Roberts Gorden 250 Manual Do Utilizador

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SECTION 9: G
AS
 P
IPING
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SECTION 9: GAS PIPING
A gas meter is connected to the service pipe by the 
gas supply company. An existing meter should be 
checked, preferably by the company, to ensure that 
the meter is adequate for the rate of gas supply 
required.
Installation pipes must be fitted in accordance with 
local and national codes. Pipes of smaller size than 
the heater inlet gas connection should not be used.
Gas lines must meet applicable codes:
United States: Flexible stainless steel gas hose 
(US models) is certified per the standard for 
connectors for gas appliances, ANSI Z21.21/CSA 
6.10 - latest revision.
Canada: Rubber type 1 gas hose (Canadian 
models) is certified as being in compliance with the 
standard for elastomeric composite hose and hose 
couplings for conducting propane and natural gas, 
CAN/CGA 8.1 - latest revision.
9.1 Connections
Connect the heater to the gas supply ensuring that 
the final connections are as follows:
• Gas  supply pipe work is run in medium or heavy 
gauge tubing in compliance with local and 
national codes.
• Meter and service must be large enough to 
handle all the burners being installed plus any 
other connected load. The gas pipe which feeds 
the system must be large enough to supply the 
required gas with a maximum pressure drop of 
1/2" wc When gas piping is not included in the 
layout drawing, contact the local gas supplier.
• An isolating valve and union connection should 
be used and fitted into the supply adjacent to the 
heater.
• A  minimum 1/8" NPT plugged tapping 
accessible for test connection must be installed 
immediately upstream of the gas supply 
connection to the heater.
• For  suspended heaters, an approved metal 
flexible connection between the isolating valve 
and the heater may be used. To reduce 
pressure loss, use one pipe size larger than 
the heater gas connection.
IMPORTANT - The complete installation must be 
purged and tested for gas soundness in accordance 
with local and national codes.
Caution: Do not high pressure (in excess of 1/2 psi 
[14" wc]) test the gas piping with the burner 
connected. Close manual shut-off valve during any 
pressure testing equal to less than 1/2 psi (14" wc).
Check the pipe and tubing ends for leaks before 
placing heating equipment into service. When 
checking for gas leaks, use a soap and water 
solution; never use an open flame.
WARNING
Explosion Hazard
Leak test all components of gas piping 
before operation.
Gas can leak if piping is not installed 
properly.
Do not high pressure test gas piping with 
heater connected.
Failure to follow these instructions can result 
in death, injury or property damage.