Carrier 26H - Manual (Page 26)

26H S E R V I C E
Carrier
4. CHARGING WITH REFRIGERANT
TABLE 1 - REFRIGERANT CHARGE (R12)
MODEL IDENTIFICATION CHARGE
26H5 No changes 3 lb. 8 oz.
26H3 9 " condenser and 9 " accum. 1 lb. 11 oz.
26H3 Serial No. 331784 Change to 18"cond.- 2 lb. 3 oz.
9 " accumulator
26H3 Serial No. 411152 change to 15"cond.- 2 lb. 3 oz.
9 " accumulator
26H3 Serial No. 510446 change to 15"cond.—
10 1/2" accumulator 2 lb. 9 oz.
If the unit is undercharged, back seat the suction
shutoff valve. Remove a gauge port plug from the
valve; connect a charging line from a drum of re­
frigerant 12. Tighten this line at the drum, but make
a loose connection at the suction shutoff valve.
Crack the valve on the drum so that refrigerant va­
por will force air from the charging line out the
loose connection. After purging the air from the
charging line, tighten the connection at the suc­
tion shut-off valve. Open the suction valve to a
point midway between the back-seated and front-
seated positions. With the suction shutoff valve in
this position, it is possible to read the system pres­
sure during the charging period. The refrigerant 12
drum should be in an upright position to admit va­
por only.
If the unit is overcharged, turn the unit off. Back
seat the discharge shutoff valve. Attach a charg­
ing line to one of the gauge ports in the valve and
attach a charging manifold to the other end of the
charging line. Turn the shutoff valve to the middle
position; start the unit. Bleed refrigerant from the
charging manifold in 5-second intervals until the
charge is correct. Turn the unit off. Back seat the
shutoff valve and remove the charging line. Replace
the gauge port plug and start the unit.
WEIGHING IN CHARGE
The most accurate method of charging a refrigerant
system is weighing in the charge. Proceed as fol­
lows:
1. Bleed any charge remaining in the system,
then start the compressor and pump out the
system through the discharge valve.
2. With the compressor still running, connect the
drum of refrigerant to the suction valve.
3. Back seat the discharge valve and immediately
turn off the compressor.
4. Weigh the drum of refrigerant (it is easier to
weigh a charge if the weight of the drum can
*, be checked during the charging process).
5. Open the suction valve and crack the valve
on the drum of refrigerant. Start the compressor.
6. Continue to charge until the scale shows the
proper amount of refrigerant has been fed into
the system.
7. Close the valve on the drum and then the suc­
tion shutoff valve.
8. Disconnect the charging line.
9. Leak test the system.
i
t
26H-57PD 26