Mueller E-Star OESE 7.5 and 9 HP HFC Condensing Unit
Installation and Operation Manual, Part No. 8828748
Effective June 16, 2020
3.1
EPA REFRIGERANT REGULATIONS
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Mueller OESE condensing units are designed to operate with R-507 refrigerant. R-507 refrigerant is specified by
ASHRAE Standard 34 Safety Classification as an “A-1” refrigerant with low flame propagation and low toxicity.
EPA regulations require that any technician performing refrigerant installation or service on a high-pressure
appliance be certified as a Type II or Universal Technician in accordance with Section 608 of the Clean Air Act.
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As adopted for the United States and Canada. These regulations may change or differ for your locality. It is the responsibility of the
technician performing the refrigerant service and/or installation to abide by all regulatory requirements for the installation locality,
state, and country.
3.2
INITIAL REFRIGERANT CHARGE
IMPORTANT: Mueller E-Star condensing units must be triple evacuated to 500 microns before
refrigerant charging.
The most efficient and reliable method to charge the condensing unit is to weigh in the charge, ensuring it matches
the startup charge recommendation in Table 6. The refrigerant charge should be adjusted for the final operating
charge, as described in Section 3.4.
TABLE 6: RECOMMENDED STARTUP REFRIGERANT CHARGE
NOTE:
R-507 is recommended for use with Mueller E-Star OESE condensing units; however, other refrigerants
may be compatible. Contact the Mueller Dairy Farm Equipment Service Department for more information.
IMPORTANT: The compressor is equipped with Rotalock suction and discharge service valves intended
for ease of compressor change-out only. At no time during operation should these valves be closed.
3.3
WEIGH-IN REFRIGERANT CHARGING
The following steps will outline the procedure to weigh in the refrigerant startup charge:
1. With a clean and evacuated system, connect the manifold gauges to P2, suction charging access port, and P6,
high-side service valve.
2. Connect the center charging hose to a cylinder of new or reclaimed ARI 700-88 specifications refrigerant.
3. Weigh and record the gross weight of the refrigerant cylinder.
4. Purge any air from the manifold gauge hose as specified by EPA Section 608, de-minimus release.
5. Break the refrigeration system’s vacuum with liquid refrigerant, charging into the Schrader port at P2, suction
charging access port.
6
Section 3.0 – Refrigerant Charging
Recommended Startup Charge
Condensing Unit Size
Milk Cooler
Chiller
7.5 HP
25 lbs / 11.34 kg
23 lbs / 10.43 kg
9 HP
25 lbs / 11.34 kg
23 lbs / 10.43 kg