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

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Servicing should only be performed by a Qualified Service Agent
45
OPERATION & SERVICE
Temperature Sensor DC Voltage Test
1 Ensure the main breaker or disconnect switch is turned on.
2 Verify the CCB has the correct input voltage at the J2 socket and is properly grounded - perform the
“Checking Power and Ground To The CCB” tests on page 54.
3 Unplug the J5 plug from the CCB (note: the control system will lock out and display “Temp Probe Open”
Fault message on the UIM when the J5 plug is removed - cycle power off and reinstall J5 plug when tests
are complete). Using a “DC” (direct current) volt meter check for DC voltage between pins 2 & 3 of the J5
socket as shown in the “DC Voltage To Temperature Sensor” image below.
• If the measured voltage is 5 VDC the sensor is powered correctly. If there is not 5 VDC call the toll
free Technical Support phone number listed on the back cover of this manual for further assistance.
ECO Continuity Test
1 Secure power to the water heater at the main breaker or disconnect switch.
2 Unplug the J5 plug from the CCB - see page 50 for location.
3 Ensure tank temperature is less than 100°F/38°C - dump water to lower tank temperature if necessary.
4 Using an ohm meter; set the Ohm meter to it’s lowest resistance range (< 200) or to an audible beep
continuity test setting if so equipped.
5 Touch the ohm meter probes between the two outside pins (red wires) of the J5 plug end as shown in the
“Checking ECO Switch Continuity” image below.
• If the ohm meter shows continuity (closed circuit) between the two outside pins (red wires) of the J5
plug end the ECO switch has reset properly. If the control system continues to lock out displaying
the “Energy Cut Out (ECO)” Fault message with continuity through the ECO present call the toll free
Technical Support phone number listed on the back cover of this manual for further assistance.
• If the ohm meter shows no continuity (open circuit) between the two outside pins (red wires) of the
J5 plug end and the tank temperature is known to be at or below 100°F/38°C - replace the
Immersion Temperature Probe. Secure power to the water heater and drain the water heater before
replacing the probe - follow the draining and filling instructions in the maintenance section of the
Instruction Manual that came with the water heater.
• If the control system continues to lock out displaying the “Energy Cut Out (ECO)” Fault message
and the water temperature inside the water heater is becoming excessive (at or above 202°F/94°C)
check contactors (pages 34 - 38) to ensure they are not stuck closed and check for voltage at all
heating elements (page 26) during standby mode. Check water system piping; ensure heat is not
being added by any other heating appliances or heat sources. If all these tests have been performed
and the control system continues to lock out displaying the “Energy Cut Out (ECO)” Fault message
call the toll free Technical Support phone number listed on the back cover of this manual for further
assistance.
Checking ECO Switch Continuity
DC Voltage To Temperature Sensor