Anyone fixed an espresso machine?

[The Natural Philosopher]

Ours got buggered 18 months ago, and needed a new gasket which I got...but in the meantime something seems to have gone wrong elsewhere.. and I am a bit stumped.

What it consists of is a reservoir of water that goes to a pump, which pumps at what must be pretty high pressure into a boiler thingie. The boiler output goes to a steam valve that goes either to the coffee head itself which has a pressure switch - seems to need about 2 bar or more to let steam out - or the steamer pipe for frothing the milk.

The basic trouble is that nothing is coming out at all. I did get some steam briefly.

I have checked all the easy to get at stuff - the valves and pipes from the boiler to the valve etc..

The pump runs - well makes its buzzy noise - but seems to draw no water from the reservoir, but that pipe is OK as I disconnected it and sucked water up.

My guess is that something is scaled up in the pump or boiler area, but without more than a trickle of flow..how to descale it?

What I also don't understand is why the pump seems to be configured to run ONLY when making coffee - not when steaming or topping up with hot water etc..is it that the high pressure an flow can only be provided by a pump. whilst hot water and steam can be gravity fed?

Normally I wouldn't bother, but its the wife's BIRTHDAY...;-)

[The Natural Philosopher]

Oh., I sussed it.

The pump IS a high pressure one and needs priming. You do that by filling it up with water to the FULL mark, not where SWMBO had filled it to ;-)

Thanks to all who failed to reply in time..anyway SHE is happy. Phew.

[Andy Hall]

Yes I have. A Krups one. Works well. Actually I think they all work in much the same way.

Normally you should descale regularly so that this doesn't happen

At this point, I think you will have to disassemble and get some descaler into the pump and pressure chamber in some other way.

The principle of operation is simple enough. There are sprung valves on the input and output and the pump is a vibrating plunger. It's similar to an aquarium air pump but obviously beefy.

Another thing that can have happened is that one of the valves has failed or there is some crud under it. That will involve disassembly as well. Take care because there are probably pingfuckits inside.

What happens is that some water is kept around and boiled and opening the steam jet valve causes it to be forced through the jet. There is normally enough water to heat the amount of milk needed for a few cups of coffee. You will find that if you run the jet for longer it will probably run out. Some of the larger Gaggia machines have a separate pump arrangement for the steam generator.

Ah, so it could even be a trip to Newmarket to do business with your favourite Currys shop ;-)

[Andy Hall]

Enjoy the rest of your day :-)

[Steve Firth]

Does it have a steam jet? The instructions usually say that after the machine has run dry you will have to prime it by opening the steam jet and allowing the machine to pump until water runs out.

[Huge]

I discovered to my horror last year that Krups are a French company.

[Andy Hall]

Yes I know. The product looks distinctly teutonic though.....

[Mathew Newton]

Thanks for that.. Any tips on removing coffee from the now-drenched keyboard?

[Steve Firth]

Not much difference, they all collaborated during the war anyway. So you can be confident that it's the same thing, all things considered.

[Huge]

Yes, but the words "French" and "engineering" don't commonly go together - see "Saniflo".

[The Natural Philosopher]

Yup. The bloody steam pipe clogged and I stripped it all down AGAIN to find it was the bit on the outside..

Still..got a nice cappucino in front of me now. Yum. Slurp

[The Natural Philosopher]

Or TGV? No, the frogs CAN do excellent engineering.

[Andy Hall]

One trick is to blow some steam into plain water before closing the machine down.

Excellent.

[Guy King]

The message from The Natural Philosopher contains these words:

We have to descale ours fortnightly or it all grinds to a halt.

[Guy King]

The message from The Natural Philosopher contains these words:

Their nuclear power stations seem to be quite good, too.

[Pete C]

That's because the french taxpayer foots le bill.

cheers, Pete.

[Andy Hall]

That's OK. Can be set against their CAP subsidies.

[Guy King]

The message from Andy Hall contains these words:

Common Atomic Policy?

[Andy Hall]

Now there's an idea. Build all the new nuclear plants in Scotland with EU subsidy.

[Owain]

Would you really want a nuclear plant that cost 10x the budget, came in several years late, and still had bits falling off?

Owain