Rheem Raypak Hi Delta P902C Installation & Operating Instructions Manual page 26

3/4"
Model
No.
N
302C 15
402C
502C
652C
752C
902C
Natural gas – 1,000 BTU per ft
Propane gas – 2,500 BTU per ft
Reversing Gas Supply Connection (502C-
902C)
Reversing the standard fuel connection from the left-
hand to the right-hand side is a simple field operation.
1. Disconnect all electrical power from the heater (if
applicable).
2. Disconnect the main gas pipe from the heater (if
applicable).
3. Remove the left and right front panels from the
heater.
4. Locate the main gas line that traverses across the
heater above the manifold risers.
5. Remove the pipe cap from the right-hand end of
the main gas line.
6. Reinstall the pipe cap on the left-hand end of the
main gas line.
7. Remove the rubber grommet from the left-hand-
side panel and reinstall into the standard main gas
opening, located on the right-hand side of the
heater.
8. Remove plastic cap from the right-hand side panel
and reinstall into the standard main gas opening
located on the left-hand side of the heater.
9. Install a coupling, nipple, union and sediment trap
onto the right-hand end of the main gas line and
then install the gas line, making sure that a manual
shut-off valve has been installed within 10 ft of the
heater.
10. Replace the left and right front panels on the
heater.
1"
P N P
25 35 85
15 25 60
, .60 specific gravity at 0.5 in. WC pressure drop
3
, 1.53 specific gravity at 0.6 in. WC pressure drop
3
Table J: Maximum Equivalent Pipe Length
1-1/4" 1-1/2"
N P N
150 380 360
100 260 250
65 150 130
45 100 95
35 80 75
20 45 45
Gas Supply Pressure
A minimum of 5.6 in. WC upstream gas pressure
under full load and a maximum gas supply pressure
set point of 10.5 in. WC under load and no-load condi-
tions are required for natural gas. A minimum of 11.0
in. WC upstream gas pressure under full load and a
maximum gas supply pressure set point of 13.0 in. WC
are required for propane gas. The gas pressure regu-
lator(s) supplied on the heater is for low-pressure
service. If upstream pressure exceeds 14.0 in. WC
(1/2 psi) at any time, an intermediate gas pressure
regulator, of the lockup type, must be installed.
When connecting additional gas utilization equipment
to the gas piping system, the existing piping must be
checked to determine if it has adequate capacity for
the combined load.
The gas valve pressure regulator(s) on the heater are
nominally preset at 3.5 in. WC for natural gas, and
10.5 in. WC for propane gas. The pressure at the gas
valve outlet tap, measured with a manometer, while in
operation should be 3.5 ± 0.1 in. WC for natural gas
and 10.5 in. ± 0.1 in. WC for propane gas. If an adjust-
ment is needed, remove the adjustment screw cover
and turn the adjustment screw clockwise to increase
pressure or counter-clockwise to lower pressure.
NOTE: The maximum allowable pressure drop from
static to dynamic at full fire is 30%.
26
2"
P N P
350 500
250 340
180 260 600
110 150 360
2-1/2"
N P
400