Problems with CS2

[prompt38]

Hi all,

I was recommended to make an inquiry on this forum about the CS2 from Starbucks.

We've been called in to service this machine in a remote mountain location... with barely any training on it so I'm hoping to get some help.

The machine powers on and seems to function okay except that the external pump will not work.

When the machine is powered on and prompted to do the rinse cycle, the solenoid engages and lets water flow from the spout. However the pump does not cycle on. When testing the pump using the output test, it also does nothing.

I have removed the plug from the pump to check the voltage and I'm getting about 40V between the two hot lines.

Seems like it might be an electrical/wire issue... but nobody has messed with the wiring and I don't see any loose or cut wires.

Any ideas?

 

[Cafeparts]

The Mastrena/CS2 have a fuse for the pump motor on the power board, I believe it is the large HRC fuse. Have you checked the fuse?

Also if the fuse is bad, you might have a bad motor or a bad motor capacitor, check the capacitor value with an multimeter. It should be withing +/- 10%

Rudy
Cafeparts.com

 

[CCafe]

The big fuse is for the grinder the circuit, the two little ones are for the 10 and 20VAC circuits. I would venture to say the triac is shot on the Power Distribution Board. When you start getting stupid voltages across the both legs on a circuit with a triac it tends to be the triac has fried. If the circuit has a fuse and it was blown you wouldn't get a voltage at all as there is no way to complete the path for 1 leg to the other.

I'd pull the power drawer and look for something that has burnt up. Either way make sure your repair tech comes out with a new Power Distribution Board or a whole new power drawer.

You can also test each leg to ground to see what you get for voltage on L1 and L2. I would venture to say your meter is going to show you something goofy for one leg or the other or even possibly both. I had Bunn brewer that fired up and kind of heated the water but just didn't work for a hoot. Upon further inspection L1 was providing 120V which incidentally also powers the the brewers 120V electronics yet, L2 was providing about 40V. In the end the breaker had actually tripped but it was bad and failed to cut the circuit completely.

 

[prompt38]

Thank you both for your advice. I checked the fuses on the power drawer and all 3 are good. Just to confirm, we had the power drawer swapped in from another machine and it didn't change anything.

I measured the voltage on the pump plug and it's showing 92v on one leg and 32 volts on the other. Very odd.

Do either of you know how to remove the top control panel and back panel? I'd like to check the wires at the back but can't seem to get the top or back panels off.

Thanks again!

 

[prompt38]

Oh yea, also swapped the pump assembly thinking maybe it's the capacitor but that didn't help either.

 

[kohana]

Hello CCafe,

By chance do you know where I can get my hands on a Mastrena CS2 espresso machine manual?