[6] DT for domestic water heating
Applies only to installations with a domestic hot water tank.
The 'DT (delta temperature) for domestic water heating' field settings
determine the temperatures at which heating of the domestic water
by the heat pump will be started (i.e., the heat pump ON
temperature) and stopped (i.e., the heat pump OFF temperature).
When the domestic hot water temperature drops below the heat
pump ON temperature (
), heating of the domestic hot water by
T
HP ON
the heat pump will be started. As soon as the domestic hot water
temperature reaches the heat pump OFF temperature (
the user set point temperature (
T
the heat pump will be stopped (by switching the 3-way valve).
The heat pump OFF temperature, and the heat pump ON
temperature, and its relation with field settings [6-00] and [6-01] are
explained in the illustration below.
[6-00] Start: temperature difference determining the heat
pump ON temperature (
[6-01] Stop: temperature difference determining the heat
pump OFF temperature (
T
> T
U
HP MAX
T
= 70°C
U
T(°C)
[6-01] =
7°C
[6-00] =
7°C
70
T
U
55
T
HP MAX
[6-01]
48
T
HP OFF
[6-00]
41
T
HP ON
T
User set point temperature (as set on the user interface)
U
T
Maximum heat pump temperature at sensor in domestic hot
HP MAX
water tank (55°C)
T
Heat pump OFF temperature
HP OFF
T
Heat pump ON temperature
HP ON
T
is a theoretical value. In reality the maximum
NOTE
HP MAX
tank temperature that can be reached with the heat
pump is 53°C. It is advised to select T
than 48°C in order to improve performance of the heat
pump during domestic water heating mode.
Installation manual
23
T
HP OFF
), heating of the domestic water by
U
). See illustration.
T
HP ON
). See illustration.
T
HP OFF
T
< T
U
HP MAX
T
= 45°C
U
T(°C)
[6-01] =
7°C
[6-00] =
7°C
55
T
HP MAX
45
T
= T
U
HP OFF
[6-00]
38
T
HP ON
not higher
HP OFF
[7] Domestic hot water step length
Applies only to installations with a domestic hot water tank.
When the domestic water is heated and the domestic hot water set
point temperature (as set by the user) has been reached, the booster
heater will continue to heat the domestic water to a temperature a
few degrees above the set point temperature, i.e. the booster heater
OFF temperature. These extra degrees are specified by the domestic
hot water step length field setting. Correct setting prevents the
booster heater from repeatedly turning on and off (i.e. chattering) to
) or
maintain the domestic hot water set point temperature. Note: the
booster heater will turn back on when the domestic hot water
temperature drops 2°C (fixed value) below the booster heater OFF
temperature.
If the schedule timer for booster heater (see the
NOTE
operation manual) is active, the booster heater will only
operate if allowed by this schedule timer.
[7-00] Domestic hot water step length: temperature
difference above the domestic hot water set point
temperature before the booster heater is turned off.
T
DHW
T
73
BH OFF
T
71
BH ON
T
70
U
60
T
55
HP MAX
T
48
HP OFF
T
41
HP ON
40
30
20
HP
10
0
BH
Booster heater
HP
Heat pump. If heating up time by the heat pump takes too
long, auxiliary heating by the booster heater can take place
T
Booster heater OFF temperature (T
BH OFF
T
Booster heater ON temperature (T
BH ON
T
Maximum heat pump temperature at sensor in domestic hot
HP MAX
water tank
T
Heat pump OFF temperature (T
HP OFF
T
Heat pump ON temperature (T
HP ON
T
Domestic hot water temperature
DHW
T
User set point temperature (as set on the user interface)
U
t
Time
NOTE
If the booster heater operation is limited
([4-03]=0), then set point of field setting parameter
[7-00] has no meaning.
[7-00]
[6-01]
[6-00]
T
= 70°C
U
[7-00] =
3°C
BH
HP
[6-01] =
7°C
[6-00] =
7°C
+ [7-00])
U
– 2°C)
BH OFF
– [6-01])
HP MAX
– [6-00])
HP OFF
E(D/B)(H/L)Q011~016AA6V3+W1
Unit for air to water heat pump system
4PW51121-1A
t