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ThermJet, V2, Technical Information, Edition 2.14
Step 3: Ignition System
For the ignition system use:
• 6,000 VAC transformer
• Full-wave spark transformer
• One transformer per burner
DO NOT USE:
• 10,000 VAC transformer
• Twin outlet transformer
• Distributor type transformer
• Half-wave transformer
It is recommended that low fire start be used, however,
ThermJet burners are capable of direct spark ignition
anywhere within the specified ignition zone (see
Datasheets 205-1 through 205-13).
NOTE:
You must follow the control circuits described in
the previous section, “Control Methodology,” to obtain
reliable ignition.
Local safety and insurance require limits on the maximum
trial for ignition time. These time limits vary from country
to country.
The time it takes for a burner to ignite depends on:
• The distance between the gas shut-off valve and the
burner.
• The air/gas ratio.
• The gas flow at start conditions.
It is possible to have the low fire too low to ignite within the
trial for ignition period. Under these circumstances you
must consider the following options:
• Start at higher input levels.
• Resize and/or relocate the gas controls.
• Use bypass start gas. (See the circuit schematics on
the next page.)
