Commercial Espresso Machines
Hey guys,
So I have a Rancilio Epoca that a friend of mine has inherited, however the pressure gauge is extremely temperamental. Sometimes the pressure will turn on and other times it will stay and only about 6 bars of pressure. Me being the wanna-be handy man took the case apart and started poking around inside and after I had gotten inside the machine I realized I have no clue what the hell to look for.
I did make some notes of outer physical problems and I was just wondering if any of you had some advice to look into. The first of which was it seemed that the pump was only triggering the pressure motor to turn on every once and awhile (resulting in the temperamental pressure). The other problem I saw was that it was one massive boiler that controlled two group heads, two steam wands and the hot water spout, and it looked extremely dirty and calcified.
It is about two years old and appears to be that it has never been cleaned, group heads included. We took it apart and scrubbed it down and got the outside and group heads and steam wands looking beautiful, but the pressure is still spotty. Would you recommend just looking to buy a new one? Or is it worth the effort to take apart the boiler and clean it and replace the motor attached to the pressure?
I appreciate any help you guys can give me!
--Aaron Jordan
Replies to This Discussion
-
Permalink Reply by Brady on
-
Hey Aaron. A couple of thoughts for you, from a guy that works on more Epocas than I'd care to count.
1. Wear gloves. Quite a few of those panels are way sharper than you might expect. Nearly cut my fingertip off with one about a year ago and still don't have 100% feeling there.
2. Always unplug it before poking around in there. Some machines will totally kill power when you turn the switch off - not these.
3. The motor pump should operate whenever a shot is being pulled or when the boiler autofill circuit engages. Intermittent operation is a problem. The first thing I'd do is check for voltage at the pump when the motor should be on but isn't. My suspicion is that you have an issue with the motor capacitor - if your multimeter has a capacitance check function, now's the time to use it. Check capacitance against the rating printed on the outside and replace it if it's more than 10% low.
4. Regarding your possible scale issue - it isn't uncommon for the outside of the boiler to look a little hellish. If you have a scale problem, I think you're probably out of the DIY realm. Is there a reason you suspect scale? Before removing the heating element or endcap you might try draining the boiler and inspecting the lower sightglass tube/port. The boiler drain is the strange long hexagonal fitting below the boiler just left of center - probably has a silicone tube attached to it. Put a pair of wrenches on it and loosen the stainless part a turn or so and you should see water drain out. Once it's empty, you can remove the lower sightglass tube and peek in to the tube and boiler port to assess the situation.
You may find this helpful. That page has links to online parts diagrams and manuals.
Good luck!
-
Permalink Reply by Mike Sabol on
-
I'd like to throw a few things onto the table to consider, as well, in addition to Brady's fine advice.
You are correct in seeing that there is only one boiler to power two group heads and two steam wands. This machine utilizes "heat exchanger" inside the boiler to heat the two groupheads. This functions very well to get the groupheads hot and keep the water for brewing espresso separate from the water used to create steam. There are a couple pathways for water in your machine and the water pressue guage will react to a number of situations. Those guages don't hold still for very long. When you mention that it reads 6bar at times and then jumps from there, that is normal. Many sites and buildings have between 4 and 6 bar of pressure in the plumbing system so your guage could simply be reading that, in which case it would be correct, and when the site pressure changes for some reason your guage will bounce around a bit too. The thing to look for is when pulling a shot you should see the guage jump up to around 9bar. And also, when the heat exchangers are first filled with cold water you could see the guage move up to around 12 or 13 bar at which point an expansion valve opens up and the guage will stabilize at some number. Brady can tell you exactly how that machines system operates.
So it's possible that you actually don't have a problem. Unless the pump does not turn on when you try and pull a shot or if the pump does not come on when the boiler calls for water. The heat exchangers don't call for water in the same way as they are fed via line pressure on a continuous basis. Does the unit pull shots correctly and steam correctly? If it does then it's normal for the pressure guage to jump around when you're not using the unit. Even if it's turned off it's still hooked up to the water in the wall and the pressure guage will read that.
Hope this helps.
-
Permalink Reply by Aaron Jordan on
-
Thanks so much for responding Brady and Mike!
Mike, I suspected scale purely because it looked a little hellish and I knew it had never been serviced. They wound up getting a technician to come in and look at it, replaced the pump and there was a leak in one of the lines that resulted in weak pressure as well.
So as of right now looks like everything is running tip top, thanks for the speedy response and education!
Barista Exchange Partners
Barista Exchange Friends
Keep Barista Exchange Free
Are you enjoying Barista Exchange? Is it helping you promote your business and helping you network in this great industry? Donate today to keep it free to all members. Supporters can join the "Supporters Group" with a donation. Thanks!
© 2024 Created by Matt Milletto.
Powered by
