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AZ6500
When an AZ6500 Zoneline is in the heating mode,
the resistance heater or the compressor runs with
the appropriate fans. The control shall be capable
of independently switching power for two resistance
heater loads. Each of the two heater loads can
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elements will be tied together in parallel. There
are three stages of operation associated with the
heating mode:
• Stage
1: Heating due to heat pump (compressor)
- both fans on.
• Stage
2: Heating due to heat pump (compressor)
and supplemental 1000 Watt resistance heater
(Heater A) with both fans on. (This mode can also
be activated via aux set mode to run in place of
stage 1 heating). This auxiliary setting is known
as Boost Heat, and essentially disables stage
1 heating which is replaced by stage 2 heating.
When this mode is active, it will run when the
Zoneline is being controlled via the Zoneline
control panel, or when a remote wall thermostat
is connected and calling for heat pump. It will
override stage 1 heating in both cases. *NOTE:
Any time the Zoneline enters stage 2 heating
mode, it should continue heating in this mode
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be engaged.
• Stage
3: Heating due to resistance heater
(Heater A, B and C) - indoor fan only on.
NOTE: Any time the Zoneline enters stage 3 heating
mode, it will continue heating in this mode until the
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conditions. The Zoneline can then resume normal
heating operation modes of stage 1 or stage 2
heating upon the next call for heat.
NOTE: In low fan speed, the Zoneline shall only
activate heater A and B to allow for a maximum
heater output of 3800 W. A, B, and C output is only
available in high speed. Heat Pump Mode and
Heater B shall never be on at the same time.
Upon initial start-up or resumption after a power
interruption, stage 3 (Heater A and Heater B) are
energized at full power to generate heat until the
room temperature rises to the temperature setting,
regardless of the outdoor temperature.
Automatic changeover between the compressor
and the heating elements is utilized.
In order to keep the compressor from stalling out
when trying to start against the high side refrigerant
pressure, the control circuit has a built-in automatic
time delay to allow the internal pressure to equalize.
The control circuit will not try to start the compressor
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compressor cycling, the control has a built-in
minimum compressor run time of 3 minutes (+/- 10
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indoor temperature is dropping, the compressor will
run for a minimum of 3 minutes. The Zoneline can
switch to stage 2 heating, but must wait until the 3
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switching to stage 3 heating.
• FIRST STAGE HEAT (HEAT PUMP ONLY)
Once heating initializes, the room temperature
will start to rise. The compressor will run
until the temperature rises 0.9°F above the
temperature control set point, at which time
the compressor will shut down. If the outdoor
ambient temperature is less than 25°F, stage
1 heating will be disabled and only stage 3
heating will energize. This is also the case for
the remote wall thermostat. When the outdoor
ambient temperature is greater than 46°F, the
Zoneline runs at First Heat (Heat Pump).
• SECOND STAGE HEAT (HEAT PUMP + HEAT A) -
Boost Heat mode
When either the room temperature falls from
the setting by greater than 1.8°F, or the outdoor
temperature is lower than 25°F, stage 2 heating
will be disable and only stage 3 heating will
energize.
If the outdoor temperature is above 25°F, the
control will energize stage 2 heating. Stage 2
heating will continue to operate until the room
temperature exceeds the temperature control
set point by 0.9°F, at which time the heater and
the compressor will stop.
NOTE: Second stage heat is not utilized in class 2
mode. Unless aux set "boost heat" is selected. Stage
2 heating will operate when the thermostat calls for
stage 1 heating.
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