Operation manual
12
RKHBH/X016AB
Indoor unit for air to water heat pump system and options
4PW50206-1A
[3] Auto restart
When power returns after a power supply failure, the auto restart
function reapplies the user interface settings at the time of the power
supply failure.
Note that with the function disabled the schedule timer will not be
activated when power returns to the unit after a power supply failure.
Press the
pr
button to enable the schedule timer again.
■
[3-00] Status: defines whether the auto restart function is
turned
ON (0)
or
OFF (1)
.
[4] Backup heater operation and space heating off temperature
Backup heater operation
The operation of the backup heater can altogether be enabled or
disabled, or it can be disabled depending on operation of the booster
heater.
■
[4-00] Status: defines whether backup heater operation is
enabled (1) or disabled (0).
■
[4-01] Priority: defines whether backup heater and booster
heater can operate simultaneously (0), or if the booster
heater operation has priority over the backup heater
operation (1), or if the backup heater operation has priority
over the booster heater operation (2).
Space heating off temperature
■
[4-02] Space heating off temperature: outdoor temperature
above which space heating is turned off, to avoid
overheating.
■
[4-03] Booster heater operation: defines whether the optional
booster heater operation is enabled (1) or limited (0).
[5]
Equilibrium temperature and space heating priority
temperature
Equilibrium temperature
— The 'equilibrium temperature' field
settings apply to operation of the
backup heater
.
When the equilibrium temperature function is enabled, operation of
the backup heater is restricted to low outdoor temperatures, i.e. when
the outdoor temperature equals or drops below the specified
equilibrium temperature. When the function is disabled, operation of
the backup heater is possible at all outdoor temperatures. Enabling
this function reduces the working time of the backup heater.
■
[5-00] Equilibrium temperature status: specifies whether the
equilibrium temperature function is enabled (1) or
disabled (0).
■
[5-01] Equilibrium temperature: outdoor temperature below
which operation of the backup heater is allowed.
Space heating priority temperature
—
Applies only to installations
with a domestic hot water tank.
—
The 'space heating priority
temperature' field settings apply to operation of the 3-way valve and
the
booster heater
in the domestic hot water tank.
When the space heating priority function is enabled, it is assured that
the full capacity of the heat pump is used for space heating only
when the outdoor temperature equals or drops below the specified
space heating priority temperature, i.e. low outdoor temperature. In
this case the domestic water will only be heated by the booster
heater.
■
[5-02] Space heating priority status: specifies whether space
heating priority is enabled (1) or disabled (0).
■
[5-03] Space heating priority temperature: outdoor
temperature below which the domestic water will be heated
by the booster heater only, i.e. low outdoor temperature.
■
[5-04] Set point correction for domestic hot water
temperature: set point correction for the desired domestic hot
water temperature, to be applied at low outdoor temperature
when space heating priority is enabled. The corrected
(higher) set point will make sure that the
total
heat capacity of
the water in the tank remains approximately unchanged, by
compensating for the colder bottom water layer of the tank
(because the heat exchanger coil is not operational) with a
warmer top layer.
NOTE
It is therefore recommended to leave the auto restart
function enabled.
NOTE
If the benefit kWh rate power supply is of the type that
power supply is interrupted, then always allow the auto
restart function.
NOTE
When the priority field setting is set to ON (1),
space heating performance of the system
might be decreased at low outdoor
temperatures, since in case of domestic water
heating demand the backup heater will not be
available for space heating (space heating will
still be provided by the heat pump).
When the priority field setting is set to ON (2),
domestic water heating performance of the
system might be decreased at low outdoor
temperatures, since in case of space heating
demand the booster heater will not be
available for domestic water heating. However
domestic water heating by heat pump will still
be available.
When the priority field setting is set to OFF (0),
make sure that electrical power consumption
does not exceed supply limits.
NOTE
If the booster heater operation is limited, then
the booster heater operation is only allowed
during the disinfection function [2] (refer to
"[2]
Disinfection function" on page
11.) or
when powerful domestic hot water temperature
is initiated.
NOTE
If the booster heater operation is limited ([4-03]=0)
and the ambient outdoor temperature
T
A
is lower
than the field setting to which parameter [5-03] is
set, then the domestic water will not be heated.
T
set
Domestic hot water set point temperature
T
U
User set point (as set on the user interface)
T
A
Ambient (outdoor) temperature
Space heating priority
T
A
T
set
T
U
[5-03]
[5-04]
