Electrical Relay

General

The electrical relay is used to supply power to the Ignitor control board (Ignition control printed circuit board) and fuel (Kerosene) oil solenoid. When the burner switch is turned “on” and all the safety switch requirements met (Like fuse 10 AMP, Thermostat, flow switch) the relay provides 12 volts to the Ignition control board, circuit, fuel oil solenoid and ignition coil. The circuit is continuously grounded, so the Ignition control board and fuel oil solenoid immediately activated and supply power to Burner Ignitor system. Activation of the Ignition coil and Fuel oil solenoid is control by the Temperature control, which grounds their respective circuits at the proper times.

Service

A malfunctioning relay can result in starting or operating burner difficulties. The relay and related wiring can be tested as follows.

1.        Disconnect the relay connector plug from the relay.

2.        Connect black lead of VOA meter to a chassis ground location. Connect red lead to the #85 terminal in relay connector (see Figure above). Set meter to test resistance (Rx1). Turn engine key ignition switch from “off “ to “on”. Meter should indicate continuity (ground circuit is completed) for 1 to 3 seconds. Turn key switch back off.

a.         Clean the connection and check wiring if circuit was completed.

3.     Set meter for DC voltage. Touch red tester lead to the #30 terminal in relay connector. A reading of 12    

        volts should be indicated at all times.

4.        Connect red lead of meter to the #86 terminal in relay connector. Turn key switch to the “on” position.

Battery voltage should be present.

a.        No voltage is present indicates a problem in the wiring or at connector.

        b.    If voltage is present, the wiring to the connector is good. Turn ignition key switch “off “ and  

               proceed to test 5 to test the relay.

5.        Connect an ohmmeter (Rx1 scale) between the #85 and  #86 terminals in the relay. There should be

Continuity.

6.        Attach ohmmeter leads to the #30 and #87 terminal in relay. Initially, there should be no continuity.

Using a 12 volt power supply, connect the positive (+) lead to the #86 terminal and touch the negative (-) lead to the #85 terminal. When 12 volts is applied, the relay should activate and continuity should exist (circuit made) between the #30 and #87 terminals. Repeat the test several times. If, at any time the relay fails to activate the circuit, replace the relay.