Carrier 09BY006-024 Ð Install Rain Drain See Fig, Ð Complete Refrigerant Piping, Ð Rain Drains

Step 3 Ð Install Accessory Low-Ambient Kit or Inlet Filter Kit (If Required) Ð If the unit will be op- erated with inlet air to the condenser below 50 F, a low- ambient damper may be required. The low-ambient kit con- trols head pressure by discharge dampers on the condenser fan. The dampers are actuated by a refrigerant-operated pis- ton connected to the discharge line of the condenser. If low- ambient accessory will be used, install it at this time (before ®nal refrigerant and ductwork connections are made).

An accessory ®lter rack may also be installed on the con- denser air inlet to help keep the coil clean. This ®lter rack should be installed before the ductwork is attached to the unit, and before unit is mounted against a wall louver (if required in your speci®c application).

Refer to installation instructions provided with the acces- sories for installation details.

Step 4 Ð Install Rain Drain (See Fig. 7)

IMPORTANT: A rain drain connection MUST BE USED if any possibility exists of rain water entering the unit.

The 09BY unit provides a choice of 2 drain locations. Rain drain connection can be made on either side of the unit. Block whichever drain is not being used, but DO NOT BLOCK BOTH drain locations.

NOTE: Dimensions in [ ] are in millimeters.

Fig. 7 Ð Rain Drains

A drain kit is provided (shipped in the fan section). This kit consists of PVC drain ®ttings to adapt to ®eld-supplied threaded pipe. Make connections through the unit side panel. Some applications may require connection to either galva- nized steel or copper drain pipe; consult local code require- ments for details.

If unit is located inside the building, the drain connection near the refrigerant piping can be used for external drainage. Run drain connection to a trapped drain, and plug unused connection.

IMPORTANT: NEVER use pipe smaller than 3¤4 in. in the drain run.

For vertical discharge units, provide a rain drain on the back of the unit.

Pitch drain pipe downward at a slope of at least 1¤4-in. per ft for proper drainage. Provide tees plugged on one side for cleanouts. Leave clearance for servicing, and observe all lo- cal sanitary codes.

Refer to Carrier System Design Manual for additional pip- ing details.

Step 5 Ð Complete Refrigerant Piping

GENERAL Ð All ®eld leak and pressure testing should be done in accordance with local code requirements. If a local code does not exist, use ASHRAE (American Society of Heat- ing, Refrigeration and Air Conditioning Engineers) Stand- ard 15, Safety Code for Mechanical Refrigeration.

For leak testing procedures, refer to the Carrier ``Refrig- erant Service Techniques'' book, Form SFT-01.

For any parts that need to be removed, use a mini tubing cutter. Perform phos-copper brazing on all ®eld-made con- nections while protecting adjacent joints from heat.

REFRIGERANT LINE SIZING Ð Sizing depends on length of lines between various sections of the refrigerant system. Consider the amount of liquid lift and drop in the system as well as proper compressor oil return. Consult Carrier System Design Manual, Part 3, or Carrier E20-II Refrig- erant Piping Computer Program for proper piping sizes and design.

PRESSURE RELIEF Ð The ASHRAE Standard 15, Safety Code for Mechanical Refrigeration states: ``Every refriger- ating system shall be protected by a pressure relief device or some other means designed to safely relieve pressure due to ®re or other abnormal conditions.'' Since 09BY condensers do not have pressure relief devices, one must be ®eld sup- plied and installed either before the liquid line service valve or inside the 09BY unit. Each circuit must have its own pres- sure relief.

If desired, the pressure relief requirement can also be sat- is®ed by installing a fusible plug in the liquid line. To do so, install a tee in the liquid line with a 1¤4-in. NPT ®tting on the tee side, and install a fusible plug (part no. EK02KK105 or similar). The temperature rating of the fusible plug should be between 205 F and 220 F (96 C and 104 C). If a service valve is used on the liquid line, be sure that both the piping system and the condenser are protected for relief if all serv- ice valves are closed. Note that if the condenser is located indoors, requirements for venting the fusible plug to the out- doors may apply. Consult local code requirements.

REFRIGERANT RECEIVER Ð A refrigerant receiver is not furnished with 09BY condensers and is not recommended for normal applications.

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