State Industries STC-074 Test 3 Continuity Check of High Limit ECO, Is indicated, Is not present

Page 30

SBN TANK TYPE COMMERCIAL GAS WATER HEATER

SERVICE HANDBOOK

TEST 3 - CONTINUITY CHECK OF HIGH LIMIT (ECO)-CONTINUED

TEST 3

Continuity check of ECO (energy cut-off, high limit)

Black to Black wires of upper probe. Power is off.

	If…		...then
	continuity	is indicated	opens at 203° F; closes at 193° F. If water is
	continuity	is indicated	below 193° F, continuity is correct.
			below 193° F, continuity is correct.
	continuity	is not present	replace ECO sensor, if water temperature is
	continuity	is not present	below 193° F.
			below 193° F.
			•reset status LED should be on.
	water is less than 120° F		•replace heater control if control will not manually
			reset.

TEST 4 - UPPER TEMPERATURE PROBE CONTINUITY CHECK

Conditions:

Power On - Water below tempera- ture set point.

Red, heater control “Reset Status”

LED-OFF

“Call For Heat” LED off.

Ohms Resistance Table

° F	Ohms
70°	11,884
120°	3,759
140°	2,488
180°	1,169

TEST 4

Upper Temperature probe continuity check

Red wire to red wire - Turn supply power "Off" for this test

If…	...then
test indicates no continuity	replace probe.
	probe should be okay (also verify Ohms
continuity is indicated	resistance for water temperature). (Reading will
	be approximate.)

Technical Training Department	29	©2003
	29

Ashland City, Tennessee

Image 30

Contents Service Handbook Table of Contents SBN Service Handbook Introduction Qualifications Custom Commercial Storage Tank Model Number Break DownInstallation Considerations Top and Front Views of Minimum Clearances To CombustiblesExterior Clearance Required Exterior ClearancesComb AIR Make-Up Air Direct Communication Not Direct Vent Make-Up Air Vertical Ducts Make-Up Air Horizontal DuctsContaminated Air Air for Combustion Flammable ItemsGas Valve Outlet View Venting Venting Atmospheric Multiple HeatersNine Rules for Good Vents SBN Tank Type Commercial GAS Water Heater Service Handbook SBN Tank Type Commercial GAS Water Heater Service Handbook Type B GAS Vent Multiple Gas Fired Tank-Type HeatersTechnical Dataventing Sequence Top ViewFront View of Water Heater SBN Tank Type Commercial GAS Water Heater Service Handbook HSI Integrated Ignition Control Board Lower Front View of SBN Water Heater HSIWiring Diagram ECOElectrical Sequence of SBN Water Heater Operation PRE-SERVICE Checklist Conditions Water Heater Control Ignition Control BoardFlash Codes of Diagnostic Indicator Test 2 Polarity CheckTest 2 Polarity Check Test 3 Continuity Check High Limit ECOIs indicated Test 4 Upper Temperature Probe Continuity CheckTest 3 Continuity Check of High Limit ECO Is not presentTest 5 Calling for Heat no Inducer Operation Water Heater ControlCheck to Inducer Test on Ignition Board 4 Pin Receptacle E4 Test 6 Inducer ON-NO Ignition VAC Check of Blower Prover/Low Gas Pressure CircuitVoltage is not present between E4, Pin Test 8 Igniter Heats no Main Burner Test of Igniter and gas valve circuitTest 9 Igniter Heats no Main Burner Continuity Check Of Gas Valve CoilTest 10 Main Burner Ignition for Less than 5 Seconds Flame Prover Circuit CheckTest 11 Water Heater Shutting OFF below Setting If… ThenDisplay Lights on Integrated Heater Control ECO SBN Tank Type Commercial GAS Water Heater Service Handbook Technical Training Department 120 154 180 199 200A 250A 275A 310A 366A 400A General Questions and Answers SBN Tank Type Commercial GAS Water Heater Service Handbook Draft Proving Pressure Switch Table