65
The TXV is set to maintain between 10 and 15 degrees of
superheat at the compressors. The valves are factory set and cannot
be adjusted. Do not use A TXV designed for use with R--22.
R4
RE
RI
RANT
RF
NM
NH
HS
20
40
60
80
10
12
14
16
150
200
25
00
350
400
450
500
550
600
ss
isc
ss
sig
dd
ha
bov
the
ur
ve
Ch
ar
if
lo
Cu
ve
Outdoor
Coil
eavin
Te mp
eratu
re,
[Deg
rees
F]
C07040
Fig. 35 -- Charging Chart ⎯ 48/50PD05
R4
RE
RI
RANT
RF
NM
NH
HS
20
40
60
80
10
12
14
16
150
200
25
00
350
400
450
500
550
600
ss
isc
ss
sig
dd
ha
bov
the
ur
ve
Ch
ar
if
lo
Cu
ve
Outdoor
Coil
eavin
Te mp
eratu
re,
[Deg
rees
F]
C07041
Fig. 36 -- Charging Chart ⎯ 48/50PD06
PuronR Refrigerant
Puron refrigerant operates at 50 to 70 percent higher pressures than
R-22. Be sure that servicing equipment and replacement
components are designed to operate with Puron refrigerant. Do not
mix with components that have been used with other refrigerants.
Puron refrigerant, as with other HFCs, is only compatible with
POE oils.
Recovery cylinder service pressure rating must be 400 psig. Puron
systems should be charged with liquid refrigerant. Use a
commercial-type metering device in the manifold hose. Manifold
sets should be 750 psig high-side and 200 psig low-side with 520
psig low-side retard. Use hoses with 750 psig service pressure
rating. Leak detectors should be designed to detect HFC
refrigerant.
Table 2 6 — Altitude Compensation*
48PG03--07
ELEVATION
(ft)
NATURAL GAS
ORIFICE†
PROPANE
ORIFICE†
0-1,999
45 52
2,000
47 52
3,000
47 53
4,000
47 53
5,000
48 53
6,000
48 53
7,000
48 53
8,000
49 54
9,000
49 54
10,000
50 54
11,000
51 54
12,000
51 55
13,000
52 55
14,000
52 56
*As the height above sealevel increases, there is less oxygen per cubic foot of air.
Therefore, heat input rate should be reduced at higher altitudes. Includes a 4%input
reduction per each 1000 ft.
† Orifices available through your Carrier dealer.
Gas Valve Adjustment
The gas valve opens and closes in response to the thermostat or
limit control.
When power is supplied to valve terminals W2 (High Fire) and C1,
the main valve opens to its preset position.
The regular factory setting is stamped on the valve body.
To adjust regulator:
1. Set unit at setting for no call for heat.
2. Turn main gas valve to OFF position.
3. Remove
1
/
8
-in. pipe plug from manifold pressure tap
connection. Install a suitable pressure-measuring device.
4. Set main gas valve to ON position.
5. Set thermostat at setting to call for heat.
6. Remove screw cap covering regulator adjustment screw.
(See Fig. 37.)
7. Turn adjustment screw clockwise to increase pressure or
counterclockwise to decrease pressure. The setting is 3.50
in.wgonsizes03-14and3.00onsize16--28.
8. Once desired pressure is established, set unit setting for no
call for heat, turn off main gas valve, remove
pressure-measuring device, and replace
1
/
8
-in. pipe plug and
screw cap.
C08663
Fig. 37 -- 48PD Gas Valve
48/50PD
