i hate threads that dont have a solution. turns out descale did the trick. thanks

WLL installs the thermosyphon restrictors on the upper tube, boiler side. My Expobar Office Lever has had similar issues. I am able to monitor brew temp via Erics Thermometer. My machine was fine for the first 6 months and then it started having daily thermosyphon stalls. It would heat up to approx 190 and then the temperature would plummet if I didn't run water through the group head or wiggle the portafilter. Once it reached brew temp it was stable and would not stall until the next day. I ended up replacing the opv, de-aerator and pump. This remedied the situation for a few months but unfortunately my machine is back to stalling again.

wow, i sent pictures, checked and double checked and was told the the restrictor was installed on the upper tube brew group side not boiler side. I could not get the boiler side nut off. It seemed like i would damage something if i tried any harder. So i guess its possible the restrictor is still in there. the machine is getting up to 195 after descale but slow to recover so its possible the restrictor is still actually in there. Did you remove that tube yourself and see the restrictor?

heres the quote. so which is correct?

Thank you for your email. The plate is located right behind the group head. Inside of the machine, the upper large copper pipe has the plate right at the group head. You only need to remove the pipe. You do not need to remove the group head from the machine.

Tech Support

I did remove the pipe myself. It was very difficult. I thought I was going to break it. If I recall correctly, I had my wife hold the machine so I could get a bit more leverage and was very careful to stay prepared for any slipping once it did break free. The restrictor was on the boiler side NOT the grouphead side. It is possible that they install it differently now. I purchased my machine in July 2012. WLL tech support told me it would be on the boiler side. I am betting you have a restrictor if your machine is at 195 with slow recovery. My understanding is that Expobars are known for running very hot (i.e. 212-214) and requiring lengthy flushes without the restrictor. I am actually thinking about removing mine to see if it might be contributing to my thermosyphon stalls. Let me know if you have any questions.

i have to admit i was always a bit suspicious about the location because in the video the restrictor looked a bit too big for the grouphead side but i thought i was talking to the experts. frankly i am fairly happy with the coffee temp and taste after the descale. i may have to remove that pipe altogether at some point just to satisfy my curiousity and to see how the machine performs. damaging it will definitely be a concern though. thanks for the info.

I am curious, what exactly did you do when you performed your descale? Did you run descaler from the water reservoir?

yes, and i ran some vinegar through it. working even better today.

Could you please give me instructions on exactly what you did? I have read so many conflicting ways to descale. Did you have any trouble removing the vinegar smell/flavor?

Properly removing boiler fittings which are tight requires two wrenches opposed to each other. You squeeze the wrenches together without having the hold the machine. The applies all your force to the pipe's fitting without risking damage to the boiler. Eric S posted a photo of this in a thread somewhere here on HB.

Having someone hold the machine or boiler while you attempt to loosen a fitting attached to a brazed boss on a boiler is a recipe for subsequent, expensive repairs.

If it is a fitting screwed into the boiler without a hex boss to hold, and it is so tight that you have to hold the machine or boiler still, then other measures should be taken such as applying heat to the boiler and cold to the fitting. Sometimes heat is required to break a locking compound applied to threads during assembly.

i just put vinegar in the water reservoir and ran it, let it sit a bit, tilted it a bit and afterwards ran a bunch or water through. no smell and now it works fine. hopefully it will stay that way but with as hard as the water is around here it was silly to think it would not be required eventually.