PRINCIPLE OF OPERATION
The Series 05-29 system is designed to operate on 24 VAC. To ignite the burner, it is only necessary to set the thermostat to call for heat. When power is supplied to the appliance, the control system opens the main gas burner solenoid valve and provides ignition spark Sparking ceases as soon as a constant flame is present. If the flame is not established during the trial-for-ignition period, the system provides automatic shutdown by de-energizing the gas solenoid valve and going into lockout. The multiple trial-for-ignition model, however, provides for three complete ignition sequences before going Into lockout.
Once the flame is successfully established, electronic flame sensing circuitry (flame rectification) monitors the continued presence of the burner flame. If an established flame is extinguished for any reason, the system will retry for ignition before going into lockout. The number of retries depends on the model selected. Reset after lockout is accomplished by adjusting the thermostat to a setting below ambient temperature for five seconds and then returning to the desired temperature setting.
Models with the optional 15- or 30-second (nominal) purge period allow the combustion chamber to clear itself of any residual gases before each try for ignition. Models without the prepurge option have less than a 1.0 second delay before a single try for ignition.
Inducer Blower Control Option
When the inducer option is selected, the inducer contacts are powered when the thermostat calls for heat The blower shuts off when the thermostat is satisfied. However, when the inducer option is used in conjunction with the postpurge option, the blower stays on for an additional 45 seconds.
MOUNTING
The series 05-29 system is not position sensitive and may be mounted vertically or horizontally using standard hardware; #6 for the model with integral mounting standoffs and #8 for the one with an enclosure.
WIRING WARNINGS:
The Series 05-29 System uses voltages of shock hazard potential and operates in the presence of combustible gas. Failure to observe the following warnings could result in shock, fire, or explosion causing severe injury or death.
- Wiring and initial operation must be done by a qualified technician.
- Before wiring system, manually shut off gas supply and remove power.
- Do not reapply power until all wiring is connected and system is properly grounded.
- Perform Initial Operation before turning on gas supply
PROPER ELECTRODE LOCATION
Proper location of the electrode assembly is important for optimum system performance. It is recommended that electrode assembly be mounted temporarily using clamps or other suitable means so that the system can be checked before permanently mounting the assembly. The electrode assembly should be located so that the tips are inside the flame envelope and about 1/2 inch (1 cm) above the base of the flame.
INITIAL OPERATION
- Check installation, electrode mounting, and electrode gap per previous sections.
- With gas supply manually shut off, apply power to system and advance thermostat above ambient temperature.
- 3 Ensure that a spark is being produced at electrode during trial-for-ignition period. System should lock out after the period. In three try for ignition version, system will automatically recycle two additional times, then lock out.
- Reset thermostat to below ambient temperature.
- Wait 5 seconds, then manually open gas supply and advance thermostat above ambient temperature to recycle system. Check that ignition occurred. Sparking should cease a few seconds after flame has been established.
- If system ignites but fails to hold-in, check input voltage. Also check that system is properly grounded.
For multiple unit installations, ensure that all units are powered by a common supply voltage and that all are correctly polarized and grounded.
