Roberts Gorden 225 250 Manual Do Utilizador

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COMBAT
®
 UHA U
NIT
 H
EATER
 I
NSTALLATION
 O
PERATION
 
AND
 S
ERVICE
 M
ANUAL
14 
SECTION 8: GAS PIPING
It is important that the gas supply pipe and the 
electrical connections do not support any of the 
heater’s weight.
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.
8.1 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" w.c. 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.
• Do not high pressure (in excess of 1/2 psi 
[14" w.c.]) test the gas piping with the burner 
connected. Close manual shut-off valve 
during any pressure testing equal to or less 
than 1/2 psi (14" w.c.). Failure to follow these 
instructions can result in property damage.
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.
Figure 9: Gas Connection
WARNING
Fire Hazard
Connect gas supply according to Figure 9.
Gas can leak if not installed properly.
Failure to follow these instructions can result in death,
injury or property damage.
Fire Hazard
Connect gas supply according to Figure 9.
Gas can leak if not installed properly.
Failure to follow these instructions can result in death, 
injury or porperty damage.
Gas Shut-off Valve
Drip Leg
Cap
Union
Connection
Option B:
Medium or Heavy
Gauge Pipe
Gas Connector
Option A:
Stainless Steel
Flex Gas
Connector
Do not bend flexible 
gas connector 
sharply.
• Hold gas nipple 
securely with pipe 
wrench when 
attaching the flex gas 
connector.
• Do not twist flexible    
  gas connector.
• Ensure all 
joints are 
gas tight.