Beckett RWF40 CG15 Manuel D’Utilisation

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Check Operation and Safety Controls
Figure 14C - Manifold to Furnace Pressure Drop vs Rate CG50*
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1000
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5000
6000
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0.5
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Pressure Drop, In. WC
Rate, MBH
CG50.5S
CG50.4S
CG50.3S
CG50.2S
CG50.1S
* Charts represent both natural and propane gas. 
Testing by Qualifi ed 
Technician Required.
Failure to properly test and verify the correct 
function of operation and safety controls could lead 
to equipment malfunction and result in asphyxiation, 
explosion or fi re.
The testing of operation and safety controls requires 
technical training and experience with commercial 
gas burning systems.
Carefully follow the manufacturer’s instructions 
supplied with the controls.
Verify the correct function of all operation and safety 
controls used in the installation.
If instructions are not available, use the following 
recommended procedures and record all results in a 
start-up log.
Refer to Figure 7 for typical test points and 
component locations.
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Section: Start the Burner
Operating control – Run the burner until the 
operating control shuts it off. If necessary, make 
adjustments to ensure the control cycles the burner 
in the desired temperature or pressure range. 
 
 
 
 
 
 
 
 
Operating controls should be 
set to minimize the number of 
fi ring cycles that the burner runs.  High cycling rates 
increase the possibility of light-off lock outs.
Low water cutoff (LWCO) – With the burner fi ring, 
open the blow down valve on the low water cutoff, 
if applicable. As the water level drops, the LWCO 
switch contacts open and shut the burner off. When 
the water level rises, the LWCO contacts close 
and restart the burner. Monitor the LWCO switch 
operation in relation to the water level in the sight-
glass for synchronization.
Airfl ow proving switch – With the burner fi ring at 
its lowest rate, loosen the tubing connection to the 
airfl ow proving switch. A loss in air pressure at the 
tubing should immediately cause the diaphragm 
in the switch to open and recycle or lockout the 
safeguard control.
Low gas pressure switch – With the burner fi ring 
and a manometer attached to a test port near 
the low pressure switch, gradually close the main 
leak test cock to shut off the gas supply. Note the 
pressure at which the low gas pressure switch 
opens and shuts the burner off. Manually reset the 
switch. The low gas pressure switch should be set 
at half of the normal supply pressure in the line.
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High limit – To check the High Limit, raise the 
temperature or pressure of the operating control to 
a higher level and lower the limit to a setting less 
than the operating control. Run the burner until the 
high limit opens and shuts the burner off. Adjust the 
controls back to the desired settings.
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