360077-1/O
116
Horizon Series™ - Laboratory, Pharmacy, and International Blood Bank Models
25 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.
25.1
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
specification 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 fittings 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.