heatcraft-refrigeration-p h-im-79d User Manual
7
BOX TEMPERATURE CONTROL SETTINGS
• There is an on board room thermostat on the Beacon II board which can be adjusted
to the desired room temperature. The temperature differential is 2
to the desired room temperature. The temperature differential is 2
°
F.
Temperature Differential
When a system is in the cooling mode and the box setpoint is 35
When a system is in the cooling mode and the box setpoint is 35
°
F, the system will
continue to cool until the box temperature gets to 34
°
F. At this point the compressor will
pumpdown and shut off. The system will restart cooling when the box temperature has
risen to 36
risen to 36
°
F.
It is important to note that Beacon II has a minimum 2 minute “ON” time and a minimum
4 minute “OFF” time. This means that the system will run in the cooling mode a
minimum of 2 minutes even if the setpoint temperature is met. In applications where the
system is grossly oversized, the box temperature could go below the differential
temperature before the system cycles off.
4 minute “OFF” time. This means that the system will run in the cooling mode a
minimum of 2 minutes even if the setpoint temperature is met. In applications where the
system is grossly oversized, the box temperature could go below the differential
temperature before the system cycles off.
In the “OFF” cycle the system will be off for a minimum of 4 minutes even if the box
temperature goes above the differential temperature, before cooling will be restarted.
temperature goes above the differential temperature, before cooling will be restarted.
• The on board room thermostat is factory set at 35
°
F for Air Defrost systems and
-10
°
F for electric defrost system.
LEAK TESTING
After all lines are connected, the entire system must be leak tested. The complete system
should be pressurized to not more than 150 psig with refrigerant and dry nitrogen. The use
of an electronic type leak detector is highly recommended because of its greater sensitivity
to small leaks. As a further check it is recommended that this pressure be held for a
minimum of 12 hours and then rechecked. For a satisfactory installation, the system must
be leak tight.
should be pressurized to not more than 150 psig with refrigerant and dry nitrogen. The use
of an electronic type leak detector is highly recommended because of its greater sensitivity
to small leaks. As a further check it is recommended that this pressure be held for a
minimum of 12 hours and then rechecked. For a satisfactory installation, the system must
be leak tight.
REFRIGERANT CHARGING
Beacon II systems are shipped standard with a head master valve (Scroll compressor
models has a 100 Psi head master valve. All other models have a 180 Psi head master
valve.) The maximum system refrigerant capacity is the receiver capacity as listed in the
sales literature plus the liquid line capacity. Do not add more refrigerant to the system than
90% of the receiver capacity.
models has a 100 Psi head master valve. All other models have a 180 Psi head master
valve.) The maximum system refrigerant capacity is the receiver capacity as listed in the
sales literature plus the liquid line capacity. Do not add more refrigerant to the system than
90% of the receiver capacity.
Box Temp Control Settings