Evacuation

Proper evacuation of the system will remove non-condensibles and assure a tight, dry system before charging. The 2 methods used to evacuate a system are the deep vacuum method and the triple evacuation method.

Deep Vacuum Method

The deep vacuum method requires a vacuum pump capable of pulling a vacuum of 500 microns and a vacuum gauge capable of accurately measuring this vacuum depth. The deep vacuum method is the most positive way of assuring a system is free of air and moisture. (See Fig. 30.)

 

5000

 

 

 

 

 

 

 

 

4500

 

 

 

 

 

 

 

 

4000

 

 

 

 

 

LEAK IN

 

3500

 

 

 

 

 

MICRONS

 

 

 

 

 

SYSTEM

3000

 

 

 

 

 

 

 

 

 

 

 

 

2500

 

 

 

 

 

 

 

2000

 

 

 

 

 

 

 

 

 

 

 

 

 

VACUUM TIGHT

 

1500

 

 

 

 

 

 

 

 

 

 

 

TOO WET

 

1000

 

 

 

 

 

 

 

 

 

 

 

TIGHT

 

500

 

 

 

 

 

 

 

 

 

 

 

DRY SYSTEM

 

 

 

 

 

 

 

 

0

1

2

3

4

5

6

7

 

 

 

 

MINUTES

 

 

 

 

 

 

 

 

 

 

 

A95424

Fig. 30 – Deep Vacuum Graph

Triple Evacuation Method

The triple evacuation method should be used when vacuum pump is only capable of pumping down to 28 in. of mercury vacuum and system does not contain any liquid water. Refer to Fig. 31 and proceed as follows:

1.Pump system down to 28 in. of mercury and allow pump to continue operating for an additional 15 minutes.

2.Close service valves and shut off vacuum pump.

3.Connect a nitrogen cylinder and regulator to system and open until system pressure is 2 psig.

4.Close service valve and allow system to stand for 1 hr. During this time, dry nitrogen will be able to diffuse throughout the system absorbing moisture.

5.Repeat this procedure as indicated in Fig. 31. System will then be free of any contaminants and water vapor.

EVACUATE

BREAK VACUUM WITH DRY NITROGEN

WAIT

EVACUATE

BREAK VACUUM WITH DRY NITROGEN

WAIT

EVACUATE

CHECK FOR TIGHT, DRY SYSTEM (IF IT HOLDS DEEP VACUUM)

CHARGE SYSTEM

A95425

Fig. 31 – Triple Evacuation Method

CHECK CHARGE

(See Charging Tables 11 & 13)

Factory charge amount and desired subcooling are shown on unit rating plate. Charging method is shown on information plate inside unit. To properly check or adjust charge, conditions must be favorable for subcooling charging. Favorable conditions exist when the outdoor temperature is between 70_F and 100_F (21.11_C and 37.78_C), and the indoor temperature is between 70_F and 80_F (21.11_C and 26.67_C). Follow the procedure below:

Unit is factory charged for 15ft (4.57 m) of lineset. Adjust charge by adding or removing 0.6 oz/ft of 3/8 liquid line above or below 15ft (4.57 m) respectively.

For standard refrigerant line lengths (80 ft/24.38 m or less), allow system to operate in cooling mode at least 15 minutes. If conditions are favorable, check system charge by subcooling method. If any adjustment is necessary, adjust charge slowly and allow system to operate for 15 minutes to stabilize before declaring a properly charged system.

If the indoor temperature is above 80_F (26.67_C), and the outdoor temperature is in the favorable range, adjust system charge by weight based on line length and allow the indoor temperature to drop to 80_F (26.67_C) before attempting to check system charge by subcooling method as described above.

If the indoor temperature is below 70_F (21.11_C), or the outdoor temperature is not in the favorable range, adjust charge for line set length above or below 15ft (4.57 m) only. Charge level should then be appropriate for the system to achieve rated capacity. The charge level could then be checked at another time when the both indoor and outdoor temperatures are in a more favorable range.

NOTE: If line length is beyond 80 ft (24.38 m) or greater than 20 ft (6.10 m) vertical separation, See Long Line Guideline for special charging requirements.

33

Page 33
Image 33
Bryant R-22 service manual Check Charge, Evacuation, Deep Vacuum Method

R-22 specifications

The Bryant R-22 stands out in the landscape of residential heating and cooling systems with its combination of efficiency, durability, and modern technology. Designed primarily for homeowners seeking comfortable climate control solutions, the R-22 model delivers consistent performance throughout varying seasonal extremes.

One of the main features of the Bryant R-22 is its high energy efficiency. Rated with a SEER (Seasonal Energy Efficiency Ratio) that meets or exceeds industry standards, this air conditioning unit is designed to reduce energy consumption while providing optimal cooling. This not only helps in lowering monthly utility bills but also promotes environmentally responsible usage.

Another notable characteristic is the unit's durability. Constructed with a robust cabinet and high-quality components, the R-22 is built to withstand the rigors of daily use, with protective features that enhance its longevity. The cabinet comes with a powder-coated finish that resists corrosion and harsh weather conditions, ensuring that the unit stays functional and aesthetically pleasing for years.

The Bryant R-22 also incorporates advanced technology to improve user experience. One such innovation is the SmartSet technology, which allows homeowners to program their unit to optimize comfort levels according to their specific needs. This programmable capability enhances energy savings and ensures that the home remains at the desired temperature when residents are present.

Moreover, the unit features a Quiet Operating System that significantly reduces noise levels, making it suitable for residential areas where noise might be a concern. The design minimizes vibrations and optimizes airflow, creating a comfortable environment without disruptive sounds.

For added convenience, the Bryant R-22 is compatible with various thermostat options, including Wi-Fi-enabled models. This allows users to control their home's climate from anywhere using a smartphone app, facilitating effortless adjustments and monitoring of energy usage.

Finally, the Bryant R-22 is backed by a solid warranty, providing peace of mind for homeowners. This commitment to quality and customer satisfaction is a testament to Bryant’s dedication to producing reliable and efficient HVAC solutions. Overall, the Bryant R-22 is an exemplary choice for those looking to enhance their home comfort with the latest in HVAC technology.