Helmer iB111 (Version A) - Change the Hysteresis Value; 18 Maintenance; Recharge Refrigerant

360077-1/O 85
Horizon Series™ - Blood Bank Models
17.6 Change the Hysteresis Value
► Default setpoint for is 4.0 °C
► Allowable temperature variance on each side of the refrigerator setpoint
NOTICE Hysteresis is factory-preset and should not be changed unless directed by Helmer
Technical Service.
18 Maintenance
NOTICE ► Before performing maintenance, protect items in refrigerator from extended exposure
to adverse temperature.
► Allow refrigerator temperature to stabilize at setpoint after performing service or after
extended door opening.
NOTE Refer to the operation manual for the preventive maintenance schedule.
18.1 Recharge Refrigerant
CAUTION ► Review all safety instructions prior to recharging refrigerant. Refer to chapter 2
(Safety).
► Maintenance should only be performed by trained refrigeration technicians.
NOTICE Use only non-CFC R-134A refrigerant.
Full initial refrigerant charge varies by model and power requirements, which can be found on the product
specicationlabel.
Model Voltage Initial Charge
111 Any 7.5 oz. (213 g)
120/125 Any 10.0 oz. (283 g)
245/256
115 V, 60 Hz Contact Helmer Technical Service
230 V, 50/60 Hz 20.0 oz. (567 g)
Obtain:
► Refrigerant
► Calibrated pressure gauge (0 psi to 25 psi (0 kPa to 175 kPa))
Add refrigerant:
1 Attachpressuregaugetothettingsontherefrigerationlines.
2 Monitor the low side (suction) pressure through a full compressor cycle.
3 Measure the pressure at the end of the next cycle, immediately before the compressor stops.
NOTE Pressure varies depending on ambient air temperature.
4 Add refrigerant. Check the pressure on the low side.
► Low side = 16 psi to 18 psi (110 kPa to 125 kPa)
5 Remove pressure gauge.