This will be my first post on this forum, although I wouldn't say I'm new to it. I read a lot of very useful information before purchasing my second-hand and now refurbished Junior.

I'm struggling with the dosing chamber of my plumbed in machine. First of all, I find that I cannot manually stop a shot by pushing the shot button a second time. Is there a trick to do so? This would come in very handy with flushing the group and especially with backflushing (as no water gets past the blind filter and the opv is feeding excess water back to the reservoir the shot would continue endlessly). Also how would you prevent the opv from introducing detergent contaminated water into the dosing chamber.

Secondly, I find that with the setting of shot volumes, there is a large difference between the blank shot volume and the volume using actual coffee. Does the puck absorb that much water or is the opv hose to the dosing chamber filling up? Maybe I'll find out the answer to this question myself after further experiments, but would like to hear your thoughts on the matter.

Thirdly, during a blank shot (no coffee in the piston) I find that the flow of water is sometimes briefly interrupted during the shot. Is that a result of using a vibe pump? Should I worry?

Thanks for your thoughts, especially Ken Fox (as I suspect you will bite on the junior name tag of this post )

First, welcome to HB.

I'm not at all familiar with the older plumbed in versions of the Jr., which had a vibe pump. The ones I've seen don't have any buttons to push, rather they have knobs that turn. Are you sure that you have a vibe pump machine and not a refurbished (current model) rotary machine?

The OPV does not recycle "used" water, e.g. water that has already come in contact with detergent or coffee. It bypasses excess water on the input side.

I don't know how your machine is hooked up. With a plumbed in machine I would think that the OPV bypass water would go into the drip tray and out the drain, not back to be recycled for later use in espresso shots. Before I completely plumbed in my old vibe pourover, I did "recycle" the OPV discharged water back into the pourover tank, but I now have it discharge into the drip tray since I've resolved all the old issues I used to have with poor drip tray drainage, after my kitchen was remodeled.

Shot volumes are set "electronically" on the rotary Jr, with the touchpad. The vibe plumbed in machines used "rods" to adjust the shot volume, and I think you had several specific choices but not a continuous range, as with the rotary machine. I've never seen a vibe plumbed in machine adjusted for shot volumes, just seen pictures and discussions (by other owners, not me) on the internet, in the distant past. Since you bought your machine refurbished, I'd assume that you have someone to go back to for help (i.e. the person or store you bought the machine from) and I'd suggest that.

The puck absorbs a lot of water when shots are made. There is also a change in the flow rate based upon the resistance to flow that the machine experiences. If the machine is simply "dispensing" water through the head, either into an empty Portafilter or directly into the drip tray or another vessel, it will flow very rapidly. If there is resistance, such as from a coffee cake in the PF, the flow rate is much slower. I'm sure I'm not understanding your question, so this is probably why my explanation is also incomprehensible

ken

Thank you Ken for your reply.

The button I'm referring to is just the start button in between the two rotary switches (left on/off and right shot volume selection). So indeed I have the version with the plastic dosing chamber and the rods. I do understand how to set the volumes, the question is more related to stopping the shot before the selected volume is reached, as in the case of backflushing with a blind filter is needed. Maybe somebody with the same machine can help.

As for the refurbishing, did that myself. With success.

PIM, just send you a PM. I am a new owner of the machine you describe. To stop the flow turn the right hand knob to a different position.

Pim wrote:Thank you Ken for your reply.

The button I'm referring to is just the start button in between the two rotary switches (left on/off and right shot volume selection). So indeed I have the version with the plastic dosing chamber and the rods. I do understand how to set the volumes, the question is more related to stopping the shot before the selected volume is reached, as in the case of backflushing with a blind filter is needed. Maybe somebody with the same machine can help.

As for the refurbishing, did that myself. With success.

Are you possibly referring to the round button which fills the boiler? If your machine has a sight glass, that button turns on the pump and opens up the valve in the input solenoid that directs the water INTO THE BOILER. This is for manually filling the boiler, in a machine that does not have autofill.

ken

It doesn't matter if your flow regulator is electronic or prehistoric, unless it is also psychic, you need to program it while making an actual shot of espresso. If that shot is unsuccessful, i.e it flows too fast or too slow, start over. The water absorbed by the puck, the amount of crema versus liquid, and the amount of water over the puck all vary according the success of the shot.

I am referring to that button but as my machine has autofill this button has the function of starting the shot. The suggestion of bgn, turning the right-hand knob turns out to work.

Thanks for your replies.

Of course I have not seen your machine and I have no personal experience with older, vibe pump driven, plumbed in Juniors.

I am however unaware of the existence of any plumbed-in Cimbali Junior with a vibe pump and boiler autofill. The current vibe pump powered model is a pourover and DOES have boiler autofill, however it lacks a sight glass. If you have such a machine (plumbed in, vibe pump drive, with sight glass and autofill) then this shows the limit of my knowledge on this subject. If your machine has a sight glass, I really doubt that this button does what you think it does; I can't see a reason why Cimbali would have made a machine with a sight glass AND boiler autofill.

It is also possible that you are misinterpreting the function of this button, and that it does in fact fill the boiler but does not initiate shots, at least if the internal plumbing is put together in the way that it was designed to be used. You stated that you did your own "refurbishing." Is it possible that something got hooked up incorrectly? I have myself installed the input solenoid of my old vibe Junior incorrectly, mixing up the in and out ports, so I know that this is possible to do.

ken

Hi Ken,

http://www.horeca-parts.nl/Koffiemachin ... unior.html

This is a link to the schematics of the junior. As you can see there is a water tank version (bottom one) and a plumbed version (The one above the previous). Mine is precisely like the latter. VD106 is the lucifer two way solenoid controlling the boiler fill. The boiler fill level is measured by a sensor in the top of the boiler (not shown in the picture).
CD716 is the button we're discussing. If I push it the shot starts, it continues untill the water level in the dosing chamber (CD697) reaches the end of one of the selected rods (depending the position of shot volume selector (CD718). The shot stops and the dosing chamber refills.

If I tap water through the hot water tap the boiler refills automatically.

Kind regards,

Pim

Hi, Pim. It looks like I have the same machine you do. I have attached a picture of the control face.

I bought the machine several years ago off ebay. I had it professionally reconditioned, and they said it made a great cup of coffee. However, because of circumstances, I never installed or used it until today. I have several questions, and would appreciate any help offered:

I have plumbed it in, it fills automatically, no problem. But I think the pressure regulator located above the sight tube is bad. There is a constant hiss of steam escaping. Sometimes the pressure is able to get up to 0.8 bar and the element turns off, other times no pressure can be built up it is all escaping. Should that pressure valve always be open, maybe to warm the cup tray? Is it adjustable? Can it be cleaned, or should it be replaced?

What is the function of the orange light next to the cup with a line drawn through it? It seems to be intermittent, possibly due to the pressure problem. Does the light on mean the machine is ready?

Thanks for the info

John