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

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ELECTRONIC CONTROL SYSTEM
Servicing should only be performed by a Qualified Service Agent
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ELECTRONIC CONTROL SYSTEM
HEATING ELEMENT OPERATION
Depending on tank size and how they were ordered from the factory the water
heaters covered in this manual may be equipped with 1 to 5 electric heating
elements. See Heating Element Construction on page 16. The illustration here
shows how the heating elements are numbered and initially cycled on by the
control system - top to bottom. The illustration also shows how the openings for
each heating element are physically arranged on a water heater equipped with 5
heating elements.
Control Options
The water heaters covered in this manual are factory ordered with 1 of 3 different heating
element control options as follows:
Standard On/Off Control: This is the only configuration available on models equipped with
a single heating element and the standard configuration on models equipped with more than
one element. All elements are cycled on simultaneously with each call for heat, however
there is a one second delay between elements being energized to reduce starting current.
All elements are cycled off at the same time at the end of each heating cycle.
Optional Modulation Sequencing: Available on models equipped with more than one
heating element. First On/First Off cycling of heating elements - the first heating element
energized at the beginning of a heating cycle is the first element de-energized at the end of
the heating cycle. Elements are energized and de-energized according to adjustable (1 to
20°F) Differential set points for each element - see page 61. Element Rotation - the first
element energized is rotated with each successive heating cycle. Successive heating cycles
would progress as follows on a model equipped with 3 heating elements:
• First heating cycle: Elements come on [1, 2, 3] and cycle off [1, 2, 3].
• Second heating cycle: Elements come on [2, 3, 1] and cycle off [2, 3, 1].
• Third heating cycle: Elements come on: [3, 1, 2] and cycle off [3, 1, 2].
• Fourth heating cycle: pattern repeats - same as first.
Optional Linear Sequencing: Available on models equipped with more than one heating
element. Operation is the same as Modulation Sequencing described above except that the
“First” heating element energized will be the “Last” element de-energized during operation.
IE: First On/Last Off cycling of heating elements. Successive heating cycles would progress
as follows on a model equipped with 3 heating elements:
• First heating cycle: Elements come on [1, 2, 3] and cycle off [3, 2, 1].
• Second heating cycle: Elements come on [2, 3, 1] and cycle off [1, 3, 2].
• Third heating cycle: Elements come on: [3, 1, 2] and cycle off [2, 1, 3].
• Fourth heating cycle: pattern repeats - same as first.