SBN TANK TYPE COMMERCIAL GAS WATER HEATER

SERVICE HANDBOOK

TEST 6 - INDUCER ON-NO IGNITION

Conditions:

ƒPower on

ƒPlugs in receptacles

ƒInducer operating

ƒNo power to Hot Surface Igniter (HSI)

ƒNote flash code of LED

Draft Proving Pressure

Switch

Optional Hot

Water Outlet

Low Gas

Pressure

Switch

Draft Exhaust

Exhaust

Outlet

Inducer

TEST 6

24 VAC Check of Blower Prover/Low Gas Pressure Circuit

If…

 

...then

 

igntion board receptacles E1, Pin 7 to ground shows

 

replace Ignition board

 

no voltage

 

 

 

E1, Pin 7 has 24 Volt to ground

 

check wire connection to and from inducer

 

voltage check of each blower switch terminal to

 

switch is open - check for proper draft (should

ground shows voltage to only 1 terminal

 

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 is open - test for a minimum of 5.2 ± "

switch and ground shows only voltage on 1

 

W.C. Natural Gas or 10.5" Propane, flowing

 

terminal

 

supply gas pressure (should also see 3 Flash

 

 

LED code)

 

 

 

replace low gas pressure switch

 

voltage is present to each pressure switch terminal

 

check wiring from low gas pressure switch to

and ground

 

ignition board recetacles E1, Pin 10

 

Technical Training Department

31

©2003

 

 

Ashland City, Tennessee

Page 32
Image 32
State Industries STC-074 specifications Test 6 Inducer ON-NO Ignition, VAC Check of Blower Prover/Low Gas Pressure Circuit