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Scoffcruddle
04-11-2014, 11:52 AM
Been having trouble with fan motors on a b4 unit,after 2 replacement 240v motors failed I decided to use a 3phase motor,all worked well its been in use for 4months mostly 24hrs a day,then the motor seems to have overheated and died,is it just bad luck and these motors are cheap? (Polestar)

The 3phase motor came with the option to wire star or delta (wired it up star) it also has two purple wires,I believe these are for the thermal overload,how should they be wired in?

I do have a wiring diagram but because I've used a 3 phase fan motor it isn't relevant.


Thanks Scoff.

monkey spanners
04-11-2014, 06:43 PM
The purple wires should be wired in series with the pressure switches and overloads. The white, brown and black get joined together and the three phases go to red, blue and yellow.

I would be tempted to replace the fan blade to rule out it being out of balance and over loading the motor.

Does it pull the correct current? Is the condenser clean?

B4 condensers should have a 6 pole 180w motor which is easy to confuse with a 4 pole 120w.

I haven't had any failures with the Polestar motors, but would say that Remco or Lemac motors are better quality, think FSW does Remco.

If you are 'rescuecow90' on youtube you have your profile set to block replies to your questions. :)

Scoffcruddle
04-11-2014, 07:30 PM
The purple wires should be wired in series with the pressure switches and overloads. The white, brown and black get joined together and the three phases go to red, blue and yellow.

I would be tempted to replace the fan blade to rule out it being out of balance and over loading the motor.

Does it pull the correct current? Is the condenser clean?

B4 condensers should have a 6 pole 180w motor which is easy to confuse with a 4 pole 120w.

I haven't had any failures with the Polestar motors, but would say that Remco or Lemac motors are better quality, think FSW does Remco.

If you are 'rescuecow90' on youtube you have your profile set to block replies to your questions. :)


Thanks.

It figures now the fan motor is slightly out,noticed today when I fitted the new motor.

I took the motor apart and the rear bearing has gone,it's also worn the housing,so vibrations will have caused this.

Where is best to get new blades?

Are you the chap on YouTube? Great clips:cool: do you travel up into lancs?could do with someone decent up here.

Cheers scoff.

monkey spanners
04-11-2014, 09:13 PM
Blades are a bit difficult to get, last time i needed one they were obsolete from the Prestcold agent. I was looking into getting one made by Solar but the customer replaced the system.

The other option would be a guard mounted axial fan like the later B4 condenser models used, but mounting holes and fan aperture size would need checking (have not tried to see if they fit)

I'm happy to travel if customers are happy with the cost to get me there. Most of my customers are within 60 miles but i have a few nearer 150 miles who will call me in for the more specialist problems. Yes thats my channel on youtube :)

Scoffcruddle
04-11-2014, 09:37 PM
Blades are a bit difficult to get, last time i needed one they were obsolete from the Prestcold agent. I was looking into getting one made by Solar but the customer replaced the system.

The other option would be a guard mounted axial fan like the later B4 condenser models used, but mounting holes and fan aperture size would need checking (have not tried to see if they fit)

I'm happy to travel if customers are happy with the cost to get me there. Most of my customers are within 60 miles but i have a few nearer 150 miles who will call me in for the more specialist problems. Yes thats my channel on youtube :)

My motor is guard mounted (clamped by both sides of the guard).

I don't mind paying for decent work or transport costs,it's when you get someone land and you know more about the job than them.

As you do lots of work on farm tanks what's the one that you don't ever see?:)

I'm after another tank but want a reliable one.

cadwaladr
05-11-2014, 02:32 AM
The metal fan blades are prone to going out of balance normally caused by people being lazy and using big hammers etc to remove it from the motor,one wholesaler I use stocks a plastic fan which is better than the metal type,thermofrost and they have a branch in mcr

monkey spanners
05-11-2014, 11:05 AM
My motor is guard mounted (clamped by both sides of the guard).

I don't mind paying for decent work or transport costs,it's when you get someone land and you know more about the job than them.

As you do lots of work on farm tanks what's the one that you don't ever see?:)

I'm after another tank but want a reliable one.

Yeah the early ones had a two piece guard, motor and blade, the later ones all come as one assembly which is the axial guard mount one i was thinking of.

A bit like this, it shows the different design but is another make of equipment,

https://www.youtube.com/watch?v=TNgQejlaZqc&list=UUxJXtG4fhbM7gE3FRcissrQ


A lot of reliability comes down to instal and siting of equipment. It is also good to pick a make that has a dealer near by. But having said that I would pick Serap, Fullwood/Packo, or Fabdec. I look after a DeLaval and a Roka which also are ok but parts can be a pain for me to get.
I am not keen on Mueller, i don't think the wash is very good with the fixed spray head and technical advice and spares can be hard to get as the agent thinks he should be the only one working on them...

Be aware that any second hand milk tank may be running on R22 which will not be available after the end of the year, so you could buy yourself some problems if you are not careful. You can still use a system with R22 but you will not be allowed to move it or have any work done on it requiring removal of the refrigerant, such work would require the refrigerant to be changed to another type, which is not as simple as it sounds.

monkey spanners
05-11-2014, 11:42 AM
The metal fan blades are prone to going out of balance normally caused by people being lazy and using big hammers etc to remove it from the motor,one wholesaler I use stocks a plastic fan which is better than the metal type,thermofrost and they have a branch in mcr

Climate have stopped doing the plastic blades will have to try thermofrost next time, think the plastic ones are 15", i think the B4 condenser is the one with the 180W motor and the 18" or bigger blade.