Finned copper tube gas boilers & water heaters – Boiler Manual
31
NATURAL GAS: Optimum results are obtained when the boiler/
water heater is operated with the manifold pressure(s) set per Table
19. The manifold pressure should not vary outside these ranges.
Each gas valve pressure regulator has been preset at the factory.
If adjustment is necessary the following steps must be followed:
1. Remove the 1/8 in plug(s) from the manifold pressure valves.
Connect
20 in
,
508 mm
WC manometers to them, see Figure
18.
2. Remove the regulator adjustment screw cap from the safety shut
off valve(s).
3. Rotate the regulator adjustment screw clockwise to increase the
manifold pressure, counterclockwise to decrease it.
4. Replace the regulator adjustment screw cap and manual shut off
valve pressure tap plug.
Never force the regulator adjustment screw beyond
the stop limits or damage to the regulator will occur!
PROPANE GAS: Optimum results are obtained when the boiler/
water heater is operated with the manifold pressure(s) set per Table
19. If the manifold pressure is off by more than 5% adjust it according
to steps 1 through 4 above.
Airflow Adjustment
1. Remove the upper front jacket panel.
2. Connect both sides of a manometer to the pressure switch tee,
Figure 18, going to one of the pressure switches.
3. With the unit operating at high fire the differential pressure should
be between
0.6 and 0.8 in
,
15 and 20 mm
WC. Do not change
air pressure in lower stages.
4. To fine tune the air settings once the upper front jacket panel is
installed, remove the plastic plug(s) on the upper front jacket
panel. Use a Phillips screwdriver to rotate the screw(s) to obtain
the CO
2
and CO readings in the INPUT RATE section above.
CONTROL DESCRIPTION
Boiler Thermostat
If a thermostat is to be used to control the boiler always follow the
instructions included with the thermostat. Proper location of the
thermostat will ensure efficient trouble-free operation of the boiler.
Mount the thermostat to an inside wall at a height approximately
five feet above the floor.
Avoid placing the thermostat in areas that will not provide an accurate
measurement of the room temperature. Locating the thermostat
behind a door, in an alcove, close to a source of thermal radiation
or in a drafty area will cause poor or sporadic heating.
For a thermostat that employs an adjustable heat anticipator, adjust
the anticipator to match the current measured in the thermostat
circuit. An increased anticipator setting may be necessary if the unit
cycles frequently. If the room temperature over-shoots the thermostat
setting, reduce the anticipator setting.
Operating Control
The preferred control setting for potable hot water is
130°F
,
54°C
.
The operating control should be set to the lowest setting that will
satisfy the consumer's needs.
Setting the thermostat or operation control too high
can result in scalding resulting in severe personal injury!
High Limit (Aquastat)
The high limit is located in the left side area of the boiler/water
heater. A remote capillary bulb is run to a well on the outlet side
of the supply header. The high limit can be reset by depressing the
black rubber plug in the front top jacket panel.
The water heater high limit should be set a minimum of
20°F
,
11°C
higher than the operating control. Refer to the HOT WATER
SUPPLY section for the proper supply water temperature.
Flow Switch
A flow switch is provided in the water outlet piping to prevent the
boiler/water heater from firing without adequate water flow through
the heat exchanger.
Low Water Cutoff
If the boiler is to be installed above radiation or if required by other
codes or regulations, install a low water cutoff in appropriate piping.
Wire the switch and any external controls in series to the "Interlock"
contacts in the junction box (see the attached Connection Diagrams
for details). Ensure that the low water cutoff device(s) will function
properly.
Flame Sense Module
The flame sense module is located on the control tray. It is an
intermittent pilot control device that controls the pilot gas flow,
spark energy to ignite the pilot gas and the main valve(s) once pilot
ignition has been proven.
Two flame failure alarm terminals are provided on the flame sense
module. For CSD-1, these terminals will be utilized to shut the unit
down in case of flame failure. The two terminals will be connected
to a lockout control module located on the control tray under the
flame sense module. This lockout control module contains a magnetic
latch relay that requires manual reset when de-energized. To reset
after flame failure, push and release the momentary contact switch
located within the front control panel.
