Izzo Alex HX - Pump Runs Constantly

Equipment doesn't work? Troubleshooting? If you're handy, members can help.
Enz0man

#1: Post by Enz0man »

Hello everyone, I'm hoping you can help me because I'm almost at my wits end with my espresso machine. Some backstory, I bought a used Izzo Alex HX machine that was built in 2010 from the original owner. It needed some work which I knew when I bought it, and after I got it working it was fine for a while.

One day this issue started while the machine was on, where the pump just randomly turned on and didn't turn off until I shut the power switch off. It's like it was trying to fill the boiler but it couldn't. And when I turn the machine off and right back on, the pump turns back on a few seconds after flicking the power switch. Only if I let the machine fully cool down will it work properly again. I used it for a bit in this state because it would only happen if I left it on for more than a couple hours at a time. Then it slowly started happening more frequently, and after a shorter amount of time. Then a few months ago, it became unusable. The pump would turn on as soon as I turned the machine on, even if it was fully cooled down. And anytime the pump was on constantly, the pressure was at 9 bars. At this point I tried searching for a solution but ultimately never found anything and let the machine sit.

Fast forward to now when I got myself a new-to-me grinder (Vario) and I really want to get some good espresso flowing again. The similar issues I found on the forum seemed to point to either the fill solenoid being stuck closed or the water level probe not sensing water in the boiler. When the pump runs I can open the group head lever and water will flow until the tank runs out of water, so I feel like the solenoid itself is fine unless there's a way the water can bypass the boiler and go straight through the grouphead somehow? I also took apart the fill solenoid and made sure the valve moves freely, and even turned the machine on without the valve installed to make sure water flows, which it does.

Next was the water level probe and this is where I thought I was getting somewhere. It wasn't covered in scale or anything, but when I took the probe out and grounded it against the chassis of the machine, the pump would stop. I can basically control the pump by grounding the probe against the body of the machine. So I ordered a new level probe and installed it, only to have it do the exact same thing. Doesn't sense anything in the boiler, but if I ground it the pump will shut off, and water still flows if I open the grouphead lever.

Another behaviour that I am not sure is normal is while the pump is on, the PID display is off. But when I flip open the grouphead lever and let water flow through, the PID display turns on. So while the pump is running, the PID display doesn't turn on unless the switch behind the lever is pressed in. It's done this since day 1 of me having the machine, even before the pump problem, so I assume this is normal?

I am starting to think this may be a wiring problem, or a problem with the Gicar unit that the level probe plugs into. The machine has seen some use and everything on the inside seems to have been affected by the heat to some degree, so I wouldn't be surprised. Even though the pump runs at 9 bars I don't think it's a blockage? But I could be wrong. Any advice or troubleshooting steps would be greatly appreciated because I don't know what else to do at this point.

JRising
Team HB

#2: Post by JRising »

But the boiler doesn't over-fill and water doesn't spray out from the safety valve?
Something is stopping the boiler from filling. The likely cause is a blocked boiler-inlet solenoid valve. If the boiler were actually filling while the pump was running, the safety valve would have been blowing off water.
Since the boiler-fill circuit does seem to work (stops when grounded) the pump will probably stop when the boiler is full enough to reach the probe.

Enz0man (original poster)

#3: Post by Enz0man (original poster) » replying to JRising »

Correct, the boiler does not over-fill and no water exits the safety valve. This makes sense, I'll take off the pipe that leads into the boiler and see if there's a blockage.

But while the pump is running if I turn on the grouphead, water flows out fine and will continue to flow until the water tank is empty. Is this bypassing the boiler somehow?

User avatar
cafeIKE
Supporter ❤

#4: Post by cafeIKE »

Can you hear the 2-way valve 'clack' when you ground the water fill wire?
If not, the solenoid is stuck or the coil is open. You can check the coil with an ohmmeter.

Enz0man (original poster)

#5: Post by Enz0man (original poster) »

Update: found the issue for sure this time. After taking solenoid valve out and the pipe that leads to the boiler and confirming nothing is blocked on that end, I moved to the solenoid coil. I reinstalled the solenoid valve and coil, left the pipe leading to the boiler off, put a rubber hose on the end of the valve to run the water into a bucket, and turned on the machine: no water.

Pulled the coil off and stuck a screwdriver on the inside to see if it would magnetize when the machine is turned on. Again, nothing.

Voilà, dead coil.

Now I suspected this originally and tried to find a replacement coil, which I was unsuccessful in finding. Here is a picture of the coil on the machine, I assume it has to have these exact specs to be able to work:



Googling sirai coils previously only lead me to either 220v ones or ones with various other different specs. Any insight here? Or just contact service/repair places until I find one.

Thanks again!

Enz0man (original poster)

#6: Post by Enz0man (original poster) »



Other side of the coil

User avatar
cafeIKE
Supporter ❤

#7: Post by cafeIKE »

sirai ZB10a 110v
will get you what you need

Enz0man (original poster)

#8: Post by Enz0man (original poster) » replying to cafeIKE »

Tried searching for one but can't seem to find the exact same one. They're either different voltage, or different model number, etc. Even thought I found one from a UK company but they don't ship to Canada :(

Anyways I'm sure I'll find one eventually, I have emailed a few espresso repair/parts supply places already. Thanks everyone for the help!

Enz0man (original poster)

#9: Post by Enz0man (original poster) »

Ended up finding one that I am fairly certain will fit. The dimensions are exactly the same and it has the same size opening for the valve. Also same voltage and pretty much the same wattage.

https://www.espressoparts.com/products/ ... 6548174011

Espresso Parts is out of stock but a more local shop to me, coffeeaddicts.ca, is able to special order Parker coils so they have it on the way for me. Will update here again when I receive it to see if it fits!

Enz0man (original poster)

#10: Post by Enz0man (original poster) »

Update, the coil I posted above arrived and it fits! Machine works now, thanks for the help everyone.

On a side note, when the machine idles for more than a few minutes, when I lift the lever the pump turns on but it takes 3-4 seconds for water to flow and pressure to build. Is this normal? Currently running from the water tank, not plumbed in.