Power supply help for air purifier

[diode]

I have an oreck air95 purifier. It quit on me a couple years ago, my other one broke yesterday which is a similar model so I decided to troubleshoot this one. Neither turn on at all.

I removed the circuit board after checking for power. I am getting household voltage to the board and one side of what appears to be the transformer. I am not getting power to the fuse which is good. I'm suspecting a transformer issue but am not sure how to properly test it. The coil between the film capacitor has continuity at both connections to the board I have voltage to one side of film cap.

 

[Bluejets]

Show photos of the board both sides and check they show detail and correct size before trying to post

 

[diode]

Show photos of the board both sides and check they show detail and correct size before trying to post

I tried putting photos up but keep getting an error.

 

[Martaine2005]

Resize the pictures to about 300kb
Or link to them.

Martin

 

[diode]

 

[Martaine2005]

I am not getting power to the fuse which is good

But you have mains voltage to the board?
I would expect voltage to one side of the fuse if it has blown.

The small yellow disc (MOV) ? Has a crack in it.
The coil thing is a choke and probably just fine but check for cracked solder joints.
How are you checking voltage to the board? Please explain.

Martin

 

[diode]

I have an ac voltmeter, leaving black lead on ground, I'm getting like 38mv at fuse, 117v at power to board and to one leg large 2 leg relay looking device

 

[diode]

It's hard to post better pics but I'll try to get more. I'm trying to lower resolution.

 

[Martaine2005]

Relay looking thing?
Are you talking about the yellow blocks? X2 capacitors.
Use your meter in Ohms or continuity range with no power.
Check the fuse. (across the fuse).

Martin

 

[Bluejets]

Most likely fault is further on.
As in #2, post photo of the board both sides.
Martin, I think the "cracks" are due to the way the photo was taken.
They can also be seen to the right, mid-air.

 

[Martaine2005]

Yes, looks like a 'ghost' crack. Well spotted.

On a side note, does he mean Ground as being Neutral conductor?
If not, use only the live and neutral lines for testing voltage.
Please be careful as your lack of experience is pretty obvious.

Martin

 

[diode]

Yes, looks like a 'ghost' crack. Well spotted.

On a side note, does he mean Ground as being Neutral conductor?
If not, use only the live and neutral lines for testing voltage.
Please be careful as your lack of experience is pretty obvious.

Martin

The fuse is good. I have been using the ground lead on the dmm to the neutral line to the board to clarify. I don't have power to the fuse.

 

[Bluejets]

I don't have power to the fuse.

So the power to the unit is turned off then.

I am getting household voltage to the board and one side of what appears to be the transformer

but this says otherwise.

Best is as Martin said, do any testing without any mains connected and use continuity on the multimeter.
If you don't know how to do that, it will be an uphill battle.
Best look up some videos on how to do.

Btw...your photo shows an inductor, not a transformer.
It is part of the input filter.

What do you get,...... NO MAINS POWER.........when you connect multimeter on low ohms across the fuse F1.

 

[diode]

 

[Martaine2005]

Nice photo.
Can you post one of the solder side too?.

Martin

 

[diode]

Yes, I verified power to the fuse and whatnot, I had a bad connection earlier, so I have power to the board, I have power going out of the yellow red and green wires to the fan and ionizer. So I believe the return black wires are what control the fan, etc. It has the touch buttons which are the coiled devices on the board. I'm not sure how to trigger those.


My other purifier failed the other day while running, just shut off and now is not responding to pressing buttons.

 

[diode]

 

[diode]

How do I test the yellow rectangular caps on the board? I will say the ion function never worked when I had it working, there's an led for it and an ionization element but it never lit up when pushed.

 

[Bluejets]

Looks like the 335k grey cap on the rear may be responsible for setting up the voltage as well as a couple of other components there (zener)
Looks like possible joint problem with one, maybe just the light.
Don't know why the board is black where the cap vias come through near R11 and R12.
One edge of the cap there appears to be a via that has damage (cooked or bad soler)
Caps need to be removed to test with a capacitor or component tester.
Wouldn't be too concerned about the two yellow caps, as I said before just a filter.
Cannot see what is under the grey cap nor what (if any) number on T1 which will be a major player in power switching.
Possible micro (U1) on the back was zapped or damaged and no way to test that.
Many other surface components....not really meant to be repaired overall.

 

[diode]