Deep Well Jet Pump Amp Draw Seems High

[Blueoval78]

Hello everyone, I recently went through a power outage where I tried to run my 110 volt 1/3 hp convertible jet pump on my 3000 watt generator. When the pump tried to start, it ran slowly and smoke came out of the motor. It eventually got up to speed but since then it has the burnt smell when it runs on normal house power. The motor has 8.2 amps under SF on the tag so I figured my generator could easily handle the pump thinking start surge might be double or triple that at most. Last night I put a clamp meter on the hot wire and it runs at 10.2 amps with a 63 amp start peak! No wonder my generator couldn’t handle it. My question is, does this amperage draw seem normal for a 1/3 hp motor running a convertible jet pump on a 45’ deep well? The pump appears to be running perfectly normal. Thanks in advance for responses.

 

[Valveman]

If the Service Factor Amps SFA is 8.2, then the motor should never draw more than 8.2 amps. 6 times 8.2 or 49 amps would be normal start up amps for a motor like that. And start up amps will be higher if the start cap is blown, which is usually where the smoke comes from.

 

[Sponsor]

 

[Blueoval78]

If the Service Factor Amps SFA is 8.2, then the motor should never draw more than 8.2 amps. 6 times 8.2 or 49 amps would be normal start up amps for a motor like that. And start up amps will be higher if the start cap is blown, which is usually where the smoke comes from.

Thanks for the response. If I am running over 10amps, should I bother replacing the start cap or just get a new pump? Would there be a negative impact to upgrading to 1/2hp? Can I replace just the pump or do I need to also replace the hardware at the bottom of the well?

 

[Valveman]

A bad start cap would just keep the pump from starting, not make it pull high amps after start up. Probably a bad motor or bearings. The jet assembly at the bottom has to match the pump size, might work, might not. 1/2HP is more common. Not sure you can even get 1/3HP anymore.