Riello C9541400, Installation, Use And Maintenance Instructions

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Installation
4.10 Gas train
It must be type-approved according to UL Standards and is sup-
plied separately from the burner.
Key to layout
1 Gas input pipe
2 Manual valve
3 Pressure regulator
4 Low gas pressure switch
5 1
st
safety shut off valve
6 2
nd
safety shut off valve
7 Standard issue burner gasket with flange
8 Gas adjustment butterfly valve
9 Burner
4.11 Gas pressure
The Tab. D is used to calculate manifold pressure taking into ac-
count combustion chamber pressure.
Tab. D
Gas manifold pressure measured at test point 1)(Fig. 19), with:
•
combustion chamber at 0” WC;
• burner operating at maximum output;
• column 1: gas ring R2-R3)(Fig. 13) adjusted as indicated in di-
agram (Fig. 14);
• column 2: pressure loss at gas butterfly valve 8)(Fig. 18) with
maximum opening: 90°.
Calculate the approximate maximum output of the burner as fol-
lows:

subtract the combustion chamber pressure from the gas pres-
sure measured at test point 1)(Fig. 19);

find the nearest pressure value to your result in column 2 for
the burner in question;

read off the corresponding output on the left.
Example with natural gas G20
– Maximum output operation
– Gas ring 2-5)(Fig. 13) adjusted as indicated in diagram
(Fig. 14)
– Gas pressure at test point 1)(Fig. 19) = 3.69“ WC
– Pressure in combustion chamber = 0.79“ WC
3.69 - 0.79 = 2.90“ WC
A maximum output of 1136 MBtu/hr shown in Tab. D corresponds
to 2.90” WC pressure, column 1.
This value serves as a rough guide, the effective delivery must be
measured at the gas meter.
WARNING
See the accompanying instructions for the ad-
justment of the gas train.
Fig. 18
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GAS PILOT LINE
MAIN GAS LINE
MBtu/hr kW

p (“WC)
1 2
720 211 1.38 0.12
949 278 2.16 0.15
1136 333 2.90 0.19
1327 389 3.66 0.23
1515 444 4.21 0.27
1706 500 4.72 0.31
1894 555 5.12 0.35
2085 611 5.31 0.39
Fig. 19
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