# Sage Oracle not reaching temp



## Rob880

Hi, I have a Sage Oracle. Yesterday, steam started coming from the main dispenser and continue for a while after it was turned off. This morning I descaled it which seemed ok, but once it had finished it started heating the water as normal but wouldn't go above 70 degrees. I've turned it off a few times and left it and when I turn it on the reading climbs normally but never gets past 70-73 degrees no matter how long I leave it. It has also stopped making the rumbling sound that happens when the machine is turned on.
need coffee ?


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## Roguejackal

Have you tried a reset back to factory settings?


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## jamster

Same thing happened to me:

https://coffeeforums.co.uk/topic/49254-dual-boiler-no-longer-heats-up/

Sent from my SM-N960F using Tapatalk


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## lake_m

How old are these machines? Are they under warranty?

Must be something failed on the control circuitry if it's actually getting up to 70 degrees.

Disappointing - especially over Xmas.


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## jamster

About 3.5 years old.

I have been on to Lakeland and they are sorting me out. unfortunately no espresso over xmas tho.

Sent from my SM-N960F using Tapatalk


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## Nick#

Hi Rob, I realise this is an old post but same problem just happened with my fairly new Oracle, straight after doing the first descale. - Stuck at 70 deg. Just wondered how this got resolved in the end for your machine?


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## Nick#

Nick# said:


> Hi Rob, I realise this is an old post but same problem just happened with my fairly new Oracle, straight after doing the first descale. - Stuck at 70 deg. Just wondered how this got resolved in the end for your machine?





Spoiler



Success! During the first descale cycle I remember noticing that there was no liquid flow when I opened the two valves after both the descale cycle and also the subsequent rinses. So I think one or both of the boilers must have been air locked and/or the valves clocked with some calc. So when I went back to normal operation initially, I think the boiler(s) must have been only partially primed resulting in the water temperature not reaching target and getting stuck at 71-72 degrees and continually trying to heat to set-point. So.... After leaving it overnight I repeated the whole descale operation to try to dissolve any bits of calc loosened by the first attempt and also during the 20 minute timer, I cracked open the steam valve to the manual position for a couple of seconds in case this helped to prime the boiler Then when directed to drain the boilers after the descale and each subsequent rinse, I got plenty of flow of hot water and steam when I opened the two valves. When It went back to normal operation I noticed that it drew approx a quarter of a full tank of water to fill the boilers which it had not done when I had the problem, then it heated up fully to the target temp. So I believe this issue of not reaching temperature was purely down to lack of priming and removal of air from the boilers, possibly caused by blocked or air-locked drain valve in my case.


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## jm-darcy

Nick# said:


> Spoiler
> 
> 
> 
> Success! During the first descale cycle I remember noticing that there was no liquid flow when I opened the two valves after both the descale cycle and also the subsequent rinses. So I think one or both of the boilers must have been air locked and/or the valves clocked with some calc. So when I went back to normal operation initially, I think the boiler(s) must have been only partially primed resulting in the water temperature not reaching target and getting stuck at 71-72 degrees and continually trying to heat to set-point. So.... After leaving it overnight I repeated the whole descale operation to try to dissolve any bits of calc loosened by the first attempt and also during the 20 minute timer, I cracked open the steam valve to the manual position for a couple of seconds in case this helped to prime the boiler Then when directed to drain the boilers after the descale and each subsequent rinse, I got plenty of flow of hot water and steam when I opened the two valves. When It went back to normal operation I noticed that it drew approx a quarter of a full tank of water to fill the boilers which it had not done when I had the problem, then it heated up fully to the target temp. So I believe this issue of not reaching temperature was purely down to lack of priming and removal of air from the boilers, possibly caused by blocked or air-locked drain valve in my case.
> 
> 
> 
> Did you fix this? I have managed to fix this on a number of machines. It is down to trapped air. Let me know if I can help.


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## DennisL

Anyone that has a solution for this? I descaled my machine yesterday and now it seems I cannot get over 70-71 degrees. I've tried cutting the power over night and I've done the descaling program an additional two times with no success afterwards. Still stuck at 70-71 degrees..


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## Goodfella

Did anyone else get this resolved? I have encountered the exact same issue today after a descale. It just stops at 70/71 degrees.

Cheers

Ross


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## SO8

Mine has just stopped at 71c too ! I wish I had never started the process on a Sunday !!

What did people do to sort this apart from leaving overnight ?

Have Sage given advice or do they have to send someone ?


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## jamster

I read this on another forum:

It's most likely an airlock in the system... With the machine off and cool, open and drain the steam boiler (one on right). With the drain screw still open, turn on machine and you should her the pump run; wait till you can see water coming out - and let in run for a couple of seconds while you close the screw (you can remove the drip tray screen to see better). Let it fill, and see if it comes to temp. If not, repeat the process with the brew boiler screw on left.

Source (https://www.home-barista.com/espresso-machines/breville-dual-boiler-five-years-on-t45361-840.html)


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## SO8

Great, thanks. I'll try that.


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## SO8

Working !! Persistance pays and thanks for the advice.

A comination of what is above worked. One boiler didn't fill properly, then the other one ... aaargh ! Time consuming but there in the end.

Leaving the valve open and restarting the process afterwards got both boilers running. It was clear at the end by the amount of water that came out when I drained them, that initially they had not refilled properly.

Once, after both boilers were finally working on the 1st cleanse of descaler, I decided to go with that and then manually empty the tanks by steam and portafilter. I did another 2 tankfulls 'manually' and the water did not smell of chemicals so am happy it will make ok coffee !

I won't be rushing to descale next time !! Especially as the warning hadn't actually come up and I was trying to be good and keep it uber clean. 3.5 months old, no descale warning, but next time I will not rush and know what to expect.


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## Goodfella

That's great news.

So did you run the descale programme again or just tried the method above?

Cheers

Ross


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## Goodfella

I have tried all the various advice with no luck so it's coffee classic to the rescue on Friday.

It does make me uneasy that descalling the machine following Sages instructions has led to either a probe or thermo switch needing replacing.

Ross


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## Macbeth

New poster here but wanted to chip in with my experience to help others.

- New (2 month old) Sage Oracle

-attempted a descale; temperature wouldn't go over 70 degrees or so afterwards.

- spoke to Sage support who advised it is probably an air bubble. They emailed me instructions to resolve - basically to half fill the water tank, tilt the machine 45 degrees forwards and switch on, holding until temp > 70.

- this worked, I have coffee again

I'm not sure that I've properly descaled the machine so will probably try to run the program again in a few days. But it seems that the instructions to only use 1 litre of descaler solution could be problematic....the descaler programme seems to require more....and I'm questioning whether that is what caused the air bubble....


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## ajohn

The tanks hold 900ml so a 1L is probably a bit low. I'm no sure how low the tank can go before it comes up with fill. Maybe mix to 1.1L.

I use a DB but tanks and plumbing etc are the same as the Oracle. I can't recollect seeing mention of this problem before. I wonder if it's down to the instructions in the manual. It starts off with have the machine off for 4hrs. Ok that drain will be cool but the machine reheats when the descaler goes in so when that is drained it will be hot.

I let the machine heat up and then go into descale. I drain the brew boiler 1st as well to make sure it does drain. The left hand screw. It's pretty obvious when the steam boiler drains, right hand screw. The brew might need the 1 cup button press.

I also allow the machine to be on for the full 20min on each flush and exit after 20min on the last one. It's possible to speed up the flushes - as mentioned in the manual, skip by pressing the one cup button.

I've also descaled by not draining the descaler after the first 20min to allow it to be in the machine for another 20min. This was because the single 20min wasn't removing all of the scale. Long story I wont bore you with.


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## Frog

Macbeth said:


> New poster here but wanted to chip in with my experience to help others.
> 
> - New (2 month old) Sage Oracle
> -attempted a descale; temperature wouldn't go over 70 degrees or so afterwards.
> - spoke to Sage support who advised it is probably an air bubble. They emailed me instructions to resolve - basically to half fill the water tank, tilt the machine 45 degrees forwards and switch on, holding until temp > 70.
> 
> - this worked, I have coffee again
> 
> I'm not sure that I've properly descaled the machine so will probably try to run the program again in a few days. But it seems that the instructions to only use 1 litre of descaler solution could be problematic....the descaler programme seems to require more....and I'm questioning whether that is what caused the air bubble....


I've got the same issue right now. I've got a couple of questions regarding your solution:

-Did you need to leave the machine shut off for longer to cool down?
-Did you need to do anything with the valves? Were they shut while tilting?


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## woodbar

Probably NOT applicable to the various problems here but on three separate occasions when I have started my Oracle it has only heated to 72 deg then stopped heating. This was not following any descale operation.

The culprit apparently was me! It seems that I must have nudged the steam control up to manual whilst reaching around the machine to get something from behind. After panicking that my machine was defunct luckily I noticed the the steam control was not in the off position and reset it accordingly. However the machine did not continue heating until I used the hot water button to draw of some water whereupon the machine resumed heating up to the set temperature - phew!

The descale procedure does seem a bit hit and miss - I used the specified 1 litre of water the first time and the machine stopped doing anything part way through with a "fill tank" error? I topped the tank up with a little water, when I noticed it, until the error disappeared and the descale appeared to complete OK.

Subsequently I have used Puly descaler which requires 1.5 litres of water so have not had that problem again although I now always need to use the 1 cup button to get the flow started from the brew boiler when trying to empty it?


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## ajohn

The DB is the same. Sometimes the brew boiler drains and sometimes it needs the 1 cup button press to get it going. It's probably down to water and surface tension - just needs a bit of help to get it going. The drain pipes are narrow dia. They have to take high pressure so they use the same pipe and connectors that are used elsewhere.

The boilers hold ~900ml so 1l is a bit close. I used 1.1L. Sage's own engineers use Puly descaler.

The DB uses the same internals. Some people don't descale and say that is when the machine has problems. They may be using certain brands of bottled water to avoid descaling. It's the fact that they aren't descaling which probably causes the problems. Same could happen with tap water if not done often enough. Sludge can collect in the bottom of the boilers and descaling probably cleans the level probes in them. Problems like that can cause the valve error that can crop up during descale - tanks not draining when they have.  If stuck there is a video on youtube concerning descaling the very early DB when it didn't have the drain taps.

I've never had my machine stop fully reheating the water after a descale. I don't skip out of the procedure early and always allow the full 20min before dropping out.  But maybe I have been lucky. Other than here and recently I haven't seen any mention of this problem. Having a tap open causing it does make some sense as the machine can decide to put water in the boilers at any point in time even when powering up. However when steam is being drawn it doesn't. It probably does at some point if enough has been drawn off and that seems to be way way more than what people use in practice. It may decide to add water during a descale.

When people have steam problems Sage tell them to descale the wand. So when I descale I use the steam selector briefly a few times and just let a bit of wet stuff come out rather than steam, say 5 min apart.


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## Frog

I didn't skip out on any descaling, in fact I performed a descale early (after 6 months with the machine).
Of course since I bought the machine refurbished (from the German service partner) there might have been some built up before resetting the counter.

Since I did not need to go into a detailed description when calling the service hotline I'm assuming that the error is not too uncommon.

The solution that worked for me was opening both valves and letting the machine sit like that overnight. After turning the machine on in the morning I closed the valves again and tilted the machine forward 45 degrees and held it like that while the tanks refilled.
The next descale in the afternoon went through without any issues.

The only thing I keep wondering about: following the onscreen instructions on my oracle touch I first filled the tank with a mix of descaler and 1 liter of warm water and then filled up the tank to the max. Only after that did I start the next step of the process. Since this increased the dilution of the descaler quite a bit I'm wondering if there's a translation issue at work here or if the Oracle Touch really need this weaker solution.


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## ajohn

As far as I know the descaler should be mixed according to instructions so the boilers are drained and filled with that. Then before flushing the tank is swilled and filled with clean water. After that drain and fill twice with the clean water.

The DB does this with a button push for each stage. That starts a 20min timer, the tanks are drained after that has elapsed so the machine is filled with descaler for 20min. I leave it for 20min when it's refilled with fresh water as well.

 So another way of putting it. Put the descaler solution in the reservoir. Select descale mode. Drain the tanks. Then in my case press the button which starts the 20min timer and so on.


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## woodbar

This can all get a bit confusing - not helped by the fact there seems to be at least 3 different versions of the user manual for the Oracle with slightly different instructions!

I have now had an air locked pump - making a very nasty noise - but as I had just done a clean cycle, with Puly Caf, and also fitted a new water filter I had a pretty good idea where it would be! Took the filter out and soaked it again as well as agitating it vigorously in a bowl of water, refitted it and after lots of gurgling and pumping managed to clear the air lock.

@FrogAs for the descale procedure I would not be topping up the tank having mixed the descale solution as you are immediately diluting it so there was no point measuring out the 1 litre in the first place? As mentioned above the boilers take about 900ml so, allowing for error and level switch sensitivity, you probably need about 1.2 litres of descale solution to avoid the "fill tank" error. As it only fills the boilers once with descale solution then anything over the 1.2 litres or so is left in the tank and just wasted when you come to rinse the tank for the flush cycles.

One thing which seems odd in the instructions is it says to not start a descale until the machine has been allowed to cool for 4 hours - presumably because of the possible danger of releasing steam through the drain valve? Then after the descale cycle has finished and before flushing it tells you to open the drains, one at a time, while the machine is still obviously hot! Perhaps the temperature of the steam boiler is held at a lower value for descaling so it does not actually produce (much) steam?

I must admit I always have my fingers crossed when doing a descale as it seems that for a large number of machines/users this is where things go wrong with blocked valves/tubes/failing to drain etc.


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## ajohn

The old filters needed a pretty good soak to fill them. The new ones may be worse and need deeper water.

The leave to cool confuses me too. However next time I am going to allow it to cool significantly. I descaled once and had doubts about the brew boiler draining completely so started draining that first. Didn't work out well this time and I am wondering if it was down to the steam boiler being at full heat. The brew water passes through a heat exchanger in the steam boiler before going into tbrew one. It's one of the reasons they have good thermal stability on brew water. The control is unusual as well. 2 sensors.

If I have any doubts about the brew boiler in particular not draining completely I go through the whole thing again. The first time I did that it had an interesting effect. The boiling noises trickled off to nothing as the temperature reached the set point. It didn't before. It was a UK refurb machine so I can assume that it was descaled before I received it and I descaled it anyway as soon as it arrived. I can only assume that this did not remove all of the scale - the 2 on the trot did. Before that scale was just building up on scale that was already there. Scale on heating elements means they don't heat as effectively and water is inclined to boil off where there isn't any - upsets the PID as a result. The scale can flake off and sludge up the bottom of the boilers which can make the machine think the tanks haven't drained. The level probes may need cleaning. In short problems while descaling are likely to be doing it too late.

I live in B'ham. Very soft water but having mentioned this on here some one from Severn Trent commented that when short they abstract water from all sorts of places to maintain the supply. So at times my water may well be harder than it should be. We never ever descale a kettle as several years of use doesn't leave a noticeable deposit. My steam boiler does scale. I've set my machine to a couple of grades harder than the test strip indicates. I've toyed with the idea of setting it as high as it goes. I might on the next descale to see how long it takes.

I have had problems with what looks like scale sludge on the ports of the solenoid valve. It caused the dreaded solenoid rattle. I dismantled and cleaned it off with my thumb and that cured that. I have to wonder if the clean me indication is reliable so do that once a month along with cleaning the shower screen and behind it - I do that before the backflush as no point in blasting what is there back into the machine.


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## woodbar

Yes mine are the new type, very expensive, filters! I have just recently fitted a newer type under-sink filter feeding a separate tap I use for the Oracle & the kettle which has the same functions as the Sage filter - carbon + Ionized resin beads - and is about 8 times bigger and less cost! I therefore probably won't bother with the Sage internal filters anymore. I have tested the water hardness post filter and it comes down to 120 which is pretty reasonable I think, only slightly hard needing occasional descaling of the Oracle.

Talking of which I descaled it this afternoon and I think my theory was correct - the descaling temperature for the steam boiler is kept at a lower temperature which is why you initially have to wait for it to cool before the initial drain but NOT after the descale. I judged this by the fact the cup warming shelf really only got slightly warm throughout the whole routine. I must confess I did not wait for the full 20 minutes during the flush cycles - the heating indicator goes off after 12 minutes so I jabbed the button to continue to the drain stage at that point - after all if you wait for the 3 lots of 20 minutes plus preparation time, filling, draining and rinsing the tank etc. you can kiss goodbye to the best part of 2 hours!

I think I feel a bit more confident about the descale procedure now.


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## ajohn

I suspect the allow to cool before starting a descale may relate to draining the brew boiler. On a DB steam gushes out when the descaler and the flushes are drained so must be over 100C. Past the actual 20min with descaler in theory says the boilers will be up to temperature in under 5min. I may try draining these soon after boiling noises have ceased.

I've concluded that my idea of running it with descaler in for 2 20min periods doesn't work as well as I would like. 2 fresh lots did clear an excess in my case. Refurbed machine that even after a refurb descale and one when it arrived still left scale in. That was pretty obvious from PID behaviour after I did 2 on the trot.

 Problem with a refurb really. I have no idea what the first owner did. Perhaps they lived in an area where the water is so hard Sage suggest using an alternative source. Perhaps they used bottled water and thought no need to descale at all. Or maybe the machines indication interval isn't correct. I get very soft water out of the tap but a man from Severn Trent warned me that when water is short they abstract from other sources that are not soft. Scale and sludge from it and other things dissolved in water don't prevent the machine from working - eventually it will if it accumulates or gets in an unfortunate place such as in a solenoid. Doesn't matter what make of machine it is.

One thing that could explain a very unfortunate failure where steam wont be produced any more as the boiler isn't heated at all is the dreaded valve error during a descale. It means the machine thinks that the boiler hasn't drained. This can be down to 2 things one is sludge in the boiler. The other level probes needing cleaning. What happens if some one powers off and brings the machine up in it's normal mode and it assumes there is water in the boiler? If it turns the heater on and a thermal fuse will blow. LOL The crazy thing is that lack of descaling will cause this sort of problem. The only solution if it happens is a direct into the boilers descale as per a youtube video on an early DB that didn't have the drain facility. The other crazy aspect is that all Sage machines are easy to descale. Most need spanners yet buyers are reluctant to do it - some times on a DB as they are worried about getting the valve error. People who spend £1000.s on a machines go to some length to avoid scale all together. At that level people have more sense - maybe.

The other aspect on all Sage machines is the clean me indication. It is too long. Seems to be ~200 shots. Not sure. Weekly or bi weekly is a better option for a trouble free life.


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## woodbar

Yes 200 coffees before a clean seems pretty ridiculous - I do mine roughly bi-weekly with Puly caf which would probably work out to about 40 coffees.

I do the back flush about every other day or when I remember it - whichever is sooner!


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## TonyD

I folks. I have the same temperature issue as many on here after descaling. Tried all your tips and repeated them as suggested by the Sage team. Still no joy. Their UK repairer suggests it's either the level probes or the thermal fuse. If anyone has instructions on how to change these I'd be very grateful. Regards, Tony.


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## TonyD

To add to my note above, I've just turned the machine off and opened the left-hand drain plug, but no water has come out. Does that suggest a different problem please? Many thanks, Tony.


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## dutchy101

The 200 shots before a clean isn't necessarily 200 coffees being made. I pull a warming shot to heat up the portafilter and basket, then I'll make a coffee and then I'll pull a further shot and wash the screen with a brush whilst the water flows out. That's 3 shots pulled for one coffee. On this basis I'd have made 66 coffees when the clean me function kicks in as opposed to 200. Arguably still too many, but I take off the shower screen every week and soak in Puly Caff with the steam tip and basket.


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## woodbar

Yes, everyone seems to have their own take on interpreting Sage instructions for cleaning etc.

I just do the clean cycle every 2 (mm, maybe 3😉) weeks and I don't always remove the shower screen afterwards as whenever I do it is always spotless from the Pulycaf.

I don't need to clean the steam tip as we don't ever use milk - I just steam a jug of cold water to temperature every week or two just to keep everything "exercised" and in working order!


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## J645

Just buy a proper Italian machine lelit Elizabeth dual boiler check it out at Bellabarista.co.uk👍👍


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## TonyD

Helpful comments are wonderful to receive, but phishing, as I'm sure you can imagine, is never welcome. £1800 machine. The way forward will never be to skip it..


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## woodbar

Best just to ignore it.


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## TonyD

Hi folks. Further to my comments above.

Had the same problem with my Sage Oracle - wouldn't heat beyond 70 degrees following a descale. The root-cause issue was a blown thermal fuse. Detailed instructions on how to change the fuse can be found here:

https://www.home-barista.com/repairs/breville-oracle-bes980xl-thermal-fuse-replacement-detailed-disassembly-t58936.html

I've also added some additional tips at the end of littleyip's thread. Repair took around 3 hours and cost just £0.80.

Delighted to say I now have coffee again..


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## stevegold6

Had same problem. Descaled machine and then would not heat past 73c.

Noticed no water draining from right hand drain.

With machine at 73c I opened the right hand drain and turned on the steam wand, water started to drain so tightened the screw turned off the wand and machine went to normal temp. Hth.


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## Sarah Holli

I have the same problem, descaled as per promts on machine, then not getting past 73 degrees. Right hand boiler has nothing to drain. How did you get the steam wand to operate / turn on when it was below temperature please?


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## Sarah Holli

stevegold6 said:


> Had same problem. Descaled machine and then would not heat past 73c.
> 
> Noticed no water draining from right hand drain.
> 
> With machine at 73c I opened the right hand drain and turned on the steam wand, water started to drain so tightened the screw turned off the wand and machine went to normal temp. Hth.


 I have the same problem, descaled as per promts on machine, then not getting past 73 degrees. Right hand boiler has nothing to drain. How did you get the steam wand to operate / turn on when it was below temperature please?


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## stevegold6

Hi Sarah.

My oracle was on and showing 73c , I opened the right hand drain and put the steam control to manual. When water started to come through the drain I tightened the screw and turned off the steam control.

Good luck.


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## Guest

Hi! We had the same issue of the coffee machine not reaching the temperature. The steam toggle (far right for the milk frother) has to be on auto for the machine to heat up fully. If it's on manual, it will stop heating at some point and not continue.!!


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## stevegold6

My machine stopped at the dreaded 73c after descaling. Tried my own advice and failed to get it up to temperature.

Ended up checking the solenoids on the steam side, both were in pristine condition.

Pulled the water pipe to the steam boiler and siphoned water to top of pipe and reconnected. Machine immediately started getting up to temperature.

Really happy I didn't have to look at the thermal fuses.

Happy again 😀


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## Wadsad

stevegold6 said:


> My machine stopped at the dreaded 73c after descaling. Tried my own advice and failed to get it up to temperature.
> 
> Ended up checking the solenoids on the steam side, both were in pristine condition.
> 
> Pulled the water pipe to the steam boiler and siphoned water to top of pipe and reconnected. Machine immediately started getting up to temperature.
> 
> Really happy I didn't have to look at the thermal fuses.
> 
> Happy again 😀


I'm having the same issue unfortunately and already tried everything except for this, but:
Which one is the water pipe? You pulled the waterpipe from the brewboiler or from the pump?


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## Smark

YES! This solved my issue!!!! I just thought that I had melted the thermal fuse and that I would have to send it in for another repair. I had air bubbles!!!

I believe this has been a huge problem for many people....



Macbeth said:


> New poster here but wanted to chip in with my experience to help others.
> 
> - New (2 month old) Sage Oracle
> 
> -attempted a descale; temperature wouldn't go over 70 degrees or so afterwards.
> 
> - spoke to Sage support who advised it is probably an air bubble. They emailed me instructions to resolve - basically to half fill the water tank, tilt the machine 45 degrees forwards and switch on, holding until temp > 70.
> 
> - this worked, I have coffee again
> 
> I'm not sure that I've properly descaled the machine so will probably try to run the program again in a few days. But it seems that the instructions to only use 1 litre of descaler solution could be problematic....the descaler programme seems to require more....and I'm questioning whether that is what caused the air bubble....


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## Morten Fabricius Olesen

Solved my 72 C problem on an older Oracle.

After several attempts of descaling with only a little or no drainage when opening the drainage valves, the temperature would not go above 72 C.

I took out all 5 sensor rods in the boilers. A very simple operation. 

There was significant scaling on all the rods which I removed. Especially the short water boiler sensors where completely covered and probably not functional.

Secondly I could shine a light through one sensor hole and see through another. I could see some loose scaling near the openings in the lowest part of both boilers. The drainage was blocked in the steam boiler and partially blocked in the water boiler. I injected some descaling solution into the boilers, waited a few minutes, gently moved the whole machine to swirl the fluid, poked a little at the blocked drainage opening inside the boiler with a wooden peg, and finally the drainage was unblocked. Did some more descaling and rinsing using a plastic tube and siphoning. 

Reassembled everything and the problem was solved!

A somewhat isolated observation: I'm not sure, but in normal operation possibly the steam boiler is filled first by the pump and only then, the water boiler is filled. The fill lines seem to be in series


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