Deteriorating coffee taste ?

Elcarajillo

Over a few days I found my coffee increasingly unpleasant, varying bitter , sour ,acidic no consistency.?

Checked temperature ,grind changed beans. Ran cleaner through machine, stripped and cleaned grinder all to no avail. Recheck temperature all OK. confused. As temp via PID was working as it should what the hell is wrong.

Thought check temp is adjusting, kept upping thePID temp to get to steam flash off – – 102 no steam ??.

At same setting ran water into hot insulated cup and checked with thermo- probe = 82 deg ??

Removed thermo probe to brew boiler- dead deceased kaput.

As this was late Friday pm a bit stuffed. The only place I have found similar is Espresso shop, but it is for Expobar

I have left a message asking if it is compatible. I tried Ferrari Espresso but they have closed for four days ? possibly stock take ?

Any other suggestions ?

I have resurrected the Gaggia as a stop gap.

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DavecUK

can you remind me of the machine you have?

dfk41

DavecUK It used to be a QM Verona

Elcarajillo

@ DavecUK Sorry forgot important info, yes as @dfk41 IOt is the faithful QM Verona.

12 mm thread, with a black shroud on top. Only info on it is611 107. & 3220. probably obsolete like me !!

DavecUK

Elcarajillo the temperature probes are all standard.As long as you get the right thread size and they have a couple of little thin wires coming from them with a connector that should be standard as well

jrling

Elcarajillo Good to hear of another ‘faithful’ QM Verona. Mine is >10 years old and going strong making 4 cups of espresso/lattes per day. Impressive quality machine (as recommended by DaveC)

Elcarajillo

DavecUK I have a spare for the service boiler, it has the same thread but a different profile, I did wonder if they had different resistances ?

Elcarajillo

DavecUK Well I received the new brew boiler probe and fitted it today.

Unfortunately the Mch is still performing the same.

PID set to 94c, also checked all pid parameters against the BB / your list.

Ran water into preheated insulated cup- temp ap 80 c.

Checked by running water over a mercury stirring probe- same result.

Upping pid temp to 102c no flash off to steam.

As pid is fed 12 v transformer, checked voltage from T/F =11.89 v.

Any thoughts ? PID kaput ?

Also checked overheat T/stat OK

Elcarajillo

@ jrling . I think they are of similar age and usage similar + a couple. (again from Davec recommendation).

Other than regular servicing I did replace the insulation sleeves on both boilers as the originals were beginning to crumble.

DavecUK

Elcarajillo should be working, i have not heard of pids failing in a way where they register the incorrect temperature.I suppose you could double check the offset.

Elcarajillo

DavecUK

Still no luck / change, have run it with long mercury thermometer between boiler and (new) jacket, read steady 100 deg. Brew temp set to 93 deg, water from brew head 85 deg. Adjusting `pid up numbers for temp change but does not change water temp.

I have done a reset of settings as per your numbers, also did reset using ones in QM booklet.

Tried a set off another forum site, no change.

Settings at moment. FO1= 0, FO 2= 6, P1= 1.5, l1= 0.04, D1=1.5, b1=25, P2=1.5, i2=0.00 D2=1.5, B2=6,T1=91,E2=124

E1=15, E2=0, ***=60. (three partial letters come up next, but I cannot read)

Fault in pid ? Why does b/b go to 100 deg and stay steady ?

I have tested all leads and connections for security all OK.

This AM it has thrown up EC.0 , I believe this indicates economy setting.

I have never seen this on the settings before ?

Any thoughts ??

delta76

Did you try another grinder? it sounds like a problem with grinder inconsistency than the machine itself …

Elcarajillo

Definitely not the grinder, completely stripped and cleaned and reset. (Ceado)

Water from brewhead coming out too cool.

DavecUK

Elcarajillo I suppose the PID could have gone bad…can’t think of anything else? Is the group cooler than normal?