Service Procedure RE-III

Residential Thermostat Testing

Single Element Operation or

Double Element, 4 Wire, Simultaneous, Single Phase Operation.

WARNING

High voltage exposure. Use caution to avoid

personal injury during this procedure.

Water In Tank Is Cold With Power ON.

1.This procedure assumes line voltage, ECO and elements are in working order.

2.Turn power “ON” to water heater.

3.Set multi-meter to “Volts AC”.

4.Check across terminals L4 and T2 of thermostat (see illustration 6).

A) Rated voltage NOT present,
Recheck ECO. If ECO is okay,
replace thermostat.
B) Rated voltage IS present,
proceed to next step.
5. Check across element terminals
(see illustration 7).
A) Rated voltage NOT present,	Illustration 6	Illustration 7
check wire connections from
thermostat to element.

	B) Rated voltage IS present,
	Repeat element testing
	see page 15.
	Water Temperature In Tank Is Above Thermostat Setting.
	1. This procedure assumes line voltage, ECO and
	elements are in working order.
	2. Turn power “ON” to water heater.
	3. Set multi-meter to “Volts AC”.
	4. See illustration 6 above, check across terminals L4 and T2
	of thermostat.
	A) Rated voltage IS present,
	replace thermostat.
	B) Rated voltage NOT present,
	thermostat is okay.	Reference 4 Wire, Simultaneous, Single Phase
	C) Lower than rated voltage IS present,	Reference 4 Wire, Simultaneous, Single Phase
	C) Lower than rated voltage IS present,	Wiring diagram.
	recheck for grounded element	Wiring diagram.
	(see page 15).	NOTE: Wiring consists of two single element configurations
		NOTE: Wiring consists of two single element configurations
		operating independently.

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