UTICA BOILERS UB125, Инструкция по установке, эксплуатации и обслуживанию

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The differential air pressure switch is a safety
device which will prevent the boiler from firing
if there is an air intake, boiler heat exchanger
or vent blockage.
The following steps and diagram indicate the
location of the connection points required to
measure the offset pressure using an Inclined
Manometer or a Differential Pressure Gauge.
Only one device is required to measure the
offset pressure.
1. Turn off service switch, or lower thermostat
setting.
2. Remove vinyl caps from Tee.
3. Install testing lines as shown to Inclined Ma-
nometer or Differential Pressure Gauge with
the ability to read 0.01” to at least 6.0” w.c.
4. Turn on service switch and set thermostat
to call for heat.
5. If manometer readings do not correspond
to the chart at right, check for possible
causes:
• Blockage or moisture in suction lines to
switch.
• Blockage or moisture in orifice installed
in suction lines to switch.
• Blockage in air intake or vent pipes.
• Undersized air intake or vent pipes.
• Loose blower wheel on motor shaft.
• Incorrect pressure switch or pressure
switch setpoint.
• Gas valve out of adjustment.
6. When the pressure reading corresponds to
the chart at right and the pressure switch is
operating properly, remove the testing lines
and reinstall the vinyl caps to the Tee and
3-way connector.
Boiler status Differential Pressure switch contacts
Not Running 0”
3.5” Closed
0.5” Open
Running Without
Blockage
(Approximate mini-
mum vent lengths)
1.00” for Model 125
3.5”
0.5”
Closed
Closed
1.50” for Model 150
1.50” for Model 175
2.00” for Model 200
Running With
Blockage
Greater Than or Equal
To Setpoints
3.5” Open
0.5” Closed
Locations of the connection points required to check
the differential air pressure.
dIFFEREntIal aIR pREssuRE sWItcH cHEcK
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