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

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OPERATION & SERVICE
Servicing should only be performed by a Qualified Service Agent
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ELEMENT SENSORS
The water heaters covered in this manual monitor heating elements using Element Sensors.
Each Element Sensor monitors all the three loops of a heating element - see pages 16 & 17.
There will be one Element Sensor for each heating element. IE: water heaters equipped with
5 heating elements will have 5 Element Sensors.
Element Sensor Construction
Element Sensors are an assembly that consists of 3 individual current sensors, a 10
conductor plug and 9 wires that connect between the individual current sensors and the
plug. Each current sensor monitors one loop on a heating element. Current sensors are
enclosed in a black plastic housing that has a hole in the middle. One of the power wires to
each heating element loop is routed through the hole in one of the current sensors. See the
images below.
Element Sensor Functions
Working with the Element Sensors the electronic control system provides valuable
operational and diagnostic information to aid in servicing.
The electronic control system displays animated Status Icons on the UIM’s (User Interface
Module) LCD display to indicate which heating elements are being energized and which
heating elements are not being energized. The Status Icons will also indicate when a
heating element that has been commanded on (energized) by the control system is not
drawing current/amps. See the Desktop Screen on page 58 and the Status Icons Table on
page 59.
The electronic control system displays a “No Current Detected” Alert message on the UIM
(see pages 55 - 58 and 76) if the control system does not sense current (amperage) from a
heating element when expected. IE: a call for heat is active, the control system has
commanded all heating elements on - all contactor coils have been energized and the
control system is not sensing current from one or more heating element loops.
During Alert conditions the control system allows the water heater to continue heating (other
elements may still be working) but prompts the user to have the water heater serviced.
10 Conductor Plug Element Sensor
Three Current
Sensors