Compressor Burn-Out - Bras FBM L-LS-UL Service Manual

system. Our refrigeration systems are manufactured so as to be
chargeable through the compressor process tube only (low
side): thus, the HI port is never mentioned nor used in the
following procedure and therefore the HI valve must be kept
closed.
1
Determine how many ounces/grams should be filled by the
charging unit. This information can be found on the dispenser
data plate.
2
Remove bowls and mixers from the dispenser.
3
Plug in the dispenser and turn on the power switch.
4
Set to I position all the Mixer/Refrigeration switches and
wait until solenoid valves are activated (in multiple bowl
machine only) and compressor starts.
5
Open the line valve of the charging unit.
6
Open the REF valve very slowly so as to allow the
refrigerant to be pulled into the system as a gas.
7
When the amount of refrigerant listed on the data plate has
been used, the system is charged. Close the REF valve and
the charging unit line valve and allow the compressor to run few
minutes.
8
Ensure that all evaporator cylinders are covered with frost.
9
Close the LOW valve, disconnect the LOW hose from the
compressor process tube and tighten the screw cap.
The following table reports the suction and discharge pressures
of the machines with the different refrigerants.
They must be verified under the following conditions:
Ambient temperature: 32 °C
Product temperature in the bowls: 0 °C
Evaporation temperature approx -5 °C
Condensation temperature approx 50°C.
Refrigerant Suction (low)
pressure
R134a 1,43 bar
R22 3,20 bar
R407 2,86 bar
R404a 4,10 bar

13. 3 COMPRESSOR BURN-OUT

To determine if a burn-out has occurred, perform the following
steps:
1
Disconnect the unit from power source.
2
Remove wiring from the compressor terminals.
3
Using an ohmmeter, check for ground between the
terminals and the compressor housing. If a reading exists, the
compressor has shorted to ground.
If a burn-out has occurred, compressor must be replaced as per
following steps:
4
Recover the refrigerant using an approved refrigeration
recovery system as per DISCHARGING instructions.
5
Remove the burned-out compressor.
6
Correct the system fault which caused the burn-out. Check
the condition of the capacitor(s) and compressor relay.
7
Install a new compressor and liquid line filter dryer.
8
Evacuate and charge the system as per EVACUATING and
CHARGING instructions.
Discharge (high)
pressure
12,17 bar
18,39 bar
21,10 bar
21,93 bar
19