Enviromaster CHP, Nstallation, Operation And Maintenance Manual

Page: 20 / 28

E-mail: emi@enviromaster.com
Made in Rome, New York, USA
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COMMON TO ALL AIR HANDLERS - SEQUENCE OF OPERATION
Continued
OPTIONAL HEATPUMP WITH
ELECTRIC HEAT
(2-Stage Heating)
Important: The dip switch 1=OFF/Open
The dip switch 2=ON/2
For heat pump operation with backup electric heat, first
turn the unit on via the On/off button. Select Heat mode via
the Mode button. The room temperature will be displayed.
Then, by depressing either the Up or Down arrow once, the
setpoint temperature will appear. The setpoint temperature
can then be changed with each successive press of the Up
or Down arrow or by holding the button in.
Place the setpoint temperature one-degree above the
room temperature. The compressor will start and heating
will continue for a minimum of two minutes and as long as
the setpoint remains above room temperature. Once the
room temperature is satisfied and the two-minute minimum
run time has elapsed, the compressor will cycle off.
(*) On initial startup (or if power is lost) there is a three-
minute delay between compressor re-starts.
(**) Some EMI Heat pump condensers are equipped
with a low temperature cutout that will shut down the con-
denser and energize the indoor heat. This is designed to
protect the compressor under certain outdoor conditions.
(***) Some EMI Heat pump condensers energize the
indoor unit electric heat during defrost.
Next, place the setpoint temperature at least two
degrees above room temperature. The electric heat will
energize along with the compressor (heatpump) thus two-
stage heating. The electric heat will continue to run until the
deviation between room temperature and setpoint tempera-
ture is less than two degrees. At that time the electric heat
will switch off and the heatpump will take over the heating
demand. Once the room temperature is satisfied and the
two-minute minimum run time has elapsed, the compressor
will cycle off. There is then a three-minute delay before the
compressor can restart. The fan will operate as described
in “Fan Operation” ( Figure 5) .
DRY MODE OPERATION
Dry mode will remove humidity from the air while
maintaining a specific setpoint temperature. This is done
by energizing the compressor in cooling along with the elec-
tric or hydronic heater. Dry mode will not maintain a specific
humidity level. The unit must be equipped with an optional
electric heat element or hydronic coil.
For Dry Mode operation first turn the unit on via the On/
off button. Select Dry mode via the Mode button. The room
temperature will be displayed. Then by depressing either the
Up or Down arrow once, the setpoint temperature will appear.
The setpoint temperature can then be changed with each
successive press of the Up or Down arrow or by holding the
button in.
Place the setpoint temperature at a desired room tempera-
ture. Depending on the difference between room temperature
and set point temperature the compressor and/or heat source
will energize. If the room temperature and setpoint temperature
are the same the compressor will operate in cooling and the
electric heat source will also energize.
Should the room temperature fall below the setpoint
temperature by two degrees, the compressor will stop and
heating will continue to boost the room temperature back up
to stepoint temperature. If the room temperature rises above
the setpoint temperature by two degrees, heating will stop and
cooling will continue to bring the room temperature back down
to stepoint temperature. The fan will operate continuously at
low speed while in Dry Mode.
In order to prevent short cycling the minimum on time for
both cooling and heating is two minutes. The minimum off
time is 3 minutes ( Figure 5) .
OPTIONAL ELECTRIC HEAT OPERATION
(Non Heat Pump Condenser Units Only)
Important: The dip switch 1& 2 must be set to ON
For electric heat operation first turn the unit on via the
On/Off button. Select Heat mode via the Mode button. The
room temperature will be displayed. Then by depressing
either the Up or Down arrow once, the setpoint temperature
will appear. The setpoint temperature can then be changed
with each successive press of the Up or Down arrow or
by holding the button in. Place the setpoint temperature
above room temperature. The electric heat will energize
and heating will continue as long as the setpoint remains
above room temperature. Once the room temperature is
satisfied the electric heat will cycle off. The fan will operate
as described in “Fan Operation” ( Figure 5) .
UNITS WITH CONDENSATE PUMPS
EMI Air Handlers are available with an optional con-
densate pump. Condensate pumps are recommended
when it is not possible to gravity drain the condensation
from the indoor unit. Depending on the pump manufacture
the maximum lift for the pump will vary. Consult the pump
instructions for the maximum lift for the particular pump
being used or refer to specific pump kit information and
instructions as supplied by EMI.
Condensation generated by the evaporator will col-
lect in the pumps’ reservoir. When the water level is high
enough, a float switch will close and energize the pump
motor clearing the water from the reservoir. Should for
any reason the water exceed the maximum preset level,
a safety switch will open, there by interrupting the (Y) sig-
nal to the condenser. This will prevent the evaporator from
generating more condensation and spilling out of the unit.