A.O. Smith DSE-5, Руководство по обслуживанию

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OPERATION & SERVICE
Servicing should only be performed by a Qualified Service Agent
30
Heating Element Ground Test
1 Secure power to the water heater at the main breaker or disconnect switch.
2 Verify with an AC volt meter that there is not any voltage present at the Power Distribution Block (see
Figure 2 on page 9) or the contactor on single element models.
3 Disconnect and label the power wires from the contactor(s) to all elements being tested. Pay close
attention to wiring and which heating element loops (see pages 16 & 17) connect to which terminals on the
contactor(s). Use wire markers (see Tools Required page 3) to label contactor terminals and/or the wiring
leads of the heating element to ensure they are reconnected properly when finished.
4 Using an ohm meter: set the ohm meter to one of it’s lowest resistance ranges - 200 ohms or less initially.
An audible beep continuity test setting can also be used on ohm meters so equipped.
Six Wire Elements: Test for continuity (ohms/resistance) between all six wire ends from each loop on the
heating element and the ground wire connection to the water heater - six continuity readings. See pages
16 & 17 and the illustrations below. There should not be any continuity between any wire and ground.
Three Wire Elements: Test for continuity (ohms/resistance) between all three wire ends of the heating
element and the ground wire connection to the water heater - three continuity readings. See pages 16 & 17
and the illustrations below. There should not be any continuity between any wire and ground.
The resistance in these tests should be infinite - no continuity to ground. If there is any resistance or
continuity measured between any element wire end and ground - the heating element is shorted to ground
and must be replaced - see page 31.
Checking a heating element for any resistance or
continuity to ground. Touch one of the ohm meter
probes to one wiring lead from a heating element
and the other probe to a grounded surface on the
water heater. Take additional continuity to ground
readings for all wiring leads on a heating element.
Testing a 3 Wire Element Testing a 6 Wire Element