State Industries STC-074 Water Heater User Manual


 
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Technical Training Department ©2003
Ashland City, Tennessee
SBN TANK TYPE COMMERCIAL GAS WATER HEATER
SERVICE HANDBOOK
TEST 6 - INDUCER ON-NO IGNITION
Conditions:
Power on
Plugs in receptacles
Inducer operating
No power to Hot Surface Igniter (HSI)
Note flash code of LED
TEST 6
24 VAC Check of Blower Prover/Low Gas Pressure Circuit
Draft Proving Pressure
Switch
Exhaust
Outlet
Optional Hot
Water Outlet
Inducer
Draft Exhaust
Low Gas
Pressure
Switch
If… ...then
igntion board receptacles E1, Pin 7 to ground
show s
no voltage
replace Ignition board
E1, Pin 7
has 24 Volt
to ground check wire connection to and from inducer
voltage check of each blower switch terminal to
ground
show s voltage
to only 1 terminal
switch is open - check for proper draft (should
also see LED 3 flash code)
check for blocked exhaust
check that blower outlet exhaust damper is open
replace blower (draft) proving switch
24V
is present
from each switch terminal to ground.
check wiring from blower switch to low gas
pressure switch
voltage check to each terminal of low gas pressure
switch and ground
shows only voltage on 1
terminal
switch is open - test for a minimum of 5.2 ± "
W.C. Natural Gas or 10.5" Propane, flowing
supply gas pressure (should also see 3 Flash
LED code)
replace low gas pressure switch
voltage
is present
to each pressure switch terminal
and ground
check wiring from low gas pressure switch to
ignition board recetacles E1, Pin 10