1801 Commercial Electric Water Heater Troubleshoot

User Manual: Commercial-electric-water-heater-troubleshoot

Open the PDF directly: View PDF PDF.
Page Count: 3

TECHNICAL SERVICE DEPARTMENT
Technical Service Bulletin
1-800-432-8373
Commercial Electric Troubleshooting Tables
Technical Competence, Product Confidence
Page 1 of 3
1801.doc
NATURE OF
TROUBLE POSSIBLE CAUSES SERVICE
No Hot Water Manual switch turned off
Blown service panel fuse or breaker
High limit switch tripped
Thermostat faulty
Faulty contactors (open)
One or both transformer fuses are blown
Thermostat out of calibration
Improper wiring
a. Shorted or loose wiring
b. Undersized service wire
Turn to ON
Replace or reset
Manually reset ECO button
Check and replace
Check and replace
Check and replace
Check and replace
Check and rewire
Rewire per wiring diagram
Not Enough Hot Water Thermostat set too low
Faulty element(s)
Faulty Contactors (open)
Faulty fuse on fuse block
Improper or loose wiring
Improper heating elements
Scale formation on heating elements
Thermostat not flush with tank
Poor grounding of tank
Heater is undersized
Damaged dip tube (ELDs only)
Increase thermostat
Check for open or grounded elements and
replace
Check and replace
Check and replace
Rewire per wiring diagram
Check and tighten
Check wattage/voltage to rating plate and
replace
Check elements; clean or replace
Position thermostat so back touches the
tank. Make sure cavity insulation covers
thermostat
Check grounding and tighten
Resize and compare
Check and replace
Water too hot Thermostat setting too high
Thermostat out of calibration
Thermostat not flush with tank
Faulty contactors (closed)
Lower thermostat setting
Check and replace
Position thermostat so back touches the
tank
Check contactors and replace
Blows fuses and / or trips
breaker
One or more elements are grounded
Loose terminal screws on heating
element(s)
Faulty contactors
Undersized heater
Check and replace
Check and tighten
Check contactors and replace
Resize and compare
Slow hot water recovery Heating elements too small
Faulty contactors
Fuses on fuse block are blown
Check wattage and replace
Check contactors and replace
Check fuses and replace
http://waterheatertimer.org/How-to-wire-water-heater-thermostats.html
http://waterheatertimer.org/3-phase-water-heater.html
TECHNICAL SERVICE DEPARTMENT
Technical Service Bulletin
1-800-432-8373
Commercial Electric Troubleshooting Tables
Technical Competence, Product Confidence
Page 2 of 3
1801.doc
NATURE OF
TROUBLE POSSIBLE CAUSES SERVICE
Noisy water heater Scale build-up on elements
High watt density elements in the heater
Contactors are ‘chattering’
Remove, clean or replace
Install low watt density elements
Check for foreign material in the
contactors. Check for broken or weak
spring
Excessive relief valve
operation
Excessive water pressure
(just a little water from the T&P)
Excessive temperature
( a whole bunch of water from the T&P)
Install proper expansion tank on cold side
Check for open or closed system. Install
thermal expansion tank
Check thermostat; lower setting or
replace.
Thermostat not flush with tank
Check contactors to see if two or more
are closed.
Rusty or black water Scale formation on elements
Anode rod dissolved
Excessive sediment build-up
Clean or replace elements
Check anode rod and replace
Try to drain tank; replace tank if sediment
build up is excessive
Water heater is leaking
(Caution: Do not confuse
normal T&P operation as
a leaking tank. If the
puddle dries up, then look
for a T&P problem.)
Cold in or hot out joints
T&P valve
Heating elements, anode rod and gaskets
Inner tank has a pin hole
Check joint and repair
Check valve and replace
Check, tighten and replace
Replace water heater
(When diagnosing a leaker - you will
notice a puddle of water on the floor, next
to the heater, that will not go away.)
TECHNICAL SERVICE DEPARTMENT
Technical Service Bulletin
1-800-432-8373
Commercial Electric Troubleshooting Tables
Technical Competence, Product Confidence
Page 3 of 3
1801.doc
Multi-Stages, Series and Parallel Installation
NATURE OF
TROUBLE POSSIBLE CAUSES SERVICE
No Hot Water Manual switch turned off
Blown service panel fuse or breaker
tripped
High limit switch tripped
Thermostats faulty
Faulty contactors (open)
One or both transformer fuses are blown
Thermostat out of calibration
Improper wiring
a. Shorted or loose wiring
b. Undersized service wire
Turn to ON
Replace or reset
Manually reset ECO button
Check and replace
Check and replace
Check and replace
Check and replace
Check and rewire
Rewire per wiring diagram
Not Enough Hot Water Thermostats set too low
Faulty element(s)
Faulty Contactors (open)
Faulty fuse on fuse block
Improper or loose wiring
Improper heating elements
Poor grounding of tank
Heater is undersized
Increase thermostat setting
Check for open or grounded elements and
replace
Check and replace
Check and replace
Rewire per wiring diagram
Check and tighten
Check wattage/voltage to rating plate and
replace
Check grounding and tighten
Resize and compare
Water too hot Thermostat setting too high
Thermostat out of calibration
Faulty contactors (closed)
Lower thermostat setting
Check and replace
Check contactors and replace
Blows fuses and / or trips
breaker
One or more elements are grounded
Loose terminal screws on heating
element(s)
Faulty contactors
Undersized heater
Check and replace
Check and tighten
Check contactors and replace
Resize and compare

Navigation menu