Izzo Alex Duetto no heat or pressure

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

#1: Post by EdSilk »

I have an Alex Duetto, no heat and no pressure in either boiler. Heat and pressure were fine with no problems, everything was working before I rebuilt the group head. After that rebuild, no heat, no pressure. The motor activates and delivers water to the head when activated by the lever. I checked the reset buttons on both boilers, they are not popped. I checked for scale in the solenoid, found none, and have (cold) water flow there. I don't believe that either boiler is filling. I may be wrong on that. In the rebuild, I replaced the group drain valve, pre-infusion valve and brew lever valve and various gaskets and o-rings. I checked my work on the mushroom and it appears to be correct. Checked vacuum breaker, clean. Checked PID, all correct settings. In checking the machine before the rebuild, I laid it on its side. Not sure if that was ok. The water supply is mains, and the lever is in the input supply lever is in the correct position and the gauge does read the mains pressure. If I switch to reservoir mode, and flip the brew lever up, the pump draws from the reservoir. But does not run to fill the boilers as might be expected. When I turn the power switch on, there is a "click" after about 1/2 second, coming from the Micro ST enclosure. Any suggestions appreciated.

richiekess
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#2: Post by richiekess »

I would check the wires going to the PID...

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BaristaBoy E61

#3: Post by BaristaBoy E61 »

What happens when you turn the power 'OFF' to the steam boiler and just leave the main power switch 'ON'?
"You didn't buy an Espresso Machine - You bought a Chemistry Set!"

EdSilk (original poster)

#4: Post by EdSilk (original poster) »

Thanks. No difference with steam boiler switch on or off.

EdSilk (original poster)

#5: Post by EdSilk (original poster) »

Richikess, thanks. What type of PID wire check do you recommend. Wires are in place and not charred. PID display is working. I earlier reset to default during troubleshooting. I have a multimeter. Any advice appreciated.

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BaristaBoy E61

#6: Post by BaristaBoy E61 »

If you're direct plumbed, the brew boiler should be filling by virtue of the line pressure. I think the next stage would be to verify wiring and after that verify electrical function of the solenoid and relays or SSR if your series has that - but only if you're competent to do that!

Seek professional servicing if you are in doubt of your knowledge and trouble shooting abilities!
"You didn't buy an Espresso Machine - You bought a Chemistry Set!"

EdSilk (original poster)

#7: Post by EdSilk (original poster) »

Baristaboy, thanks.

I will test the operation of the solenoid.

You suggested wire verification. If all was working before I rebuilt the group head, and if no wiring was disconnected or changed, and if I've confirmed that there are no charred or disconnected wires or connectors, can you make a suggestion for further wire verification.

I have not tested continuity or resistance at heater elements, but both were working before I rebuilt the head, which should not affect the boilers.

It occurred to me that I have not checked the expansion valve. Could that be a culprit?

Thanks
Jeff

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BaristaBoy E61

#8: Post by BaristaBoy E61 »

Do you own and are familiar with the use of a digital multimeter?
If so, you can test the continuity of the solenoid valve first. The attached pic is what you should see, about 683 Ohms, ~0-Ohms would mean it's shorted and an Infinity symbol would mean that it's 'Opened' as in no continuity.

You can check the continuity of the heating elements as well by just pulling off at least 1-connector from each element.

You can start with all this.

Attached is also a pick of the brew boiler heating element and what you should see on a meter.

I don't think it's the expansion valve, as there is not heat and no opportunity to malfunction as there is no electrical component to its operation.

Make sure the machine is unplugged!




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richiekess
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#9: Post by richiekess »

There's nothing in the rebuilding of the group head that would cause this. I keep wondering about your laying the Alex on its side and whether a wire came loose from a terminal. I would look over every single connection.

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BaristaBoy E61

#10: Post by BaristaBoy E61 »

richiekess wrote:There's nothing in the rebuilding of the group that would cause this. I keep wondering about your laying the Alex on its side and whether a wire came loose from a terminal. I would look over every single connection.
I agree, there's nothing about rebuilding the group head that would cause this. There's also nothing about laying it on its side or back that should cause this either but every physical electrical connection should be verified as that's the easiest place to begin. Failing that, electronic trouble shooting would be the only way to prove what's wrong and then correct it.
"You didn't buy an Espresso Machine - You bought a Chemistry Set!"