Carrier MMY-MAP0724FT9UL Service Manual page 218

[When replacing normal as well as faulty compressor] - applicable to MMY-MAP072
<Dismantling normal compressor>
• Dismantle the normal compressor in the same way as the faulty compressor.
Note:
• Be sure to insulate the removed compressor leads using insulation tape, etc.
WARNING
When detaching a pipe by heating with a burner a welded joint, take care as any oil left in the piping may burn
in a momentary flash of fire when the weld filler metal melts.
<Measuring amount of oil in normal compressor>
• As was the case with the faulty compressor, measure the amount of oil contained by placing the compressor
on a scale.
Amount of oil in normal compressor: B [gal (cc)] = (Weight of compressor as it was dismantled (lb (kg)) - 50
(22.7)) × 0.1249 (1042) (Specific volume of oil: 0.1249 (1042) [gal/lb(cc/kg)])
Note:
• When a compressor is empty, it weighs 50lb (22.7kg).
<Adjusting amount of oil in new compressors>
• Perform the adjustment on the basis of how much oil the faulty compressor contained, A [gal (cc)], and how
much oil the normal compressor contained, B [gal (cc)], by following the steps below.
1
Combined amount of oil in faulty and normal compressors A+B [gal (cc)]: 0 ≤ ≤ ≤ ≤ ≤ A+B < 0.528
(2000)
(1) Adjust the amount of oil in the two new compressors to 0.264gal (1000cc) each (total 0.528gal (2000cc)).
• Lay the compressors down and draw 0.238gal (900cc) of oil from each of them via their oil equalization
pipes.
Notes:
• Do not draw more than 0.238gal (900cc) of oil from a compressor as it may cause damage.
• If the faulty compressor contained 0.132gal (500cc) or less, there may have been a problem with the oil
equalization circuit, etc. Perform checks in accordance with "12-3. Check Procedure to Search Cause of
Compressor Oil Shortage".
2
Combined amount of oil in faulty and normal compressors A+B [gal (cc)]: 0.528 (2000) ≤ ≤ ≤ ≤ ≤
A+B < 1.004 (3800)
(1) Adjust the amount of oil in the two new compressors to (A+B)/2 gal (cc) each.
• Lay the compressors down and draw [1.004 (3800)-(A+B)]/2 [gal (cc)] of oil from each of them via their oil
equalization pipes.
3
Combined amount of oil in faulty and normal compressors A+B [gal (cc)]: 1.004 (3800) ≤ ≤ ≤ ≤ ≤
A+B
(1) Adjust the amount of oil in the two new compressors to (A+B)/2 gal (cc) each.
(Insert a hose into the discharge pipe or oil equalization pipe of each compressor and inject (A+B)/2-0.502
(1900) [gal (cc)] of oil using a funnel, etc.)
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