Want to replace a 2-speed motor with a single speed motor

[beezar]

Hi everyone,

I have a 2-speed pump powering a waterfall that just burnt out. Don't ask me why the original owners had a two-speed motor wired only for one-speed for a waterfall... The motor makes a hum, but does not run. The impeller turns freely, and I tried changing the capacitor (the original capacitor was bulging), but still just a hum. So I think the motor is burnt out. (Unless it could be something I'm not thinking of?)

So I want to change it to an equivalent one-speed motor. The pump is a Hayward Tristar Pump model # SP32102EE (advertised as a 1 HP 2-speed pump), with the following stats:
Emerson motor 1.85/.22 THP; 1.0/.12 FRHP / 1.85 SF, and I'm pretty sure it's wired to the high speed.

Should I just get a 1.0 HP motor? I know that you multiply the SF by the HP to get the THP, but I'm still a bit confused on what exactly I should order, because the SF and therefore THP should vary, but they only seem to advertise 1 HP or 1.5 HP or 2.0 HP motors without any mention of SF or THP. Thanks!

 

[JasonLion]

Re: Want to replace a 2-speed motor with a single speed moto

The starter switch might be stuck.

 

[carolina pool]

Re: Want to replace a 2-speed motor with a single speed moto

What you have is FULL rated or equivilant to a 1 1/2 hp MAX rated. Just about everything advertised is a MAX rated pump. If it has NSF approval, it will be FULL rated.

 

[bigdav160]

Re: Want to replace a 2-speed motor with a single speed moto

The starter switch might be stuck.

That's very likely since the OP said the cap was bulging. Remove the rear cover, unbolt the fan and make sure the contacts on the starter switch are not stuck together. This is a centrifugal switch that charges the cap.

 

[beezar]

Re: Want to replace a 2-speed motor with a single speed moto

Ok, thanks for the replies. Being a noob at this, I'm not sure what the starter switch looks like, let alone if it is stuck. I've looked around and sort of can guess what it is... posted some pics below.

First pic is with the back of the motor cover removed showing the motor shaft. You can see some springs behind that black disk, and I'm assuming that assembly is the starter switch? You can press the disk in (and metal contacts are made) and when you release it, the springs push the disk back out. The 2nd pic below is without pressing in the disk, and the 3rd is with pressing the disk.

Well, at least this part didn't seem to be stuck at all...

 

[beezar]

Re: Want to replace a 2-speed motor with a single speed moto

What you have is FULL rated or equivilant to a 1 1/2 hp MAX rated. Just about everything advertised is a MAX rated pump. If it has NSF approval, it will be FULL rated.

Ok, so my pump has a THP of 1.85, so if I order a 1.5 HP pump as advertised, if the starter switch is indeed not stuck, that would be ok even though the THP is 1.85? Thanks.

 

[jblizzle]

Re: Want to replace a 2-speed motor with a single speed moto

The switch is the thing with the spring on it.

The service horsepower of the motor needs to be at least that of the impeller. If the original was 1.85, you should get a motor at least that or the motor may be overworked and overheat. Or get a smaller impeller as well as a smaller motor.

Posted from my Droid with Tapatalk ... sorry if my response is short