’ should be heard. If not, replace
thermostat.
definite ‘click’ should be heard. If not, replace
thermostat.
Faulty thermostat.
Check thermostat adjustment. Monitor
thermostat as described in Section III,
Quarterly Inspection. Replace if necessary.
thermostat as described in Section III,
Quarterly Inspection. Replace if necessary.
Heating element not working on all
phases
phases
Check to see that heating element is working
on all phases, by checking the resistance
(ohms) value for each element and comparing
with the chart included in Section VI.
on all phases, by checking the resistance
(ohms) value for each element and comparing
with the chart included in Section VI.
Water temperature in
tank below settings at
all times
tank below settings at
all times
Heater improperly sized
Verify heater is properly sized for the flow rate
and temperature rise of your system. Replace
elements with proper size as necessary.
and temperature rise of your system. Replace
elements with proper size as necessary.
Relief valve discharges
continuously
continuously
Excessive temperature or pressure
in tank
in tank
Temperature and pressure relief valves are
made to operate if the water temperature
exceeds 210
made to operate if the water temperature
exceeds 210
°F or water pressure exceeds the
pressure rating of the safety relief valve. If
trouble is excessive temperature, then
thermostat is not shutting off at the right setting
and thermostat must be replaced.
trouble is excessive temperature, then
thermostat is not shutting off at the right setting
and thermostat must be replaced.
Blockage in cold water inlet to
mixing valve
mixing valve
Disconnect mixing valve and clean out cold
water inlet pipe.
water inlet pipe.
Tepid water
temperature too hot
temperature too hot
Mixing valve out of calibration
Re-calibrate mixing valve as described in
Section V, Service and Replacement of Parts,
Re-Calibrate Mixing Valve.
Section V, Service and Replacement of Parts,
Re-Calibrate Mixing Valve.
Blockage in hot water inlet to
mixing valve
mixing valve
Disconnect mixing valve and clean out hot
water inlet pipe.
water inlet pipe.
Tepid water
temperature too cold
temperature too cold
Mixing valve out of calibration
Re-calibrate mixing valve as described in
Section V, Service and Replacement of Parts,
Re-Calibrate Mixing Valve.
Section V, Service and Replacement of Parts,
Re-Calibrate Mixing Valve.