Burnham 20_PV_I User Manual
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Figure 16: Main Burner Flame
J.
Check thermostat operation. Raise and lower
temperature setting to start and stop boiler operation.
K.
Check ignition control module shut-off. Disconnect
igniter/sensor cable from Terminal 9 (SPARK). Gas
valve should close and pilot and main burners should
extinguish.
L.
Check low water cutoff (if used). Drain boiler water
below LWCO set point. Burners should extinguish.
M.
Check limit.
1. Adjust thermostat to highest setting.
2. Observe temperature gauge. When temperature is
indicated, adjust limit to setting below observed
temperature. Main burners and pilot burner should
extinguish and blower stop.
3. Adjust limit to setting above observed temperature.
Ignition sequence should begin.
4. Adjust thermostat to lowest setting. Adjust limit to
desired setting.
N.
Adjust gas input rate to boiler (Natural Gas).
1. Adjust thermostat to highest setting.
2. Check manifold gas pressure. Manifold pressure is
listed on rating label. Adjust gas valve pressure
regulator as necessary (turn adjustment screw
counterclockwise to decrease manifold pressure, or
clockwise to increase manifold pressure). If
pressure can not be attained, check gas valve inlet
pressure. If less than minimum gas supply pressure
listed on rating label, contact gas supplier for
assistance.
3. Clock gas meter for at least 30 seconds. Use Table 6
to determine gas flow rate in Cubic Feet per Hour.
4. Determine Input Rate. Multiply gas flow rate by gas
heating value.
5. Compare measured input rate to input rate listed on
rating label.
Seconds
for One
Revolution
Size of Gas Meter Dial
One-Half
Cu. Ft.
One
Cu. Ft.
Two
Cu. Ft.
30
60
120
240
32
56
113
225
34
53
106
212
36
50
100
200
38
47
95
189
40
45
90
180
42
43
86
172
44
41
82
164
46
39
78
157
48
37
75
150
50
36
72
144
52
35
69
138
54
33
67
133
56
32
64
129
58
31
62
124
60
30
60
120
Table 6: Gas Flow Rate in Cubic Feet per Hour
a. Boiler must not be overfired. Reduce input rate
by decreasing manifold pressure. Do not reduce
more than 0.3 inch w.c. If boiler is still
overfired, contact your Burnham distributor or
Regional Office for replacement Gas Orifice.
b. Increase input rate if less than 98% of rating
label input. Increase manifold gas pressure no
more than 0.3 inch w.c. If measured input rate is
still less than 98% of rated input:
i.
Remove Main Burners per procedure in
Section VIII: Service.
ii. Remove gas orifices. Drill one (1) drill size
larger (drill size is stamped on orifice, or
see Key No. 4D).
iii. Reinstall gas orifices and main burners.
Measure input rate.
6. Recheck Main Burner Flame.
7. Adjust thermostat to normal setting.
8. Return other gas-fired appliances to previous
conditions of use.
O.
Adjust gas input rate to boiler (LP/Propane).
1. Adjust thermostat to highest setting.
2. Check manifold pressure. Adjust gas valve pressure
regulator to obtain 10 inches w.c. manifold