Super Hot EPJ-119-SC, Installation And Service Manual

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EPJ SERIES INDIRECT WATER HEATERS – Installation and Service Manual
24
Troubleshooting Guide Section 8
Problem Possible Cause Solution
No Hot Water
Tank control failure

Check wiring and power supply

Replace control
Aquastat not calling for heat
 Check wiring
 Replace aquastat
Air lock in domestic water loop

Purge and bleed piping
Circulator not operating

Repair or replace circulator
Zone valve not operating
 Check wiring and power supply /
open manually to check
 Replace zone valve
Boiler not operating

Boiler control too low
 Check wiring

Check disconnect switch
 Check fuse or circuit breaker
 Check wiring and power supply
Insufficient Hot Water
Temperature setting too low
 Adjust aquastat or tempering valve
to higher setting
Defective aquastat or improper
calibration
 Replace aquastat
Undersized water heater

Install adequate water heater
Undersized boiler with no priority to
domestic hot water
 Rewire for priority / check sizing
Slow Hot Water
Recovery
Undersized boiler with no priority to
domestic hot water
 Rewire for priority / check sizing
Inadequate boiler water flow

Check circulator sizing

Ensure valve is open
 Purge and bleed piping
Circulator capacity too low

Replace circulator with correct one
Scale build-up in tank
 Chemical cleaning or repeated
flushing
Water Too Hot
Aquastat setting too high

Adjust aquastat to lower setting
Aquastat continuously runs

Check wiring

Replace aquastat
Improper system piping and/or control

Check piping and flow control
valve
Improper system wiring
 Check wiring
Tempering (mixing) valve
 Read valve instructions or consult
with manufacturer
Discharge From T&P
Relief Valve Inlet cold water pressure too high

Install pressure reducing valve
Excessive water pressure when
heating

Install properly sized potable
thermal expansion tank on cold
water inlet
T&P Relief valve leaking
 Replace T&P relief valve