# OPV higher than usual



## urbanbumpkin (Jan 30, 2013)

About 10 months ago I adjusted the OPV on my Classic to a static 10 bar using a PF pressure gauge.

I've periodically checked this and it's always been at 10 bar. However I've checked it tonight and it appears to be suddenly about 13 bar.

This leads me to think:-

A) My pressure has suddenly jumped up 3bar

B) My pressure gauge is knackered.

I'm thinking it might be B as I've noticed that the gauge is not filling up with liquid so easily as it used to prior to taking a reading.

Any suggestions?


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## Neill (Jun 26, 2013)

Could the opv be blocked other some scale?


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## jeebsy (May 5, 2013)

Anecdotal evidence (forum posts from knowledgable members) suggests it should be a one time adjustment. Not sure what would cause it to jump. Did you measure it with/without a basket first time? Changed that now?


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## urbanbumpkin (Jan 30, 2013)

I had thought about the blockage or something like that. Would that increase the pressure ?

I last measured it without the basket, which is (as far as I can remember) how I've always measured it.


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## El carajillo (Mar 16, 2013)

You do NOT need a basket in to pressure test or it will leak, try dribbling water into the PF to fill the gauge (does not matter if you over fill.

Insert PF allowing excess water to spill into drip tray. By pre filling it removes air which can cause gauge needle to vibrate. Run and check pressure.

As has been said the pressure setting should remain constant once set.

CORRECTED


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## Neill (Jun 26, 2013)

El carajillo said:


> You need a basket in to create a good seal (not blind), try dribbling water into the PF to fill the gauge and basket (does not matter if you over fill.
> 
> Insert PF allowing excess water to spill into drip tray. By pre filling it removes air which can cause gauge needle to vibrate. Run and check pressure.
> 
> As has been said the pressure setting should remain constant once set.


You actually need to do it without a basket in. If you leave a basket in pressure can leak between the basket and the upper lip of the portafilter.


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## oracleoftruth (Jan 15, 2014)

Basket should be out. Scale seems most likely. It could, as you say, be the gauge.

Can you try it in another machine?


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## urbanbumpkin (Jan 30, 2013)

I have just tried it with the basket in and water does leak out of the sides. (Quite spectacularly!) Pressure does seem still to be high, about 11-11.5.

I have noticed the gauge doesn't fill up so easily with water.

To rule out scale is it just a case of removing OPV valve top and cleaning out?


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## El carajillo (Mar 16, 2013)

I was having a thickness through lack of coffee:exit:


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## oracleoftruth (Jan 15, 2014)

Better to soak the whole thing in descale stuff.


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