State Industries SBD85 500 Test High Limit Right Terminal, High Limit ECO, Temperature, Adj. Dial

SBD TANK TYPE HEATERS

SERVICE HANDBOOK

STEP 3

TEST HIGH LIMIT RIGHT TERMINAL

High Limit (ECO)

Temperature

Reset Button

Adj. Dial

	High
Black-To	Limit/Thermostat
Damper Motor	Jumper Wire

STEP 3. TO TEST HIGH LIMIT RIGHT TERMINAL. Ensure that the jumper wire between the high limit and thermostat is connected, and the damper motor power line is connected. Test for 24 VAC between the high limit right terminal and ground.

IF	THEN
The meter does not read 24 VAC:	•	Push the reset button and redo the test (storage
		water temperature below 185 degrees).
The meter reads 24 VAC:	•	Go to step 4.
After Push in Reset - 24 VAC is now present

Reasons For Resetting

Condition	Cause	Solution
High limit open	Never set on initial	Push high limit button
	installation
Excessive water temperature	Faulty thermostat	Replace dual control
Heater shut down before	Faulty high limit	Replace dual control
reaching thermostat setting

Note: The right terminal of the high limit has a jumper wire connected to the left terminal of the thermostat. There is also a black wire connecting to the damper motor assembly. This black wire supplies power to the motor to close the damper during periods of standby.

Technical Training Department	21
Ashland City, TN ©2003