Bosch Compress 3000 DW FOO Installation Instructions Manual page 8

8 | Appliance details
Defrosting
During the heating, when the air temperature is between -7 °C
and 10 °C frost may be formed at the evaporator, thus blocking
the air flow and reducing the heat transfer efficiency.
To avoid this occuring, the appliance will automatically defrost
the evaporator by injecting hot refrigerant gas into the
evaporator circuit via a bypass valve. The control of this
functionality relies on the temperature readings of the air and
fins sensors.
The defrost cycles last typically between 5 and 15 minutes and
their frequency depends on the environmental conditions (air
temperature and relative humidity).
During the defrost cycles only the compressor runs. After the
evaporator defrost is concluded the unit returns to normal
operation.
In case the air flow is restraint, for instance due to high wind
intensity at the air outlet, the frequency of defrost cycles might
increase.
Working condition
The appliance is designed to operate with best efficiency when
the air temperature is between -7 °C and +40 °C.
Care should be taken to feed the unit only with potable water
( section 4.8.1). Do not use untreated water from lakes,
rivers or groundwater!
Overheating protection
In case the water temperature near the electrical heating
element reaches 84 4 °C the power to the electrical element
is cut off by a thermostat mounted together with the electrical
heater and will require a manual reset.
Water temperature and pressure protection
The unit is supplied with a PTR valve for your safety (supplied
accessory). If the tank pressure reaches 1000kPa or the
temperature reaches 99 °C, the PTR valve will open
automatically to allow the pressure or temperature to decrease
to safe values.
The warranty can become void if relief valves or other safety
devices are tampered with or if the installation is not in
accordance with the instructions in this manual.
Mains Pressure
This water heater is designed for direct connection to mains
water supply. In case the mains supply pressure exceeds
800kPa, a pressure limiting valve must be installed
(section 4.4.6). A minimum water supply pressure of
200kPa is required to assure the effective operation of this
water heater.
6 720 808 869 (2014/06) Compress 3000 DW FOO