U.S. Boiler Company MegaSteam MST288, Инструкция по установке, эксплуатации и обслуживанию

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I. CHECK THERMOSTAT OPERATION.
Raise and lower thermostat setting as required to
start and stop burner.
J. VERIFY HONEYWELL OIL PRIMARY FEATURES
using procedures outlined in Instructions furnished
with control or instructions as follows:
1. R7284 FEATURES AND CONTROLS
a. The Oil Primary is a microprocessor-
based control. The indicator light provides
diagnostic information for lockout, recycling
and patented cad cell status.
b. Pump Priming Cycle: To facilitate purging
air from the oil lines and filters. The R7284
can be placed in a purge routine by
pressing and releasing the up arrow button
during the Trial For Ignition. “Pump Prime”
is shown on the oil primary display along
with the time left on the Trial for Ignition
(TFI). Pressing the up arrow button adds
a minute to the TFI time for a maximum of
10 additional minutes (press the up arrow
button 10 times). Pressing the down arrow
subtracts a minute from the TFI time (see
Figure 26).
c. Limited Recycle: This feature limits the
number of recycle trials (for each call for
heat) to a maximum of three trials. If the
flame is lost three times and does not
successfully satisfy a call for heat, the Oil
Primary locks out.
d. Limited Reset (Restricted Mode): In order
to limit the accumulation of unburned oil
in the combustion area, the control can
only be reset three times. The reset count
returns to zero each time a call for heat is
successfully completed.
e. All R7284 models have internal "TT Configured
ON" parameters set to "ON".
f. The R7284 has an LCD display and simply
displays lockout and flame status on it.
g. Cad Cell Resistance Check: For proper
operation it is important that the cad cell
resistance is below 1600 ohms.
Cad Cell Resistance (ohms) is measured by
the oil primary. The thresholds are:
< 1600 Ohms Normal operation
> 1600 Ohms Service burner soon
> 6100 Ohms Flame loss, burner shuts
down
> 9999 Ohms Check for broken cell or wire.
R7284 displays resistance in ohms during
Running Mode.
2. CHECK OIL PRIMARY CONTROL
a. Preliminary Steps
•
Check wiring connections and power
supply.
•
Make sure power is on to the controls.
•
Make sure limit control is closed.
•
Check contacts between ignitor and the
electrodes.
•
Check the oil pump pressure.
•
Check the piping to the oil tank.
•
Check the oil nozzle, oil supply and oil filter.
b. Check Safety Features
Safe Start:
•
Place a jumper across cad cell terminals.
•
Follow procedure to turn on
burner.
Burner must not start, indicator light turns
on and control remains in Idle Mode.
•
Remove jumper.
Figure 26: R7284 Oil Primary Terminals,
Display and Function Buttons
Before installation of the
boiler is considered complete, the operation
of all boiler controls must be checked,
particularly the primary control and high limit
control.
WARNING
Due to the potential hazard of
line voltage, only a trained, experienced service
technician should perform the following safety
checks.
This control contains no field-serviceable
parts. Do not attempt to take it apart. Replace
entire control if operation is not as described.
CAUTION
Section VIII: System Start-Up (continued)