Will this motor work?

[Jimbrowski]

So for the past couple weeks every time my pump came on it would make a squealing noise that would go away in about 10 seconds, and resume its usual whrring noise. A couple nights ago I woke up to it making the squealing noise non stop. I was thinking the bearings had gone out so I decided to take it apart and run the motor by itself to make sure. Motor running by itself made same squealing.

So I thought about trying to replace the bearings but I dont have the tools and the motor looks old enough that it should probably just be replaced. So I went to a pool store around here and based on my current motor (B849) and my pump(Sta-rite Dura-Glas) they gave me the AO Smith Magnatek B854. I got home and was looking at the label when I noticed the service factor of the new motor is 1.10. My old motor had a service factor of 1.5. Will this be a problem? I have only owned this house/pool for a couple months so im not even sure if the B849 was the right motor either.

So how can I tell what motor will be right?

 

[Jimbrowski]

I looked at the impeller part no and here are the specs:

07 - Sta-Rite Dura/Max-E-Glas Impeller, 0.75 HP Full Rated 1.0 HP Uprated (All Series) (C105-138PEB)

Is it bad to have a 1.5hp motor with this impeller? Also, is there a 2 speed motor that would operate with this impeller?

 

[mas985]

I looked at the impeller part no and here are the specs:

07 - Sta-Rite Dura/Max-E-Glas Impeller, 0.75 HP Full Rated 1.0 HP Uprated (All Series) (C105-138PEB)

Is it bad to have a 1.5hp motor with this impeller? Also, is there a 2 speed motor that would operate with this impeller?

Something doesn't seem right. The motor you currently have, B849, is a full rated 1.5 HP (1.5 SF) motor but the impeller doesn't seem to match that. Has the motor or impeller ever been replaced?

Also, do you have the model # of the original pump?

The pump motor rating can be larger than the impeller rating but not the other way around. The only real downside is the cost of the motor.
Also, if the impeller really is a 3/4 HP FR impeller, then you should be able to go with a 3/4 HP FR 2 speed motor as well.

 

[Jimbrowski]

Something doesn't seem right. The motor you currently have, B849, is a full rated 1.5 HP (1.5 SF) motor but the impeller doesn't seem to match that. Has the motor or impeller ever been replaced?

I am guessing the motor has been replaced, but not real sure. The previous owner was a real jerk and provided no information.

Also, do you have the model # of the original pump?

I only know that it is a dura-glas I (just by looking at it and comparing to pics online). However for the life of me I cant find a model number on the thing. Thats when I started looking at the model number of the impeller to try to figure out what the pump is rated for.

The pump motor rating can be larger than the impeller rating but not the other way around. The only real downside is the cost of the motor.
Also, if the impeller really is a 3/4 HP FR impeller, then you should be able to go with a 3/4 HP FR 2 speed motor as well.

[/quote]

I was looking through the manual and found something interesting. They listed that same impeller part for pumps ranging from .5 to 1.5 HP.

http://www.staritepool.com/pdfs/DuraGlasOM.pdf

Im still a little confused about the 2 speed motor part. Let say this is a 3/4 HP impeller.... can I run a 3/4 HP pump at half speed? Seems like it would need to be at full speed for it to have the power to rotate the impeller properly.

 

[mas985]

I think Sta-Rite is playing some games with their pump ratings and service factors. If you look at the max amps for all the pumps that use that impeller, they are all the same so they are all the same motor rating. I cross referenced the motors that are paired with that impeller and they are:

3/4 HP SF 1.65
1 HP SF 1.25
1.5 HP SF ?? (no cross reference but I suspect the SF is less than 1.0)

So I believe that you are safe going with a 3/4 HP 1.65 SF or a 1 HP SF 1.25 two speed motor.

 

[Jimbrowski]

Depending on the price of the 2 speed, I may just go with the B854 that they gave me. Do you see any problem with it, other than inefficiency?

 

[mas985]

A little over dimensioned, but so was the last motor and it shouldn't be all that more inefficient. Motors are fairly efficient over a wide range of loads.