Carrier SmartView - Pumps Control and Configuration

6.4 - Supplementary heating
30RBM/RBP units may be tted with a boiler that allows the unit
to run in heating mode if required. The boiler is active only when
the unit is in Heating mode.
30RQM/RQP heat pumps may be tted with a boiler or electric
heaters. The boiler is used as heating replacement when
mechanical heating is not possible due to low outside air
temperature. Electric heaters can be turned on to satisfy the
heating demand when mechanical heating is insufcient.
6.4.1 - Boiler control
Boiler is activated when the outside air temperature is below the
user-congured boiler outdoor temperature threshold which is by
default set to -10°C (14°F).
To set boiler OAT threshold
1. Navigate to the Conguration menu.
2. Select Backup Conguration (BACKUP).
3. Set Boiler OAT Threshold [boil_th].
Boiler OAT Threshold [boil_th]
-15 to 15°C -10°C
5 to 59°F 14°F
6.4.2 - Electric heating control
Electric heating stages can be activated as additional heating
when OAT is below the user-congured electric heating OAT
threshold which is by default set to 5°C (41°F).
Electric heating is allowed when:
■ Unit is running at 100% capacity.
■ Electric pull-down time elapsed [ehs_pull].
■ OAT is below the OAT threshold [ehs_th].
There are four electric heating stages, where the last electric
heating stage is used for back-up when the unit is down due to
a detected fault.
To set electric heating OAT threshold
1. Navigate to the Conguration menu.
2. Select Backup Conguration (BACKUP).
3. Set Elec Stage OAT Threshold [ehs_th].
Elec Stage OAT Threshold [ehs_th]
-5 to 21°C 5°C
23 to 70°F 41°F
IMPORTANT: Electric heating is not allowed when the demand
limit is active on the unit.
6.5 - Pumps control
The control system can manage one or two water exchanger
pumps, determining each pump on/off state and its speed. Both
pumps cannot run together. The pump is turned on when this
option is congured and when the unit is running.
The pump is turned off when the unit is shut down due to an alarm,
unless the fault is a frost protection error. The pump can be started
in particular operating conditions when the water exchanger heater
is active.
If the pump has failed and another pump is available, the unit is
stopped and started again with the second pump. If there is no
pump available, the unit shuts down.
Conguration options may differ depending on the number and
type of pumps available (single speed pumps or variable speed
pumps).
6.5.1 - Variable speed pumps control
30RBM/30RBP chillers and 30RQM/RQP heat pumps may be
tted with one or two variable speed pumps.
Variable speed pumps give the possibility of saving the pumping
energy cost, providing precise water ow control and improving
the overall performance of the system. The frequency inverter
continuously regulates the ow rate to minimise the pump power
consumption at full load and part load.
Water ow management methods are as follows:
■ Fixed speed control (the control ensures a constant pump speed
based on compressor capacity).
■ Water ow control based on constant water delta pressure
(the control continuously acts on the pump speed to ensure
a constant delta pressure).
■ Water ow control based on constant delta T on the water
exchanger.
Fixed speed pumps can be either low or high pressure,
whereas variable speed pumps are always high pressure
pumps.
IMPORTANT: Units with customer pump may have only one
variable speed pump, whereas units with internal pumps may
have one or two variable speed pumps.
6.5.2 - Pumps conguration
The control can command internal xed speed or variable speed
pumps as well as customer pumps. Variable speed pumps may
also be congured as xed speed pumps (see also section 6.5.1).
Basic pump conguration can be performed via the Conguration
menu (PUMPCONF – Pump Conguration). Only logged-in users
can access the menu. The unit must be stopped.
IMPORTANT: Pump speed conguration can be performed
only by Carrier service.
To set pumps sequence
1. Navigate to the Conguration menu.
2. Select Pump Conguration (PUMPCONF).
3. Set Pumps Sequence [pump_seq].
Pumps Sequence [pump_seq]
0 No Pump
1 One Pump Only
2 Two Pumps Auto
3 Pump#1 Manual
4 Pump#2 Manual
6 - STANDARD CONTROL OPERATIONS AND OPTIONS
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