Blower motor popping circuit breaker

[dallan1]

My blower motor will pop the push button circuit breaker after a few minutes. When I reset it will run again for awhile and then pop. I dont see any obvious issues, any suggestions before I dig into this problem?

 

[dingbat]

Resistance within a circuit increases the current.

Check your power and ground connections

 

[Chris1956]

Push button circuit breakers do wear out. Blowers can also get corroded. A resistance check on the blower circuit can tell you what is wrong. Alternatively, you could replace the circuit breaker with a fuse, rated for the current draw of the blower and see if it blows.

 

[dallan1]

Push button circuit breakers do wear out. Blowers can also get corroded. A resistance check on the blower circuit can tell you what is wrong. Alternatively, you could replace the circuit breaker with a fuse, rated for the current draw of the blower and see if it blows.

Thanks for your input, how do you perform the resistance check?

 

[dallan1]

Resistance within a circuit increases the current.

Check your power and ground connections

Thanks.

 

[Fed]

Resistance within a circuit reduces current.
Check for short circuits in wiring and blower motor.

 

[dallan1]

Push button circuit breakers do wear out. Blowers can also get corroded. A resistance check on the blower circuit can tell you what is wrong. Alternatively, you could replace the circuit breaker with a fuse, rated for the current draw of the blower and see if it blows.

Hello- I went to the boat this weekend and the blower is a Detmar 7-5-1R and says 12VDC 3.5amps, but also says 6amp fuse. I know the push button breaker is only 5amps, can I just replace that with a 6amp breaker or do you think there is still a short somewhere? Thanks.

 

[Chris1956]

There is no way to tell if there is a short in the circuit, blower or if the circuit breaker is bad. Presumably the blower worked for years with the 5 A circuit breaker. You should either measure the resistance of the circuit and solve for amperage, or replace the circuit breaker, whichever is easier. You would need a decent ohmmeter to read the resistance accurately.

Ohms law says that the blower circuit should have a resistance value of 3.43 ohms, for a 3.5A draw. A 2 ohm resistance value means the blower circuit is drawing 6A. A 6a draw probably means the circuit is shorted or the blower is shorted.