H E AT C O N T R O L L E R , I N C . WAT E R - S O U R C E H E AT P U M P S

R e s i d e n t i a l S p l i t - 6 0 H z R 2 2 & R 4 1 0 A

R e v. : 5 J u n e , 2 0 0 8

Refrigeration Installation

Figure 10: Braze Instructions

Figure 11: Air Coil Connection

Table 5: Service Valve Positions

Position

Description

System

Service

 

 

 

Port

CCW - Full Out

Operation Position

Open

Closed

 

 

 

 

CCW - Full Out 1/2 turn CW

Service Position

Open

Open

 

CW - Full In

Shipping Position

Closed

Open

Figure 11 shows the installation of the lineset and TXV to a typical indoor coil. An indoor coil or air handler (fan coil) with a TXV is required. Coils with cap tubes may not be used. If coil includes removable fixed orifice, the orifice must be removed and a TXV must be installed as shown in Figure 11. Fasten the copper line set to the coil. Nitrogen should be circulated through the system at 2-3 psi [13.8-20.7 kPa] to prevent oxidation inside the refrigerant tubing. Use a low silver phos-copper braze alloy on all brazed connections.

Add-On Heat Pump Applications

The indoor coil should be located in the supply side of the furnace to avoid condensation damage to the furnace heat exchanger for add-on heat pump applications. A high temperature limit switch should be installed as shown in Figures 12b and 13b just upstream of the coil to de-energize the compressor any time the furnace is energized to avoid blowing hot air directly into the coil, elevating refrigerant pressures during operation. The heat pump will trip out on high pressure lockout without some method of disengaging the compressor during furnace operation. Alternatively, some thermostats with “dual fuel” mode will automatically de- energize the compressor when second stage (backup) heat is required.

The TXV should be brazed into place as shown in Figure 11, keeping the “IN” side toward the compressor section. The TXV has an internal check valve and must be installed in the proper direction for operation. Always keep the valve body cool with a brazing shield and wet rags to prevent damage to the TXV. Attach the bulb to the suction line using the supplied hose clamp. Be careful not to overtighten the clamp and deform the bulb.

NOTICE! The air coil should be thoroughly washed with a filming agent, (dishwasher detergent like Cascade) to help condensate drainage. Apply a 20 to 1 solution of detergent and water. Spray both sides of coil, repeat and rinse thoroughly with water.

Evacuation and Charging the Unit

LEAK TESTING - The refrigeration line set must be pressurized and checked for leaks before evacuating and charging the unit. To pressurize the line set, attach refrigerant gauges to the service ports and add an inert gas (nitrogen or dry carbon dioxide) until pressure reaches 60-90 psig [413-620 kPa]. Never use oxygen or acetylene to pressure test. Use a halogen leak tester or a good quality bubble solution to detect leaks on all connections made in the field. Check the service valve ports and stem for leaks. If a leak is found, repair it and repeat the above steps. For safety reasons do not pressurize system above 150 psig [1034 kPa]. System is now ready for evacuation and charging.

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H e a t C o n t r o l l e r, I n c . Wa t e r - S o u r c e H e a t i n g a n d C o o l i n g S y s t e m s

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Heat Controller HTS SERIES SPLIT SYSTEM, HSS manual Add-On Heat Pump Applications, Evacuation and Charging the Unit