Refrigerant Charging

To troubleshoot:

1.Apply voltmeter across crankcase heater leads to see if heater voltage is on. Do not touch heater. Carefully feel area around crankcase heater; if warm, crankcase heater is functioning.

2.With power off and heater leads disconnected, check across leads with ohmmeter. Do not look for a specific re- sistance reading. Check for resistance or an open circuit, and change heater if an open circuit is detected.

Service Valves — The service valves in the outdoor unit come from the factory frontseated. This means the refrigerant charge is isolated from the line-set connection ports. To prevent damage to the valve, use a wet cloth or other accepted heat sink material on the valve before brazing.

The service valve cannot be field repaired, therefore, only a complete valve or valve stem seal and service port caps are available for replacement.

To prevent personal injury, wear safety glasses and gloves when handling refrigerant. Do not overcharge system — this can cause compressor flooding.

Service valves must be fully backseated to close service port. There is no Schrader valve at the service port, and failure to backseat the valve could result in loss of system charge or personal injury.

NOTE: Do not vent or depressurize unit refrigerant to atmo- sphere. Remove and recover refrigerant following accepted practices.

All units are shipped with the refrigerant charge listed on the nameplate. See indoor unit Installation Instructions for ad- ditional charge requirements.

NOTE: For 38HDF units only, charge to nameplate. See the indoor unit owner’s manual for any additional charge requirements.

Refer to Table 4 and consider the following when working with Puron® refrigerant:

•Puron refrigerant cylinders are rose colored.

•Recovery cylinder service pressure rating must be 400 psig, DOT (Department of Transportation) 4BA400 or DOT BW400.

•Puron systems should be charged with liquid refrigerant. Use a commercial type metering device in the manifold hose when charging into suction line with compressor operating.

•Manifold sets should be 700 psig high side and 180 psig low side with 550 psig low-side retard.

•Use hoses with 700 psig service pressure rating.

•Puron refrigerant, as with other HFCs, is only compatible with POE oils.

•Vacuum pumps will not remove moisture from oil.

•Polyol Ester oils absorb moisture rapidly. Do not expose oil to atmosphere.

•Polyol Ester oils may cause damage to certain plastics and roofing materials.

•Wrap all filter driers and service valves with wet cloth when brazing.

•A factory approved, liquid-line filter drier is required on every unit.

•Do not use a TXV (thermostatic expansion valve) designed for use with R-22 refrigerant. Refer to separate indoor unit installation instructions for more details.

•If using a suction line drier, do not leave in place for more than 72 hours.

38HDR018-060, 38HDF018-036 specifications

Carrier is a renowned name in HVAC technology, and their 38HDR018-060 and 38HDF018-036 models showcase the fine craftsmanship and innovation typical of the brand. These rooftop units are designed to deliver reliable heating and cooling solutions, making them an ideal choice for commercial spaces and industrial applications.

One of the main features of the Carrier 38HDR and 38HDF series is their ability to provide efficient climate control. The units are equipped with high-efficiency scroll compressors, which ensure reduced energy consumption while maintaining optimal performance. This efficiency translates into significant cost savings on energy bills, making these units an environmentally conscious choice as well.

In terms of design, the 38HDR and 38HDF models boast a rugged construction that can withstand various weather conditions. They are built with a galvanized steel cabinet that resists corrosion, ensuring durability and longevity. The compact design of these rooftop units allows for easy installation and integration into existing structures, offering flexibility for building owners and operators.

Advanced technology is at the heart of these Carrier units. The inclusion of a microprocessor-based control system enables precise temperature management and system monitoring. This technology not only optimizes performance but also provides valuable data for maintenance planning, ultimately reducing the risk of unexpected failures.

The units also come with variable air volume capabilities, which enhances comfort by allowing for customizable airflow to meet specific environmental needs. The 38HDR and 38HDF series is designed to be compatible with multiple zoning systems, allowing facilities to better adapt to changing occupancy and usage patterns.

With sound levels minimized through advanced acoustic engineering, these rooftop units operate quietly, ensuring minimal disruption to occupants. This is especially important in commercial settings, where a peaceful environment is crucial to productivity.

Moreover, both series support enhanced indoor air quality features. With the option for advanced filtration systems, they can effectively remove airborne contaminants, contributing to a healthier indoor environment.

In summary, Carrier's 38HDR018-060 and 38HDF018-036 rooftop units are a powerful combination of efficiency, durability, and advanced technology. Their ability to provide customized heating and cooling solutions makes them an excellent investment for any commercial or industrial application, ensuring comfort and performance for years to come.