Smith HW 420, Инструкция по эксплуатации

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11. The transformer's primary and secondary voltages can be
checked with a voltmeter and the voltages recorded.
ANNUAL CHECKS
12. The Manual Reset High Limit may be checked by recording
the temperature settings, changing the auto reset limit (auto
reset limit may require temporarily jumping the 2 terminals
to bypass the control for higher temperature) and system
controller to a higher set point than the limit itself and running
the boiler. Allow the boiler to shut down on Manual High Limit.
After shut down, the boiler should not fire up until the manual
reset button is depressed and power to the unit is reset. The
auto reset limit and the system controller may be tested in
similar fashion but a shut down on either will not require the
power to the boiler to be reset. Note: If jumper wire was used
be sure to remove it. Return all temperature settings to the
original positions upon completion of test.
13. Redundant Safety Gas Valves may be checked for proper
closure upon shutdown and should stop the flow of gas to the
burner within five (5) seconds of being de-energized.
Downstream of each valve is a smaller leak test valve.
Removal of the plug will allow the connection of a gas
pressure gauge for the purpose of testing - see Figure 1 on
Page 3.
The Redundant Safety Gas Valve first valve seat may be
checked with the boiler off. Close the manual valve located
ahead of the redundant valve. Open the first leak test valve,
note the gauge pressure and verify it is stable. Open the
manual valve allowing gas to flow against the first valve seal.
A steady increase in gas pressure indicates gas is leaking
past the valve seat and the redundant valve should be
replaced.
To check the second redundant valve seat, first disconnect
the electrical supply wire (brown) from TH terminal on
redundant valve. With the firing valve closed, open the leak
test valve downstream of the redundant safety valve, note
the gauge pressure and verify it is stable.
Operate the boiler to call for heat allowing the pilot burner
to light. The first valve seat will open allowing gas against
the second valve seat. A steady increase in gas pressure
indicates fuel is leaking past the second valve seat and the
redundant valve should be replaced.
14. The sediment trap (dirt leg) and gas strainer (if required)
should be inspected periodically for accumulation of foreign
debris that could cause blockage. Gas should be shut off
ahead of the particular device to be cleaned or inspected to
prevent gas leakage.
INSTRUCTIONS FOR TESTING AND MAINTENANCE
DAILY CHECKS
1. Thermometers and temperature gauges should be visibly
inspected on a daily basis for normal operation. These items
should be noted and the differential temperatures recorded
during operation. If the temperature differential increases by
five (5) degrees Fahrenheit (3 degrees C) over the original
installation, a general deliming of the heat exchanger may
be required.
2. Visually inspect main burner flame by viewing upwards
between the burners from the front bottom of the boiler.
Inspect for well-defined blue flames. Check for smooth light-
off.
3. Visually inspect pilot burner for a well-defined flame pattern.
Pilot flame should envelop 3/8 to 1/2 inch (9 to 12 mm) of the
top of the insulated rod on the pilot burner.
WEEKLY CHECKS
4. When satisfied, or on lockout, the main gas valves should
shut off within five(5) seconds. With the system operating,
momentarily turn the system controller down to shut down
the boiler. Listen for valve closure, noting timing. Verify that
there is no voltage present at the valves. Return the system
controller to its normal setting.
5. When a pilot flame failure is detected the boiler should shut
off within four (4) seconds. With the boiler operating, close
the manual pilot shut-off valve, which is located in the pilot
gas supply line.
Note gas valve closure time. Verify that there is no voltage
present at the valves.
6. Flow switch operation is checked by verifying the switch
position during operation. With the cover removed, and water
flowing through the system, observe that the switch closes
the circuit between terminal #1 (common) and terminal #2
(flow closes circuit). When flow stops, this switch will open
the circuit, shutting down the boiler. Note your observations.
MONTHLY CHECKS
7. The flue collector and draft hood are to be visually inspected
internally for any signs of deterioration. Significant corrosion
can signal high moisture content or chemical reactions in the
flue gases. The use of a mirror and light source allows for
easy inspection through the draft hood opening.
8. On optional power vent system, the blower prover switch
may be checked by disconnecting the pressure switch tube.
The boiler will shut down if already operating, or not start if it
is not. Reconnecting the tube will allow the boiler to fire. Note
your observations.
SEMI-ANNUAL CHECKS
9. Burners shall be maintained per the operating instructions of
the Instruction Manual.
10. The heat exchanger is to be visually inspected for build up of
deposits or tube distortion. This is best accomplished when
the burners are removed for their inspection. Light deposits
are to be brushed clear. Heavy deposits or tube repairs
may require removal of the heat exchanger. As well, heavy
deposits may indicate the need for more frequent inspections
and changes in operating parameters. Refer to the Instruction
Manual regarding air supply and corrosion.