Carrier Aquasnap 30RB 160R User Manual

8.5.1 - Hydraulic circuit cleaning procedure
Before proceeding, it is advisable to remove any possible
contamination from the hydraulic circuit.
• Start up the unit pump by using the override command.
• Set the frequency to the maximum value to generate a
higher ow rate.
• If there is a ‘‘Maximum fow exceeded’’ alarm, reduce the
frequency until an acceptable value is reached.
• Read the value of the ow on the user interface.
• Let the pump run for 2 hours continuously to ush the
system's hydraulic circuit (presence of contaminating
solids).
• Perform another reading of the ow and compare this value
with the initial value. A reducing value of the ow indicates
that the lters on the system need to be removed and
cleaned. In this case, close the shut-o󰀨 valves on the water
inlet and outlet (item 19) and remove the lters (items 12
and 1) after draining the hydraulic part of the unit (item 6).
• Remove the air from the circuit (items 5 and 14).
• Repeat until all fouling is removed from the lter.
8.5.2 - Procedure for controlling the pressure
di󰀨erential
Setpoint
Once the circuit is cleaned, place the hydraulic circuit in the
conguration for which the unit selection was performed generally
(all valves open and all cooling coils active). Read the value of
the !ow on the user interface and compare it with the theoretical
value of the range:
• If the value of the ow is greater than the specied value,
reduce the pressure differential setpoint on the user
interface to reduce the value of the ow.
• If the value of the ow is lower to the specied value,
increase the pressure di󰀨erential setpoint on the user
interface to increase the value of the ow.
Repeat until the design pressure drop / ow rate is achieved.
Stop the forced operation of the pump and proceed to the
conguration of the unit for the required control mode.
Modify the control parameters:
- Set water ow control to ‘pressure di󰀨erential’
- Set the value of the required di󰀨erential pressure
By default, the unit is factory congured at the minimum speed
(frequency: 50 Hz).
NOTES:
If during controlling, the low or high frequency limits are
reached before reaching the specied ow, keep the pressure
di󰀨erential value to its lower or higher limit to enter in the
control parameters.
If the user already knows the pressure di󰀨erential value to
be maintained at the unit outlet, this may be entered directly
as a parameter. However, the hydraulic circuit cleaning
sequence must not be omitted.
8.6 - Units with hydraulic module and variable-
speed pump - temperature di󰀨erence control
The temperature sensors at the heat exchanger inlet and outlet
(items 8 and 9 in the typical hydraulic circuit diagram) are used
as means of control.
The system reads the measured temperature values, calculates
the corresponding temperature di󰀨erence, compares it with the
user-selected setpoint value and modulates the pump speed as
necessary:
• If a higher delta T value than the set point is measured, the
ow rate is increased.
• If a lower delta T value than the set point is measured, the ow
rate is decreased.
This ow rate variation is realised, observing the minimum and
maximum admissible unit ow rates as well as the minimum and
maximum pump supply frequency values.
The delta T value maintained can in certain cases be di󰀨erent from
the set point value:
• If the set point value is too high (achieved for a lower ow rate
than the minimum value or a lower frequency than the
minimum value), the system settles at the minimum ow rate
or minimum frequency and this results in a lower delta T value
than the set point.
• If the set point value is too low (achieved for a higher ow rate
that the maximum value or a higher frequency than the
maximum value), the system settles at the maximum ow rate
or maximum frequency and this results in a higher delta T
value than the set point.
Contact Carrier Service to discuss the implementation of the
procedures set out below.
8.6.1 - Hydraulic circuit cleaning procedure
Refer to the procedure for cleaning the hydraulic circuit from chapter
8.3.1
8.6.2 - Procedure for adjusting the Delta T° setpoint
Once the circuit is cleaned, stop the forced start of the pump and
proceed to the conguration of the unit for the required control mode.
Modify the control parameters:
- Water ow rate control method (temperature di󰀨erential)
- Set the value of the required di󰀨erential temperature.
By default, the unit is factory congured at the minimum speed
(frequency: 50 Hz).
Combination of options for the periods when the unit is in
standby mode.
Ambient unit
temperature range
Product
without
option 116
With option
116
With option
307
> 0 °C to 51 °C - -
-20 °C to 0 °C
Option 41
or
Suitable
antifreeze
solution (such
as glycol)
Option 42
(1)
or
Suitable
antifreeze
solution (such
as glycol)
(1)
Option 42B
(1)
or
Suitable
antifreeze
solution (such
as glycol)
(1)
(1) Allow the pumps to circulate. If there is a valve, install a bypass (see diagram
for winter position).
8 - WATER CONNECTIONS
29

Carrier Aquasnap 30RB 160R Specifications

General

Brand	Carrier
Model	Aquasnap 30RB 160R
Category	Chiller
Language	English