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Page 26

Copper Brute B4 Volume Water Heaters

Page 27

The following tools are required for proper 

service and problem diagnosis of the heater and 

heating system. 
1.      Gas pressure test kit with range from 0 to 14 

inches (0 to 356 mm) W.C.

2.      Electric meter(s) with the following ranges:
         a. 0 to 500 volts VAC
         b. 0 to 2000 ohms ()
         c. 0 to 20 microamps (mA)
         d. 0 to 50 millivolts (mV)
3.      A pressure gauge and a thermometer with proper 

ranges for heater operation.

5.2.1  Heater Does Not Come On 
Important: Disconnect power to the heater 

or pull the RED wire off the transformer secondary 

before removing or replacing any component or wire 

connection. 

 

If power is not disconnected, jumpering gas valve 

or accidental grounding of the wire harness, or 

component terminals to the heater frame or jacket 

could cause the ignition control fuse to blow or 

may cause the heater to fire, resulting in injury or 

property damage.

1.      Make sure the heater has been properly installed.
2.      Make sure the pump is not airlocked, clogged or 

otherwise inoperative.

3.      Make sure the gas valve is on and there is gas 

pressure in the line.

4.      Check all electrical connections and wiring. 

Finding a loose connection or a charred wire can 

save a lot of time and money.

5.      Check the fuse inside the black, twist-lock fuse 

holder. If it is burned, replace it with a 2-amp 

fuse (Part No. E0084400). If there is a short, the 

cause of the short must be found and repaired. 

Do not jumper or bypass the fuse.

6.      Make sure the electrical circuit to the heater is 

on.

7.      Make sure the toggle switch on the right side of 

the heater is on.

8.      Make sure the temperature control is set high 

enough to call for heat.

9.      Make sure the manual reset on the safety controls 

(e.g., low water cutoff, hi-limit switch, etc.) has 

not tripped. If it has, reset it.

If the pump is circulating water, and the rest of 

these items check out all right, the trouble could be in 

the heater control system.

 

Label all wires prior to disconnection when servicing 

controls. Wiring errors can cause improper and 

dangerous operation. Verify proper operation after 

servicing.

NOTE: Keep the pump running.
Testing the transformer requires an AC voltmeter 

with a 50 volt (V) range. Test the transformer using the 

following procedures:
1.      Clip a lead from the voltmeter to the yellow wire 

terminal on the transformer.

2.      Touch the other lead to the red wire terminal 

(see Figure 37). The voltmeter should read 24 to 

28VAC. 

3.      If the voltmeter does not show voltage, check the 

electrical power supply.

4.      If the voltage is less than 20VAC, the electrical 

circuit to the heater may be supplying less than 

103VAC. This could be due to high pump load or 

air conditioners or other appliances on the circuit.