[T](https://www.coffeeforums.co.uk/account/ "Account details") * [Home](https://www.coffeeforums.co.uk/) * [Forums](https://www.coffeeforums.co.uk/forums/) * [Coffee Forums](https://www.coffeeforums.co.uk/forums/#coffee-forums.3) * **[Technical | Faults | How-to's](https://www.coffeeforums.co.uk/forums/technical-faults-how-tos.20/)** # Elektra T1 Heat exchanger Espresso Machine Cool espresso [Tags](https://www.coffeeforums.co.uk/threads/elektra-t1-heat-exchanger-espresso-machine-cool-espresso.65862/tags)[crema](https://www.coffeeforums.co.uk/tags/crema/) [elektra](https://www.coffeeforums.co.uk/tags/elektra/) [heat exchanger](https://www.coffeeforums.co.uk/tags/heat-exchanger/) **[Jump to Latest](https://www.coffeeforums.co.uk/threads/elektra-t1-heat-exchanger-espresso-machine-cool-espresso.65862/post-878192)[Unfollow](https://www.coffeeforums.co.uk/threads/elektra-t1-heat-exchanger-espresso-machine-cool-espresso.65862/watch)** **1 - 4 of 4 Posts** [T](https://www.coffeeforums.co.uk/members/twotone.8889/) #### **[twotone](https://www.coffeeforums.co.uk/members/twotone.8889/)** ##### **Registered** Joined Jan 13, 2015 509 Posts **Discussion Starter** · [#1 ](https://www.coffeeforums.co.uk/threads/elektra-t1-heat-exchanger-espresso-machine-cool-espresso.65862/post-878167)· [Apr 14, 2022 (Edited)](https://www.coffeeforums.co.uk/threads/elektra-t1-heat-exchanger-espresso-machine-cool-espresso.65862/post-878167) Hi, just wondering if anyone can offer some advice. I have a 2007 Elektra T1 Deliziosa and I'm really struggle to get decent espresso. I buy beans fresh, on subscription, from Coffee Compass, and no matter the beans I rarely get crema however I know that the lack of crema is not an indication of the beans not being fresh and the size of the cup can make the crema almost non-existent but I'm not getting any crema regardless of the beans and regardless of where I buy them from, in the recent past I've bought from Rave and Redber and a few other roasters who advertise on here. I have a La Cimbali commercial grinder with, I think, 73mm burrs and it grinds perfectly okay. I grind 14g and pull 28/30g of espresso in around 35 seconds and I have also adjusted the grind to go long and short but no difference. I mainly drink milk based coffees so as a result I didn't really notice this issue too much but I've been tasting the espresso recently and to my mind it's not very hot and I'm wondering if this is the reason that I'm not really getting decent crema? The machine seems to be functioning properly, the hot water dispenses at around 95degrees C in a cup and there's plenty of steam but the coffee in the cup is only around 70 degrees C and it comes out the brew head at about 77 degrees C. I regularly clean the shower screen or replace it and I clean the brass shower screen holder (for wants of a better description) and I clean out the eight or so holes in that I do this at least once a month or sooner. I also flush the machine before making an espresso to cool down the heat exchanger so that the coffee doesn't burn but and the machine is on for sometimes an hour before making a coffee and sometimes it's about ten/15 minutes. Thanks for any replies. Tony I started a thread on the old forum here guys might save me re-posting photos etc. https://www.coffeeforums.co.uk/threads/elektra-t1-heat-exchanger-espresso-machine-cool-espresso.65862/#post-878175

A bit of an update. I removed and cleaned shower screen and brass dispersion thing with the ten holes and gave both a good clean I also removed the top nut on the group head to clean out anything in there, the nut has a spring and a shaft type thing that fits over a bolt which I think is the solenoid below the group head so I'm presuming when you push the button for a shot of coffee then the solenoid pushes the spring up to allow water go through the group head but either I've not re-installed the assembly properly or I've managed to block something up either way I'm not getting water out of the group head now😞

It sounds like the machine is scaled up, what sort of water are you using? from the pressure guage the pressure looks normal at around 1.2 to 1.3 bar. This sort of machine needs at least 30m to warm the group/p[ortafilter up before it's ready to make coffee. > @"Twotone2"#p15383 the nut has a spring and a shaft type thing that fits over a bolt which I think is the solenoid below the group head so I’m presuming when you push the button for a shot of coffee then the solenoid pushes the spring up to allow water go through the group head but either I’ve not re-installed the assembly properly or I’ve managed to block something up Do you have a photo/s of this part

Hi @"DavecUK"#p15408 Thanks the part is no 6 in the PDF drawing below it's an injector much like a pilot injector on a boiler. I sorted the machine by cleaning out the hole in the injector which is tiny 0.9mm I think, the temperature differential is now about 1°C. I might dial back the pressure stat to what it was before I adjusted it yesterday, the steam and hot water temperature are a good bit hotter than before, might be a good thing though? I replied in a bit more depth to a poster in the old forum who has been suggesting a few things. Here's the link including photos which I updated earlier on this morning. Thanks again. Tony https://www.coffeeforums.co.uk/threads/elektra-t1-heat-exchanger-espresso-machine-cool-espresso.65862/#post-878233 https://www.home-barista.com/downloads/Elektra_Sixties_1gr_Parts.pdf

Hi @"Twotone2"#p15479 Tony I have this machine. Its almost certainly scale in the HX, when mine starts to run cool brew temps that's always what it is. I have a very fine thermocouple jammed in the group bell so keep a close eye on it. 2 options - crack the top cap on the head as you have and remove spring arrangement/gliceur jet etc and descale in separate bowl. You also then need to remove the front cover above the drip tray and undo the left hand pipe to drain the HX from its lowest point (messy, have shallow tray to catch water - remember to turn water off before you start all this if plumbed in 😀 ). Put pipe back on, then refill HX from top group cap with descale solution, I use food grade citric at 30g/L. Leave an hour, drain out via bottom pipe again, and repeat. Option 2, open HX from on top of boiler. Often requires gorilla socket skills and a new gasket so maybe try other way first. Hope that helps - shout if you need pics/more help Matt

Hi guys, I'm still struggling with this machine, the espresso is a bit shit to be honest and I'm at a bit of a loss now I've ordered a naked PF with a 21g basket which should arrive tomorrow cause I think I might be having issues with channeling but despite buying fresh coffee beans from various different places I don't get any crema, ever and the coffee isn't great as I said in my OP because I drink mainly milk based drinks I don't really notice it much but in an Americano or an espresso the coffee would be sent back if I was buying it in a cafe. Basically I'm not managing to pull decent shots within a 25/30 second pull despite the grind then I either get long times ie around 60 seconds from when the coffee comes out of the spout until I get about 28 g in the cup (I'm using the stock 14 g double basket) so if I go coarse the coffee stream starts blonding almost immediately and if I go fine it takes ages and drip drip drips out of the spout no steady stream, no honey like constancy just basically poor coffee. Last week I replaced the solenoid valve (part number 18) after having a word with the guys at espresso services in Govan they also gave me some Jaguar phosphoric acid descaler which I used to descale the top part of the group head by removing the hex nut (part no 1) and pouring some descaler in and leaving it for about an hour then flushing. The problems have gotten less with the new solenoid valve (a bit of an improvement) but it's still not right the guys at ES thought that the issues might be 1) SV 2) pump head 3) scaled up HEX but I checked the pump with a blank disc in the PF and I'm getting 8/9 bar on the left hand gauge but I know that the gauge could be faulty but it does seem to be working fine ie 2.5 bar without the pump engaged and 9 bar with it engaged. The boiler pressure up to temp reads about 1.3bar as I previously adjusted the pressure stat which did make the coffee in the cup hotter and I videoed & timed the water coming through the group head at about 60 seconds/90g and temp of the water from the group head is around 94/5 degrees C. So obviously I'm going to take the machine into ES for a proper service and have them look at it properly as there's only so much advice they can offer from my descriptions of what's going on but I want to try to eliminate a few things first or at least be able to provide more information so I've gone back to basics ie fresh beans freshly ground, tamping, distribution and hot cup and flushing the machine which is why I've ordered the naked PF but I don't think it's operator error it may be that I'm not flushing the machine properly but I've started flushing it for around 25 seconds before a shot and again no difference to the coffee from before when I was maybe only flushing it for about five or six seconds. The only other variable is the grinder which is a La Cimbali Magnum grinder with 73 mm burrs which I bought second hand from a member on here about four years ago the burrs were brand new as I recall when I got the machine and I grind about a half a kg of beans a week but I've no idea if the grinder is faulty certainly the grinds look okay to me but who knows and I don't have another grinder to try however my son has a cheap Delonghi KG89 grinder that we bought him for Christmas so I could probably try that in order to rule out the grinder. Apologies for the length of this post but any advice & suggestions etc would be appreciated. Thanks Tony

@"Twotone2"#p19093 Does sound like the grinder could be the problem assuming you must have tried coffee from various reputable online sources.

Thanks @"DavecUK"#1, I've been looking at when I bought the grinder it was about around Feb 2016 so I've had it for six years now. I was thinking about just buying a grinder online or maybe asking the guys at ES for a loan of one to rule the grinder out. Tony Found the for sale thread. https://www.coffeeforums.co.uk/threads/sold-la-cimbali-magnum-£200.27266/#post-380772

@"Twotone2"#p19102 Did the problem start suddenly?

@"DavecUK"#p19105 No it's been ongoing for a good 18 months I'd say I was buying beans on-line from one of the roasters on here during the first lock-down and I was struggling to get decent espresso so just put it down to the beans at the time, the guy send me fresh beans and it was still the same so I bought from other places and really no difference then I started looking at the Elektra as the culprit but I'm thinking that I've not change how I do things I think the Elektra is working okay now so the only other thing is the grinder.

@"Twotone2"#p19111 When did you last check the burrs and that the screws were tight?

Elektra T1 Heat exchanger Espresso Machine Cool espresso

CoyoteOldMan

Twotone2 BTW, I’m a plumber/heating engineer

😃 That helps - at least you aren’t scared of pipes with liquid in them!

Twotone2

CoyoteOldMan That helps - at least you aren’t scared of pipes with liquid in them!

Just looking at the schematic if the blockage isn’t in the HEX then I think the pump is faulty. I’ve thought that all along and the engineers at Espresso Services said that the problem could be a faulty pump head.

I honestly can’t see that HEX being blocked with something as large as a coffee puck, from memory the heat exchanger is 22mm pipe or 28mm it certainly looks like 35mm to me but don’t know if it’s in a sort of sleeve?

Found this.

Heat Exchangers Accessible for Inspection, exclusive innovation to provide the control and cleaning of the heat exchangers.

https://www.theespressoshop.co.uk/Trade/Models.aspx?ModelID=3596

CoyoteOldMan

Twotone2 from memory the heat exchanger is 22mm pipe or 28mm it certainly looks like 35mm to me but don’t know if it’s in a sort of sleeve?

Is it ‘just a pipe/coil’, or is there a pack of fins/plates/smaller pipes inside, to increase heat transfer? It has to heat up water from a mains/tank supply at ~15-20 C to 95 pretty quickly… so I suspect there is something ‘inside’ the boiler to increase surface area with the hot boiler water. This could shrink the section quite significantly vs. the ‘large’ outside connectors.

CoyoteOldMan

Twotone2 Found this.

Heat Exchangers Accessible for Inspection, exclusive innovation to provide the control and cleaning of the heat exchangers.

This seems to imply that the HX can be removed - it doesn’t seem so from the images you posted (clearly soldered in place). Change in specs on a more recent model? Or is the large allen-key bolt at the top

removable to see what’s inside?
(Apologies - my training session at the gym is about to start - I’ll be back later, if this conversation is helpful)

Twotone2

CoyoteOldMan Is it ‘just a pipe/coil’, or is there a pack of fins/plates/smaller pipes inside, to increase heat transfer? It has to heat up water from a mains/tank supply at ~15-20 C to 95 pretty quickly… so I suspect there is something ‘inside’ the boiler to increase surface area with the hot boiler water. This could shrink the section quite significantly vs. the ‘large’ outside connectors.

Far as I remember it’s a just a pipe sitting in super heated water.

Twotone2

Found this too

"The 3-way is probably plugged up with old coffee residue as well and may need removed and soaked to clean it out. A good descale is probably in order as well unless he had a good softener on the supply line. You can check that a couple of ways. If you remove the cap from the group, there is a wire mesh filter. You can look at that for buildup. If you take the cup warmer off the top so you can get into the boiler, there is a cap on the heat exchanger that uses a large Allen wrench (unless they changed that between the old and new versions). You can unscrew that cap to see what the scale inside the heat exchanger is like. Finally, for the boiler, you will need to remove the vacuum breaker or heating element so you can see inside the boiler to inspect it for scale. If the heat exchanger inspection shows little scale, then chances are the boiler is in similar condition.

DavecUK

Twotone2 It could be a blocked solenoid valve, first thing is to try and get some descaler in the HX circuit and out the group. I doubt the pump is bad because it’s not making any funny noises, leaking and capable of 9 bar…as that is against an empty group, favourite is a blockage somewhere.

CoyoteOldMan

Twotone2 Far as I remember it’s a just a pipe sitting in super heated water.

At the very least, it must be folded on itself, as the inlet and outlet are on the same side - and you’ve got that “inspection” thing at the top… I suspect it may have some surprises. If you got some descaler in there, looking forward to hearing what happens tomorrow!

Twotone2

DavecUK It could be a blocked solenoid valve, first thing is to try and get some descaler in the HX circuit and out the group. I doubt the pump is bad because it’s not making any funny noises, leaking and capable of 9 bar…as that is against an empty group, favourite is a blockage somewhere.

Thanks I think I managed to get descaler into the HX.

I am going to leave the machine over night and empty it tomorrow and see what happens.

I replaced the group solenoid valve last week but there’s another one over at the pressure stat isn’t there?

Inlet solenoid valve no 6 in the schematic.

Could that one be blocked?

Tony

DavecUK

Twotone2 Possibly, that ones probably the autofll solenoid and normally open to the group. One thing is certain, there is an obstruction within the HX circuit somewhere.

Twotone2

CoyoteOldMan At the very least, it must be folded on itself, as the inlet and outlet are on the same side - and you’ve got that “inspection” thing at the top… I suspect it may have some surprises. If you got some descaler in there, looking forward to hearing what happens tomorrow!

There’s a few photos here of the inside of the boiler, there’s a lot of scale inside.

Still looking for photos of the HX from down the inspection hole, I’ll post some if I find any.

https://www.home-barista.com/espresso-machines/elektra-t1-deliziosa-t24744-10.html

Finally found a couple photos of the inside of the boiler showing the HX

CoyoteOldMan

Twotone2 There’s a few photos here of the inside of the boiler, there’s a lot of scale inside.

Indeed - and it looks like fish scales too! 😁

However, the boiler is not in the circuit that it giving you trouble… so even if it were full of scale, I’d expect you wouldn’t get hot enough water, but it wouldn’t affect the flow of water to the group/filter.

Twotone2

Good explanation of how a HX espresso machine is designed and how it works.

http://coffeetime.wikidot.com/heat-exchanger-machines-how-they-work

DavecUK

Twotone2 Good explanation of how a HX espresso machine is designed and how it works.

One of the best on the internet 😉

John_Yossarian

Twotone2 I hope that the night treatment of the HX has done the job (if the culprit were the HX) and the flow has been restored. I have cleaned a HX of an old Bezzera and although it looked quite bulky from outside the pipe inside (to ensure good heat transfer) was significantly smaller in diameter, not to mention that Bezzera implemented some PTFE to reduce the overheating. My point is that the HX could suffer in the scaling process.
The solenoid as per Dave’s comment is another possibility and might be easier to tackle with.
Let’s see whether your troubles are behind you first.
Fingers crossed.

John_Yossarian

Twotone2 This site was created by @DavecUK quite some time ago, and I suspect the explanations are his. As explanations go it doesn’t get better than this one.

Twotone2

Thanks guys, I’m hoping that I did manage to get descaler into the HX btw does anyone know how Elektra make their HX’s?

Looking at the photos above and the schematic it looks as though the HX is just a tube with three connections ie the hot and cold from the group and the inspection plug.

I can’t see how they would managed to put another tube inside the tube we can see going through the boiler given the connections?

Tony

DavecUK

Twotone2 The diagram is simplified, within the HC tube, there is usually an injector tube, the length of which is varied to give the right thermal characteristics. These can be in metal or PTFE.

Twotone2

DavecUK The diagram is simplified, within the HC tube, there is usually an injector tube, the length of which is varied to give the right thermal characteristics. These can be in metal or PTFE

Thanks so that would explain why it would block up.

So if the tube can’t be cleaned or becomes damaged (by descaling) then I’d imagine the only way to sort it would be a replacement boiler ergo BER?

DavecUK

Twotone2 So if the tube can’t be cleaned or becomes damaged (by descaling) then I’d imagine the only way to sort it would be a replacement boiler ergo BER?

WTF….No, just descale the brew circuit, you only need a new boiler if the HX tube has a hole in it….which yours doesn’t. Water is getting through to the group, while that is the case descaler can pass through as well.

There are times when the one way valve leaks, steam is formed in the HX and an airlock back through the pump and then the pump won’t refill the HX against pressure….but it’s rare and I don’t believe it’s your problem as I imagine you get the poor flow when cold as well.

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