Gas Train And Controls; Venting Of Gas Valves And Pressure Switches; Burner - Camus Hydronics DRH300 Installation, Operation And Service Manual

rating plate. The opposite will occur with tall stacks where
drafts exceed negative 0.15"W.C.
•
If the appliance will not light off it will be necessary to
adjust the low fire as explained in the detailed start-up
procedure.
3.9

GAS TRAIN AND CONTROLS

Figure 13: Typical Gas Train (DR2000 – 3000)
Figure 14: Typical Gas Train (DR 3500 – 5000)
Differential
High Gas
Metering
Switch
Valve
Firing
Valve
Fan
Inlet
3.10 VENTING OF GAS VALVES AND PRESSURE
SWITCHES
The optional gas pressure switches may be provided with
threaded termination points to be vented to the atmosphere,
outside the building. The gas pressure regulation function is
provided by the ratio gas valve which does not require
installation of a vent line. The optional gas pressure switches
are installed in the upper chamber of the appliance. Threaded
vent line connections from components requiring an external
vent line are provided on the component. These vent line
connection points may be accessed by removing the top of the
appliance. Local codes may require the routing of these bleeds
and vents to the atmosphere, outside the building. Proper
routing of vent lines to the atmosphere from the factory
supplied termination points is the responsibility of the installing
contractor.
16
Low Gas
Switch
Control
Valve Regulator
Valve
3.11

BURNER

This appliance uses a single cylindrical burner installed
vertically into the cavity located in the center of the heat
exchanger. There is a unique burner for each one of the
18 models.
Burners MAY NOT be interchanged between different
Btu/hr input models. The burner consists of a round
mounting flange welded to a mixing tube. The top side of
the mixing tube provides the transition which mounts the
discharge from the combustion air fan into the burner. The
bottom side of the mixing tube is attached to a stainless
steel perforated sleeve. This stainless steel sleeve is
covered with a knitted alloy material that forms the burner
port surface. The knitted burner port material is a metal
fiber material which is a unique alloy of iron, chrome,
aluminum and several rare earth metals. This alloy is
designed to operate stress free as a burner port surface.
The burner port surface can sustain operation from a blue
flame down to infrared conditions as the burner input
varies. In order to maximize the operating life of the
burner, the normal operating mode for the Dynaforce® is a
blue flame. Infrared operation will occur only if air to gas
adjustments are incorrect. If infrared operation is noted the
Main
cause must be corrected.
Manual
Valve
Model 300 – 2500: Direct ignition is standard. The burner
mounting flange provides a flame view port and the
mounting point for the hot surface igniter and the flame
sensor.
Model 3000 – 5000: Proven pilot ignition is standard. The
burner mounting flange provides a flame view port, the
mounting point for the hot surface igniter, a connection to
the pilot tube and the flame sensor.
The hot surface igniter and flame sensor are removable
from the burner mounting flange without removing the
burner assembly from the heat exchanger.
Never use an open flame (match, lighter, etc.) to check
gas connections.
Figure 15: Burner