SERVICING
PROCEDURES
Sequence of Operation
Intermittent Ignition Device (IID)
Heaters equipped with the IID system will automatical- ly light the pilot burner first and then the main burner, each time there is a call for heat from the tankstat. Whenever the tankstat calling for heat, the circulator supplied with the heater, will be energized and should be running.
The ignition control module will also be energized to initiate the pilot ignition by opening the first main valve (pilot). At the same time, the electronic spark genera- tor in the module produces a high voltage spark pulse output that lights the pilot burner. If the pilot burner does not light, the module will not energize the second main valve and the burners will not light. Ignition spark continues only until the timed trial for ignition period ends.
Then, the module goes into safety shutdown or lock- out. Lockout
When the pilot flame is established, flame rectification circuit is completed between the sensor and burner ground. The flame sensing circuit in the module detects the flame current, shuts off the spark genera- tor and energizes the second main valve operator which opens the second main valve. This allows gas to flow to the burners where it is ignited by the pilot burn- er flame.
When the tankstat is satisfied, the valve operators are
Start-up Procedures
Filling the System
Fill system with water. Purge all air from the system using purge valve sequence. After system is purged of air, lower system pressure. Flush system before put- ting into operation to ensure that foreign material does not damage pump seals.
Checking the Circulator
Before lighting the heater and after system is filled, make sure that circulator is operating properly. Manual gas valve should be off.
NOTE: Circulator motor supplied with the heater does not require lubrication.
Lighting the Heater
For your safety read carefully before proceeding to light the heater.
CAUTION: Propane gas is heavier than air and sinks to the ground. Exercise extreme care in light- ing heater in confined areas.
For Standing Pilot Models
WARNING: If you do not follow these instructions exactly, a fire or explosion may result causing prop- erty damage, personal injury or loss of life.
A.This heater has a pilot which must be lighted by hand. When lighting the pilot, follow these instruc- tions exactly.
B.BEFORE LIGHTING smell all around the heater area for gas. Be sure to smell next to the floor because some gas is heavier than air and will set- tle on the floor.
WHAT TO DO IF YOU SMELL GAS
•Do not try to light any appliance.
•Do not touch any electric switch.
•Do not use any phone in your building.
•Immediately call your gas supplier from a neigh- bor's telephone. Follow the gas supplier's instructions.
•If you cannot reach your gas supplier, call the fire department.
C.Use only your hand to push in, move or turn the gas control knob or lever. Never use tools. If the knob or lever will not push in, move or turn by hand, don't try to repair it, call a qualified service technician. Force or attempted repair may result in a fire or explosion.
D.Do not use this heater if any part has been under water. Immediately call a qualified service techni- cian to inspect the heater and to replace any part of the control system and any gas control which has been under water.
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