Hi all

Been the longest time since I was here had to re-register...glad to see all well

Need a bit of help my T1 grouphead is running 'cool' for some reason - rather than the usual volcanic hissing and cooling flush required after a period at idle I'm having to run water through the group to heat it up - and even then can't get to hiss stage mostly. P-stat setting hasn't changed sitting happily at 1.1 or so, tweaked it up a bit but it hasn't helped. Plenty of normal steam/hot water.

I'm guessing something is up in the heat exchanger process but can't quite decide where to start - any ideas? I'm 9 months or so the other side of a 10 yearly full strip down descale and refurb where pretty much everything got cleaned or replaced so no fear of pulling her to bits (has worked perfectly since), but just wondered if anyone had thoughts on where to start or what the issue might be before I start pulling fittings off

Cheers
Matt

Shut it down, turn off the water and remove the group bolt atop the grouphead and look in there for scale and/or debris. Also check the wire filter screen around the group jet. It sounds like your heat exchanger is either full of scale, or you have something blocking the thermosyphon path to the group. I just did a big tear down and replaced all the gaskets, descaled, replaced the wire group filter, reamed out the water path channels, put a delay on make relay on the pump and a group head PID for real time temperatures in the water path on my 10 year old A3. I also replaced the pressurestat which tightened up my deadband quite a bit. I will do a how to article at some point in time.

Thanks Dave. I am 100% sure the HX is not full of scale a couple of days in a bucket of citric solution a few short months ago sorted that out Sounds like your tear down was as extensive as mine. Water here is soft soft 30mg/L range so scaling is a very long term issue.

The siphon jet under the Inox filter is a good shout though that is a pretty small hole maybe some tiny particle in there. Does water only go through there when the pump is on though forcing it down through the showerscreen? Is there water circulation round the rest of the group at idle or only when the pump is running? I'm suspecting something in the thermosyphon but those are pretty big pipes relatively speaking. Hmmmm...will pop the group cap off and have a look.

That little group jet only supplies water to the group when you hit the brew. The group head should be idling at around 208F at your pressure stat setting. I run my machine just a little cooler.


The flash boil water coming out the group is the superheated water in the heat exchanger. If the group is idling very low due to a restriction in the thermosyphon it could/would absorb some of that energy but you should still get some hissing and sputtering. None at all means your heat exchanger is running cold which would be indicative of scale. I suggested taking the cap off the group to see if you have a chunk that may have dislodged and has partially plugged the loop. The other option is a leak in the loop and the water is boiling off. That would present itself by having a long delay in the water out the group when you activate the brew. The group head would be void of water and it would take a couple seconds for the pump to fill the air space before it started out the group. The 60 series machines come to full pressure in about 1 second so the water flow should be instant.

Freshly descaled it should look like this....

I am assuming you have it plumbed in. Another trick you could try, just crack the group bolt. If you have an air lock (trapped air in the group) the mains pressure would push the air out and water will leak around the bolt. Then tighten it back down. I usually bleed out the group like that after I have disconnected it from the mains and drained it. The other obvious option is not long enough of a pre heat. These big beasts take a good hour to heat from cold. I leave my machine on 24/7.

Hi all

Posted about this some years back, can't reply to the thread now but wanted to post the fix in case anyone comes across the same issue.

Elektra T1 has lost her hiss

Rather than scale the culprit turned out to be the check valve where the water enters the HX system.


There was deterioration in the o-ring inside the sleeve of the valve that is supposed to stay shut with a spring and ballbearing check until the pump activates to feed the HX. This was resulting in a constant tiny entry of cold water, and backflow of hot water from the HX circuit, cooling things slightly and meaning the HX never got to flash boil as normal. The valve is serviceable with an o-ring the same size as the small Viton solenoid ones.

Elektra back to volcanic hiss. Hope helpful for reference.

Matt

So now I am stuck again.

Thought this was sorted had a few days of flash boil hiss after looking at that check valve, and now we are back to cool again - max water temp out the head is about 196 and never any flash boil.

Have replaced the check valve with a brand new one and it turns out even the new one the spring and ball bearing does not stay closed against the mains pressure (2 bar) so I am at a loss as to what it does in the circuit?



Cracked the top off the HX and apart from a tiny bit of powdery scale right at the bottom which I have cleaned out it's pretty clean.

Boiler idling between 1 and 1.1 bar nice and tight - lots of steam and hot water. Water out the head is pretty instant on pump activation so it's not an air lock.

Would really appreciate any ideas how to troubleshoot the HX loop some more

Matt

Still stuck with this.

Installed a fine gauge TC into the grouphead by the brass dispersion disc. After a long idle this can deliver the first lot of water at as low as 170F. No super heated water, no hiss. Series of 30ml flushes 1min apart gets the temp up a bit but never over 200F. Tweaked stat up to 1.2 and have steam pressure to burn.

Shortly after my last tear down and descale only a few months ago (when I thought it was the check valve) I had some hiss I think, and now none again. Something is definitely wrong with my HX and I am at a complete loss. It is winter and mains inlet water is cold (10c) - could that possibly be it

EDIT: thinking hard about how the heat actually transfers to the HX have raised the auto fill probe between quarter and half of an inch to get more HX submerged in the boiler water. Now getting water about 205 at my bell TC. So that appears to be a partial solution not sure if it's the whole answer