Startup
36
RRU-SVX01F-EN
2. Check Inlet Gas Pressure
Check to insure the inlet gas pressure is within the
pressure requirement listed on the nameplate. DO
NOT expose gas controls to pressures above 1/2 psi
(14 in. wc). The gas supply line should be installed with
an external manual shutoff and pressure tap.
Note:
If burner pressure drop is not within the range
shown in
.
3. Check Inlet Gas Pressure and Confirm Gas Flow
to Unit
Confirm gas flow and gas supply pressure to heater.
The Manual Shut-Off valve (MSO1) can be used to
bleed the supply line as needed.
After confirming gas flow to unit, verify and record gas
pressure at PG1.
4. Heating Starting Sequence for Gas Input Rating
400 MBh
Important:
Open shut off vales at MSO1, MSO2, and
Main Gas Valve (MGV) before proceeding.
.
Figure 17.
Air proving switch location
Table 6.
Acceptable measured pressures
OAT (°F)
Burner Pressure Drop (in. wc)
0
0.720
5
0.712
10
0.705
15
0.697
20
0.690
25
0.683
30
0.676
35
0.669
40
0.663
45
0.656
50
0.650
55
0.643
60
0.637
65
0.631
70
0.625
(a)
(a) 0.625-in. design pressure drop at standard air conditions.
Allowable pressure range at 70°F is 0.55 to 0.75 in. wc.
75
0.619
80
0.613
85
0.608
90
0.602
95
0.597
100
0.592
WARNING
Hazard of Explosion!
Failed gas components could explode or leak
flammable gas which could cause a fire resulting in
death or serious injury or property damage. Do NOT
expose gas controls to pressures above 1/2 psi
(3.5 kPa).
•
Heater main gas shut-off valve and controls MUST be
isolated when testing gas supply piping at pressures
in excess of 1/2 psi (3.5 kPa).
•
Heater main gas shut-off valve MUST be closed when
testing gas supply piping at pressures equal to or less
than 1/2 psi (3.5 kPa).
Refer to
“General Safety Information,” p. 5
.
