Safety And Control Devices - Dimplex BWP 301 L Instructions D'installation Et D'utilisation

2.3

2.3 Safety and Control Devices

The HW HP has the following safety features:
High-pressure switch (HP)
The high-pressure switch protects the heat pump against imper-
missibly high operating pressure in the refrigerant circuit. In the
event of a fault, the pressure switch will switch the heat pump off.
The heat pump restarts automatically as soon as the pressure
once again drops in the refrigerant circuit.
Safety temperature limiter for heating element
(STL)
The STL protects the hot water system against impermissible
temperature increases.
The heating element switches off whenever the set switching
value (99 °C) is exceeded.
The heating element cannot be switched on again until the hot
water temperature has decreased to  90 °C and the reset but-
ton (illustration) on the STL is then pressed (this may only be
done by qualified personnel).
Device fuse
The HW HP is equipped with a separate fuse to ensure internal
device protection. This fine-wire fuse (1.25 A slow-acting) is lo-
cated in a "screw-type device" (can be screwed apart in the mid-
dle) which is located on the side of the internal electrical connec-
tions (in the area next to the X1 terminal strip).
The HW HP is equipped with the following regulation and control
devices:
Heating element temperature controller (TC)
The heating element temperature controller regulates the hot
water temperature during heating element operation. The maxi-
mum controller temperature is factory set to 65 °C (the controller
and the STL are installed together in a casing). Temperature set-
tings can be changed using a suitable tool (see illustration).
Changes to this setting may be carried out by qualified personnel
only!
E-4
In automatic operation (activated via the air temperature thermo-
stat), the water is heated by the heating element until the fixed-
setpoint (on the heat pump temperature controller) has been
reached. (in contrast to heat pump only operation, a smaller
amount of water is heated up to minimise the operation period of
the heating element) In the manually switched continuous oper-
ating mode, the hot water is heated until the set maximum tem-
perature of the heating element controller is reached. The heat-
ing element may optionally be controlled via an external switch
(see the Section 5.3 "Electrical Connection"). The water is again
heated until the set maximum temperature of the heating ele-
ment controller has been reached.
Heat pump temperature controller
Temperature control in the hot water cylinder and the regulation
for compressor operation is carried out by the temperature con-
troller. This controller measures the hot water temperature via a
sensor and controls it in relation to the set value. The desired
temperature level (setpoint) is set via the rotary knob on the con-
trol panel.
Air temperature thermostat
This thermostat sensor measures the HW HP temperature di-
rectly upstream of the evaporator (air inlet temperature). As soon
as the temperature sinks below the set value (8 ±1.5 °C, switch-
back value 3K), the domestic hot water preparation is automati-
cally switched from heat pump operation to heat element opera-
tion (automatic operation).