Hi folks,

I have come into possession (on extended loan) of a MiniGrimac semi-auto. Unknown past, probably in need of some help, but in good cosmetic shape and doesn't look like it's led a hard life.

I don't want to kill it when I first power it up. It's an HX, presumably with boiler auto-fill (which of course might be gunked up with scale and non-functional), and no sight glass for manually figuring out how much water is in the boiler.

Any clues on how to proceed? Thanks.

-r

If I remember correctly you have a vertical boiler,
what I do not remember is how easy is to access the heating element at the bottom of it,
however
before powering up the unit
I will remove a wire from the HE or the pressurestat or the safety thermostat
so you will not take the risk of running the boiler empty and dry
check the the antivacuum valve "pin" is down (open) and open a steam valve,
then you can ether clean the water level probe BEFORE the initial filling or give it a try and see if it will fill up
keep an eye on the reservoir and see if the level is going down
if is plumbed in you could feel the water holding the hose moving

The heating element wires are kind of tricky, you need to remove the chrome bottom grate to access them.
The pressurestat route is probably the easiest way to go.

I recently did a complete rebuild on one of these that was in bad shape, but if you dial it in, you'll have a
nice machine

-Jim

JY if you have any documentation and/or pictures of your rebuild please share! I have one of these that I picked up for a song on Craigslist and I can't wait to go through it and upgrade from my Gaggia Classic. Not that I'm not getting decent shots out of the Classic, I'm just excited to have something better. I will need to re-wire at the minimum the ground circuit as the ground wire going to the top of the boiler is hanging on by one strand and the power cord that the previous owner replaced is orange which just will not do.

These are pictures I took for reference, because I just tore down the entire machine. Nothing too complicated though, this was my second rebuild, the first being a La Pavoni P/Tre 2 group.
I ended up replacing all the soft parts(gaskets, o-rings), and a few other things like the safety valve, and pressure gauge.
The only other thing I have are the user's and parts manual I posted above. Also, Marcantonio at Royal Falcon Group was very helpful. I believe he can get anything you might need for this machine.

Turned out to be a nice daily driver.

-Jim

For what is worth, here is my experience with the restoration of a Minigrimac (1998 vintage, direct-connected to the water main, programmable dosage).

Here is a list of parts I had to replace:

heating element
Gicar electronic control module
autofill level probe
pressure stat
pressure release valves
water intake controller microswitch
solenoid coils for hot water and pump

I also cleaned and decalcified each and every pipe, plus the boiler itself.

Now, the machine reaches 1.5 bar pressure in 6 minutes(!). Another 6 (total 12) and I can pull a 'God-shot'.

I've had other HX machines before, nothing comes even close.

palika,

Are you sure you're running it up to 1.5 bar? I'm pretty sure the max pressure noted on the service tag is 1.3.

I'm running mine at 1.1, and getting right around 200F +- at the grouphead.