Hi guys I descaled a used expobar office lever machine that I bought. It was the first time I did it and I don't know if/when the last person did it.
While doing the operation, while the machine was refilling the boiler I interrupted accidentally by lifting the reservoir (there is a switch at the bottom that is actuated by its weight).

But in any case initially the grouphead was spewing steam and very little water and the Brew pressure would not go past 6 bar with backflush disc.
I turned unit off and drained boiler through water arm and let it cool. Then put fresh water in reservoir. To help get the brew pressure up I have also tightened the adjustment screw behind the drip tray about one full turn tighter then it was before the descale.

Turned the machine back on and the pump refilled boiler just fine. Now no steam from brewhead when lever is actuated. The brewhead is hot to the touch.

But here's the weird behavior:

• - Pressure slowly climbs (it used to jump) to 10/11 bar with backflush disc.
  - On its way up, at around 6/7 bar:
  • - the pump's tone changes (to a sound quieter and calmer than before)
    - water completely stops draining (water used to drain the whole time the lever is actuated) out the OPV return spout.

So espresso comes out with crema just as before, though seemingly not as hot as before and maybe a bit sour. The main indications to me that something is different are:

• - the much quieter pump sound under load
  - the lower pressure reading at the brew pressure gauge
  - the lack of flow draining out of the OPV spout

Any ideas what's wrong? Maybe nothing is wrong and since descaling the machine now working just fine lol

UPDATE: I think most of the issues were from me introducing air into the system. I have attempted to fix this by using a syringe to push water into the pump and also leaving the steam valve open while bringing the machine from cold to operating temp. Now water comes out of the brewhead (~3oz in 12 sec) and there is no excessive steam coming out.

Now the only odd behavior is lower pressure readings on the brew pressure gauges. I used to get 11bar with backflush disc and 1oz/12sec out of the OPV. Now at about the same OPV setting I am getting 10bar with backflush disc and 0.8oz/12sec. (I also notice that as soon as I actuate the lever water flows out the OPV spout into the driptray (I have the plumbable model) at a good rate I would estimate to be 1.2oz/12sec but as soon as the chamber pressurizes the flow rate drops as I mentioned.

Of course as I tighten the OPV all the way I can get pressure to almost reach 11bar but flow is pretty much 0 at the OPV spout under pressure.

So I am thinking is my pump weaker now? Would/could a descaling do this to a pump? I plan to check the mushroom valve and OPV but would debris or scale buildup there cause the issues I am describing?

It sounds like your pump is only producing about 11 bar (if nothing is coming out of the OPV overflow pipe, then the output pressure is the same as input pressure). I don't have much experience with pumps, so I don't know what would be wrong with it - just to check, is it a vibratory pump or a rotary pump?

I think the pump should be producing around 16-17bar by default - when my Leva DB was new there was considerable flow out of the overflow pipe at the default brewing pressures (9-10 bar), I didn't try setting a higher pressure though. It's entirely possible the pump is worn out, but I'm no expert. The following page suggests the same:
http://coffeetime.wikidot.com/vibration ... t-worn-out