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Page 28

Copper Brute B4 Volume Water Heaters

Page 29

2.      If the voltmeter reads voltage, the safety fuse and 

the fusible link are good. 

3.      Replace the fusible link when an open circuit is 

detected. An open fuse line indicates overheating 

in the flue collector or compartment.

4.      Check for leaks of the flue collector, vent pipe, 

gaskets, and all connections.

5.      Check the flue pipe for blockage.
6.      Check heat exchanger fins for partial sooting.

To test the fuse:

1.      Clip a lead of the voltmeter to the grounding 

terminal.

2.      Touch the other voltmeter lead to the 24VAC 

terminal on the ignition control.

3.      If there is no voltage, replace the fuse. A blown 

fuse is usually an indication of a short in the 

24VAC circuit. It is important that the cause of 

the short be found and repaired. Do not jumper or 

bypass the fuse.

 

The ignition control and igniter operate on 120V 

power. Keep this in mind while servicing the heater, 

and take care to avoid electrical shock.

The ignition control provides power to the pilot, 

opens the gas valve when there is a call for heat, and 

senses when a flame is established. To test the ignition 

control for spark ignition:
1.      Clip one lead from the voltmeter to the yellow 

wire terminal on the transformer.

2.      Touch the other voltmeter lead to the red 24V 

terminal on the ignition control. 

3.      If the voltmeter reads voltage, the temperature 

control and the manual reset hi-limit switch are 

not keeping the heater from firing.

4.      Make sure the pilot burner is positioned next to 

the main burner (see Figure 40) and there is no 

soot or dirt on it.

5.      Make sure the electrode (part of pilot assembly) 

is clean, the terminal connection is tight, and the 

ceramic insulator lead is at least 3/8 inch (9.5 

mm) from the heater chassis and other metal 

parts. 

6.      Check for proper spark gap.

Connections must be tight, and silicone rubber 

boots in place. Bare metal parts at the base of the 

manifold bracket must be at least 3/8 inch (9.5 mm) 

from other metal objects. To test the ignition lead:
1.      Turn the control panel switch to on.
2.      Make sure the temperature control is turned far 

enough to call for heat. There will be a loud 

clicking noise indicating the pilot electrode is 

sparking. 

3.      If no sparking is heard, pull the ignition lead 

from the ignition control and hold the bare 

terminal 1/8 to 3/16 inch (3.2 to 4.8 mm) from 

the ignition stud with a pair of insulated pliers 

(see Figure 41).

4.      If a spark does not jump the gap, replace the 

ignition control.

NOTE: The ignition control cannot be repaired 

in the field. If it does not operate properly, replace it.