10
Eclipse ThermJet Self-Recuperative, V5, Installation Guide 208, 2/4/2013
Figure 3.10 Flame Sensor Installation
Step 7: Piping
Install the piping as shown in the schematics. Refer to
Chapter 3 of the Design Guide No. 208.
Support the Piping
Use brackets or hangers to support the gas piping. If you
have questions, consult your local gas company.
Straight Run of Pipe Before a Metering Orifice
NOTE:
There must be a run of pipe with a straight length
of at least 10 pipe diameters before the burner metering
orifice. Failure to provide this length will result in
inaccurate pressure readings, and poor burner operation.
Pipe Connections
Install a pipe union in the gas line to the burner. This
simplifies removal of the burner.
NOTE:
Flexible pipe nipples will cause inaccurate
metering orifice readings if installed in the burner inlet and
may cause higher pressure drops than equivalent
standard pipe. Consider this when sizing the gas lines.
Avoid Large Pressure Drops
NOTE:
Pressure drop in the piping is a critical parameter.
Make sure that the size of all the piping is large enough to
prevent excessive pressure losses.
Eductor
NOTE:
There should be no direct pipe connection to the
eductor outlet. This may effect eductor performance.
There should be at least a 2 inch (50mm) gap between the
eductor outlet and the exhaust duct or cowl.
Step 8: Pressure Taps
There are two sets of air and gas pressure taps for
differential pressure measurements. In addition, there is a
static air pressure tap that can be used to verify air
pressure.
Valves
Valve Orientation
Install all the valves in such a way that the arrow (if
present) on the valve body points in the direction of flow.
Figure 3.11 Valve Orientation
Gas Cocks
Make sure that the handle of a gas cock is at a right angle
to the valve body when the valve is in the closed position.
This is an important position indicator.
Balancing Valves
A gas balancing valve is either an adjustable limiting
orifice valve or a manual butterfly valve. An air balancing
valve is typically a manual butterfly valve. For more
information, refer to the following sections.
Manual Butterfly Valves
• Install manual butterfly valves in accordance with
Bulletin / Info Guide 720.
Adjustable Limiting Orifice Valves
• Install adjustable limiting orifice valves in
accordance with Bulletin 728/730.
NOTE:
It is recommended that there is a run of pipe with
a length of at least 10 pipe diameters between any flow
altering device and the metering orifice on the burner.
Automatic Butterfly Valve
An automatic butterfly valve is driven by an actuator
(actuator and mounting bracket not illustrated).
• Install the control valve in accordance with Bulletin/
Info Guide 720.
Figure 3.12 Butterfly Valves
Ratio Regulator
Connect an impulse line to the ratio regulator and to the
air supply line.
NOTE:
All settings in this document assume the use of a
Dungs FRG Ratio Regulator. Use of a different Ratio
Regulator may result in improper burner operation.
UV Scanner Location
Flame Sensor;
UV Scanner
Closed
Open
Manual
Automatic
