Cleaning, Evaporator Coil, Condenser coil

48HE,HJ

C06136

Fig. 54 ---Humidi-MiZer Subcooling

Mode Operation

C06137

Fig. 55 ---Humidi-MizertHot Gas

Reheat Mode Operation

Hot Gas Reheat Mode

When the humidity levels in the space require humidity control, a hot gas solenoid valve (specific to hot gas reheat mode only) will open to bypass a portion of hot gas refrigerant around the condenser coil. (See Fig. 55.)

This hot gas will mix with liquid refrigerant leaving the condenser coil and flow to the subcooling/reheat dehumidification coil. Now the conditioned air coming off the evaporator will be cooled and dehumidified, but will be warmed to neutral conditions (72_F to 75_F) by the subcooling/reheat dehumidification coil.

The net effect of the rooftop when in hot gas reheat mode is to provide nearly all latent capacity removal from the space when sensible loads diminish (when outdoor temperature conditions are moderate). When in hot gas reheat mode, the unit will operate to provide mostly latent capacity and extremely low sensible heat ratio capability.

Similar to the subcooling mode of operation, hot gas reheat mode operates only when the outside air temperature is warmer than 40_F. Below this temperature, a factory installed outside air temperature switch will lockout this mode of operation.

See Table 39 for the Humidi-Mizer adaptive dehumidification system sequence of operation.

SERVICE

!WARNING

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could cause personal injury or death.

When sevicing unit, shut off all electrical power to unit and install lockout tag to avoid shock hazard or injury from rotating parts.

Step 1 —Cleaning

Inspect unit interior at the beginning of heating and cooling season and as operating conditions require.

EVAPORATOR COIL

1.Turn unit power off, tag disconnect. Remove evaporator coil access panel.

2.If economizer or two-position damper is installed, remove economizer by disconnecting Molex plug and removing mounting screws.

3.Slide filters out of unit.

4.Clean coil using a commercial coil cleaner or dishwasher detergent in a pressurized spray canister. Wash both sides of coil and flush with clean water. For best results, back-flush toward return-air section to remove foreign material. Flush condensate pan after completion.

5.Reinstall economizer and filters.

6.Reconnect wiring.

7.Replace access panels.

Condenser coil

Inspect coil monthly. Clean condenser coil annually, and as required by location and outdoor air conditions.

One-Row Coils

Wash coil with commercial coil cleaner. It is not necessary to remove top panel.

2-Row Coils

Clean coil as follows:

1.Turn off unit power, tag disconnect.

2.Remove top panel screws on condenser end of unit.

3.Remove condenser coil corner post. (See Fig. 56.) To hold top panel open, place coil corner post between top panel and center post. (See Fig. 57.)

C06044

Fig. 56 ---Cleaning Condenser Coil

48HJ004---007, 48HE003---006 specifications

Carrier has long been a trusted name in the HVAC industry, and its models 48HJ004---007 and 48HE003---006 continue that legacy, offering efficient, reliable climate control solutions. These models are designed for different applications, ensuring optimal performance in a variety of environments.

The 48HJ series features advanced rooftop units that are ideal for commercial settings. They come equipped with high-efficiency scroll compressors that provide superior cooling and heating capabilities. This series is noted for its compact design, allowing for easy installation on rooftops or other constrained spaces. The units offer variable capacity operation, which enables them to efficiently meet varying heating and cooling demands without unnecessary energy consumption.

One of the standout features of the 48HJ series is its use of advanced microprocessor controls. This technology allows for precise temperature management and system diagnostics, enhancing the ease of operation while ensuring maximum comfort. Additionally, the series supports advanced connectivity options, enabling integration with building management systems. This allows for remote monitoring and control, making it easier for facility managers to keep track of performance and energy usage.

On the other hand, the 48HE series specializes in high-efficiency heating and cooling performance. These units are designed for larger commercial spaces and come with robust features for enhanced durability and efficiency. Like the 48HJ series, the 48HE models utilize scroll compressors and are equipped with a high-efficiency fan setup for improved airflow and reduced noise levels.

The 48HE also includes an innovative heat pump option, which allows the system to reverse the cooling process to provide heating, making it versatile across different seasonal demands. Both series are designed with eco-friendly refrigerants that comply with the latest environmental regulations, ensuring a minimized ecological footprint.

In terms of energy efficiency, both the 48HJ and 48HE series hold impressive SEER and EER ratings, contributing to reduced operational costs over time. The units are also built with durable, corrosion-resistant materials, ensuring longevity and low maintenance needs.

In conclusion, Carrier 48HJ004---007 and 48HE003---006 models are designed with cutting-edge technology, energy efficiency, and flexibility in mind. Their robust features make them ideal choices for commercial applications, providing reliable comfort and operational excellence. Whether for cooling or heating, these systems stand out in performance and sustainability, earning Carrier's reputation as a leader in the HVAC market.

Carrier 48HE003---006, 48HJ004---007 Cleaning, Evaporator Coil, Condenser coil, One-Row Coils

Models: 48HJ004---007 48HE003---006