American Water Heater ADCG Check continuity, Across ECO, Is ECO light on?, Power, Is turned up

Index

DCG3 SERIES

COMMERCIAL GAS DAMPERED WATER HEATERS

High water temp.

YES

Will ECO light

Check continuity

Replace

No Hot Water

reset once temp.

NO

across ECO

OPEN

ECO

in tank cools?

Go to

Power to

CLOSED

thermostat

NO

Is ECO light on?

troubleshooting

heater?

YES

NO

flow chart

Repair

YES

Check for 24V

Is ground good

power

When thermostat

NO

between purple

NO

NO

problem

from control

is turned up

and white wires

module to

does pilot spark?

on the ignition

incoming ground?

Check for 24V

YES

control module

YES

NO

(ICM)

YES

Repair

between PV &

Does pilot light?

YES

PV/MV terminals

YES

Ground

on gas valve

NO

Check for 24V

Replace

NO

Does sparking

YES

between PV &

Check for 24V

stop?

MV/PV terminals

between orange

YES

gas

ignition control

& white wires on

valve

NO

Replace

module (ICM)

damper harness

Check for 24V

Clean flame

YES

NO

ICM

Bypass

between PV &

sensor - check

Check spark wire

damper,

PV/MV terminals

ground. If still

ignition control

problem,

FOUND

for damage &

ALL

orange & purple

module (ICM)

see below

continuity. Also

wires, if heater

NO

YES

DAMAGE

check spark

OK

fires then

assembly for

replace

cracks in ceramic

damper

Replace

Bad spark

or wrong spark

ICM

gap

Go to

assembly or

Replace

Replace

wiring between

thermostat

spark assembly

faulty

ICM

troubleshooting

OK

Check gas supply

& ICM

component

flow chart

Does main

NO

Is there 24V

NO

Is there 24V

NO

Repair

burner fire?

between MV &

between MV &

gas

PV/MV terminals

PV/MV terminals

supply

YES

at gas valve?

at the ICM?

YES

Does

Replace

ALL

Check for

YES

main burner

ICM

SHOULD

stay lit until

blockage in

BE OK

thermostat

burner or orifice,

NO

satisfies?

also check

NO

incoming gas

supply

Go to

Does pilot light

YES

Is gas flex being

Check &

NO

shrink or go out

NO

thermostat

used, or other

adjust gas

when main

troubleshooting

small pipe?

burner fires?

pressure

flow chart

Replace

OK

gas

valve

FCG3-0805 Copyright© by American Water Heater Company 2005. All rights reserved.