Operation; User Tips; Defrosting; Maintenance - Isotherm DR 49 Mode D'emploi

2. Operation

The refrigerators are made for use at ambient tem-
parures between 0°C/32°F and +42°C/107°F.
2.1 Temperature regulation thermostat
The refrigerator is fi tted with a manually operated
thermostat. This is turned clockwise to reduce
temperature and anti-clockwise to both increase
temperature and activate the on-off switch at the end
position, 0-position. A certain spring resistance is
recognized at the off position.
It is advisable to start with the thermostat in a medium
position. It is advisable to keep a temperature of 5-6°C/
41-43°F inside the refrigerator. Higher temperatures
will reduce storage time.
The ambient temperature infl uences the temperature
also inside the fridge. Avoid direct sunshine and other
heat sources close to the refrigerator.
The thermostat control knob is placed inside the
refrigerator, see description below.

2.2 User tips

- Load the food inside the refrigerator in such a way, air
can circulate to equalize the temperature.
- Do not cover the shelves with glass or paper etc.
- To reduce the amount of ice building up in the
evaporator, cover all liquids and moist food.
- Let all hot foods cool well before putting them into the
refrigerator.

2.3 Defrosting

The evaporator is working on below freezing
temperatures and will form frost and ice from humidity
in the air. The humidity increases with higher outside
temperature, with storage of non sealed fresh food and
liquids and the time the door is kept open. Defrosting
shall be made when the frost layer is more than 4 mm
/ 1/8" thick.
Set the thermostat in OFF position or switch off on the
ASU control panel. Store the foodstuff and the liquid as
cold as possible during the defrosting process.
Do not use sharp metal tools to remove frost or
ice. Do not re-start until the refrigerator is completely
defrosted, cleaned and dried. Empty and clean also
the plastic drip tray below the evaporator. Place towels
in the bottom of the refrigerator to collect melt water.
3

3. Maintenance

The Isotherm DR refrigeration systems have a fully
hermetic closed cooling system and do not require any
maintenance or refi lling of refrigerant.
The compressor is of mobile type and has a very high
effi ciency and an outstanding life-time. The refrigerator
shall be left in the boat during the winter. (If the
temperature is below freezing point, the compressor
may not start). The maintenance is reduced to
periodically, not less than a year, cleaning of the
condenser from dust. Use a soft brush and no sharp
tools. Keep the cabinet inside clean. Use lukewarm
water and a mild detergent for cleaning the inside. Put
the doors, during not in operation periods, in their
slightly open ventilation position.

3.1 Battery voltage sensor

To protect the batteries from becoming completely
discharged, a battery voltage sensor switches off the
compressor automatically at the following levels:
Thermostat inside on
vertical wall.
If the bridge between C and P is cut off, values within
the () are valid.

4 Installation instructions

Many boats have a space which is intended for a
fridge. The Isotherm Cruise fridge has been designed
to suit the general dimensions normally used for this
purpose.
The compressor should normally stand upright in the
boat, but will operate at an angle of heel up to 30° and
for short periods even more.
The INOX type refrigerators have a fl ush mounting
frame, three side frame, as standard.

4.1 Ventilation

It is very important that the compressor/condenser
unit is well ventilated and that cold air can enter at the
bottom, pass behind the fridge and warm air can leave
at the top in the area where it is mounted. The natural
fl ow of air from below and upwards behind the fridge
can be increased by arranging ventilation openings at
the rear.
Make sure there is a free area of 100-150 cm² / 15
- 23 sq.in. below and behind the refrigerator to allow
ventilation air to pass behind from below.
See fi g.
System voltage V Cut out V
12 9.6 (10.4)
24 21.3 (22.8)
Cut in V
10.9 (11.7)
22.7 (24.2)