Rtpf (Round Tube Plate Fin) Condenser Coil Maintenance; Oil Charge; Brazed-Plate Cooler Heat Exchanger; Microchannel Heat Exchanger (Mchx) Condenser Coil Maintenance And Cleaning - Carrier AQUASNAP 30RAP010-150 Controls, Start-Up, Operation, Service, And Troubleshooting

Cooler
BRAZED-PLATE COOLER HEAT EXCHANGER RE-
PLACEMENT — Brazed-plate heat exchangers cannot be
repaired if they develop a leak. If a leak (refrigerant or water)
develops, the heat exchanger must be replaced. To replace a
brazed-plate heat exchanger:
1. Check that the replacement heat exchanger is the same as
the original heat exchanger. The unit insulation covers the
manufacturer's part number. Make sure the depths of the
replacement and original cooler heat exchangers are the
same.
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 035-150)
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 030-150, 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
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
uses a polyoester (POE) oil. This is extremely hygroscopic,
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 precautions 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
3 / of sight glass for unit size 010-090, and
8
glass for unit size 100-150. All compressors must be off when
HEAT EXCHANGER
® refrigerant (R-410A) system
1
3 / to 7 / of sight
4 8
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 three-compressor circuits and single-
compressor circuits. (See Fig. 34-36.) When oil can be seen at
the bottom of the sight glass, add oil in 5 oz increments which
is approximately
minutes then shut off to check oil level. Repeat procedure until
acceptable oil level is present.
NOTE: Use only Carrier-approved compressor oil.
• Oil Type . . . . . . . . . . . . . . . . Inhibited polyol ester-based
• ISO Viscosity Grade . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Approved sources are:
UNIT SIZES 010-090
MANUFACTURER
Totaline . . . . . . . . . . . . . . . . . . . . . . 3MAF POE, P903-1601
Mobil. . . . . . . . . . . . . . . . . . . . . . . . . . . EAL Arctic 32-3MA
Uniqema (ICI). . . . . . . . . . . . . . . . Emkarate RL32-3MAF
UNIT SIZES 100-150
MANUFACTURER
Uniqema (ICI). . . . . . . . . . . . . . . . . . . .Emkarate RL 32H
Do not reuse drained oil or any oil that has been exposed to
the atmosphere.
Microchannel Heat Exchanger (MCHX) Con-
denser Coil

Recommendations

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 coil
face 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 coil steady and uni-
formly from top to bottom while directing the spray
straight toward the coil. Do not exceed 900 psig or
30 degree angle. The nozzle must be at least 12 in. from
the coil face. Reduce pressure and use caution to prevent
damage to air centers.
RTPF (Round Tube Plate Fin) Condenser Coil
Maintenance and Cleaning Recommenda-
Routine cleaning of coil surfaces is essential to
tions —
maintain proper operation of the unit. Elimination of contami-
nation and removal of harmful residues will greatly increase
/ to
the life of the coil and extend the life of the unit. The following
8
maintenance and cleaning procedures are recommended as part
55
1 / in oil level. Run all compressors for 20
8
synthetic compressor lubricant.
Maintenance and
CAUTION
OIL
OIL
Cleaning