Carrier 30RAP010-060 specifications Oil Charge, Check Refrigerant Feed Components

2.Disconnect the liquid-in and liquid-out connections at the heat exchanger.

3.Recover the refrigerant from the system, and unsolder the refrigerant-in and refrigerant-out connections.

4.Remove the old heat exchanger. The replacement heat ex- changer is supplied fully insulated. It also includes a cool- er heater. Use of the heater is not required unless the orig- inal cooler contained a factory installed heater.

5.Install the replacement heat exchanger in the unit and at- tach the mounting bracket hardware to the fan uprights (sizes 010-030) or to the bottom bracket (sizes 035-060) using the hardware removed in Step 4. Reconnect the cooler heater if required. For sizes 010-025, torque the bolts to 7-10 ft-lb. For sizes 030-060, torque the bolts to 30-50 ft-lb.

6.Carefully braze the refrigerant lines to the connections on the heat exchanger. Lines should be soldered using silver as the soldering material with a minimum of 45% silver. Keep the temperature below 1472 F (800 C) under nor- mal soldering conditions (no vacuum) to prevent the cop- per solder of the brazed plate heat exchanger from chang- ing its structure. Failure to do so can result in internal or external leakage at the connections which cannot be re- paired. Braze the liquid lines with a heat sink around the expansion valve to protect it from excess heat.

7.Reconnect the water/brine lines.

8.Dehydrate and recharge the unit. Check for leaks.

BRAZED-PLATE COOLER HEAT EXCHANGER CLEANING — Brazed-plate heat exchangers must be cleaned chemically. A professional cleaning service skilled in chemical cleaning should be used. Use a weak acid (5% phos- phoric acid, or if the heat exchanger is cleaned frequently, 5% oxalic acid). Pump the cleaning solution through the exchanger, preferably in a backflush mode. After cleaning, rinse with large amounts of fresh water to dispose of all the acid. Cleaning materials must be disposed of properly.

The factory-installed strainer screen in front of the water/ brine inlets of the heat exchangers should be cleaned periodi- cally, depending on condition of the chiller water/brine.

Oil Charge

CAUTION

The compressor in a Puron® refigerant (R-410A) system uses a polyol ester (POE) oil. This is extremely hygro- scopic, meaning it absorbs water readily. POE oils can absorb 15 times as much water as other oils designed for HCFC and CFC refrigerants. Take all necessary precau- tions to avoid exposure of the oil to the atmosphere. Failure to do so could result in possible equipment damage.

Puron refrigerant systems use a polyol ester (POE) oil. Use only Carrier approved compressor oil. Oil should be visible in compressor oil sight glass. An acceptable oil level is from 1/8 to 3/8 of sight glass. All compressors must be off when checking oil level. Recommended oil level adjustment method is as follows:

ADD OIL — Recover charge from the unit. Add oil to suction line Schrader valve on tandem compressors sets and the com- pressor Schrader on the trio's and single compressor circuits. (See Fig. 26 and 27.) When oil can be seen at the bottom of the sight glass, add oil in 5 oz increments which is approximately 1/8 in oil level. Run all compressors for 20 minutes then shut off to check oil level. Repeat procedure until acceptable oil level is present.

NOTE: Use only Carrier approved compressor oil. Approved sources are:

Totaline . . . . . . . . . . . . . . . . . . . . . . 3MAF POE, P903-1601

Mobil . . . . . . . . . . . . . . . . . . . . . . . . . . .EAL Arctic 32-3MA Uniqema . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . RL32-3MAF Do not reuse oil that has been drained out, or oil that has

been exposed to atmosphere.

Microchannel Heat Exchanger (MCHX) Con- denser Coil Maintenance and Cleaning Recommendations

CAUTION

Do not apply any chemical cleaners to MCHX condenser coils. These cleaners can accelerate corrosion and damage the coil.

Routine cleaning of coil surfaces is essential to maintain proper operation of the unit. Elimination of contamination and removal of harmful residues will greatly increase the life of the coil and extend the life of the unit. The following steps should be taken to clean MCHX condenser coils:

1.Remove any foreign objects or debris attached to the coreface or trapped within the mounting frame and brackets.

2.Put on personal protective equipment including safety- glasses and/or face shield, waterproof clothing and gloves. It is recommended to use full coverage clothing.

3.Start high pressure water sprayer and purge any soap or industrial cleaners from sprayer before cleaning condens- er coils. Only clean, potable water is authorized for clean- ing condenser coils.

4.Clean condenser face by spraying the core steady and uniformly from top to bottom while directing the spray straight toward the core. Do not exceed 900 psig or 30 de- gree angle. The nozzle must be at least 12 in. from the core face. Reduce pressure and use caution to prevent damage to air centers.

CAUTION

Excessive water pressure will fracture the braze between air centers and refrigerant tubes.

Check Refrigerant Feed Components

FILTER DRIER — The function of the filter drier is to main- tain a clean, dry system. The moisture indicator (described below) indicates any need to change the filter drier. The filter drier is a sealed-type drier. When the drier needs to be changed, the entire filter drier must be replaced.

NOTE: Dual circuit (035-060 sizes) units have 1 filter drier per circuit.

MOISTURE-LIQUID INDICATOR — The indicator is located immediately ahead of the TXV to provide an indication of the refrigerant moisture content. It also provides a sight glass for refrigerant liquid. Clear flow of liquid refrigerant (at full unit loading) indicates sufficient charge in the system. Bubbles in the sight glass (at full unit loading) indicate an undercharged system or the presence of noncondensables. Moisture in the system, measured in parts per million (ppm), changes the color of the indicator as follows:

Green (safe) —Moisture is below 75 ppm Yellow-Green (caution) — 75 to 150 ppm Yellow (wet) — above 150 ppm

The unit must be in operation at least 12 hours before the moisture indicator gives an accurate reading, and must be in contact with liquid refrigerant. At the first sign of moisture in the system, change the corresponding filter drier.

NOTE: Dual circuit (035-060 sizes) units have one indicator per circuit.

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