# Gaggia way too hot? thermostat issue?



## Dorian (Sep 5, 2016)

Hi everyone,

I am still struggling with getting decent shots out of this Gaggia Deluxe I bought off ebay.

To me the machine gets way too hot, I can see steam coming out the group when I remove the PF. If I open the steam valve there s a good amount of steam coming out.

Shots come out very bitter, crema breaks up etc...

I removed the brewing thermostat and I can see it is the 107c one, it was wrapped in a thermal paste/paraffin? Not sure it was supposed to be like that, anyway I cleaned it and put it back, it seems slightly better.

Shall I try with buying another 107c or a lower one?

Thank you all


----------



## MartinB (May 8, 2011)

I've had a knackered brew thermostat a few years back. New thermostat sorted it!


----------



## cozzie21 (Mar 28, 2016)

I would be really curious to find this one out too. I have the same issue, it heats up straight to steam temp. It was a while ago and if i recall correctly, there are 2 thermostats, a water and a steam. I ended up changing them both but still have the same problem. I ended up catching upgraditis and put the Classic out to pasture. As i write this, I have an epiphany, is it the switch on the steam button that is broken rather than the thermostat?


----------



## Dorian (Sep 5, 2016)

These guys sell a 104c version, I may give it a try

https://www.bluestarcoffee.eu/gaggia-coffee-thermostat-104c-4057-p.asp


----------



## Dorian (Sep 5, 2016)

Well, I ve just ordered it, I ll report when I receive it.


----------



## bargi (May 7, 2020)

Dorian said:


> Well, I ve just ordered it, I ll report when I receive it.


 Any chance you can do a video of what you're seeing. I see steam even during a flush. Wondering if mine has gone to?


----------



## Dorian (Sep 5, 2016)

bargi said:


> Any chance you can do a video of what you're seeing. I see steam even during a flush. Wondering if mine has gone to?


 Yup, I ll see what I can do tomorrow..I should get the new part in a couple of days... Couldn t resist and got a silicon GH gasket too 😂


----------



## Agentb (Feb 11, 2017)

Have you tried using a thermometer to measure the temperature, straight off the shower screen into a polystyrene cup as described here.😺

https://coffeeforums.co.uk/topic/12300-polystyrene-cup-test-gaggia-classic/


----------



## allikat (Jan 27, 2020)

It depends on how much steam you see when you flush. When my thermostat was on the way out, I'd get steam nozzle (or hot E61) type steam jets during a flush for a moment before it cooled. Just some steam from the near boiling water is fine, it's a matter of magnitude really.

Do be warned that if it is on the way out, it can be a very quick step from "A bit hot" to "Doing 4-6-2 Pacific impressions", at which point replacing the thermostat is a required thing. Mine did that transition in under 2 days of use.


----------



## El carajillo (Mar 16, 2013)

The side of the boiler where the brew stat fits looks corroded as does the end of the stat. The stat relies on a very small area of contact to sense / transfer heat, the corrosion would not help. Paste / paraffin ?? it may be thermal paste NOT paraffin. Not strictly essential' but every little helps'.

Are you refilling the boiler after brewing / steaming ?? The boiler is very small and unless refilled steam is formed.


----------



## Dorian (Sep 5, 2016)

bargi said:


> Any chance you can do a video of what you're seeing. I see steam even during a flush. Wondering if mine has gone to?


 here s the video


----------



## Dorian (Sep 5, 2016)

El carajillo said:


> The side of the boiler where the brew stat fits looks corroded as does the end of the stat. The stat relies on a very small area of contact to sense / transfer heat, the corrosion would not help. Paste / paraffin ?? it may be thermal paste NOT paraffin. Not strictly essential' but every little helps'.
> 
> Are you refilling the boiler after brewing / steaming ?? The boiler is very small and unless refilled steam is formed.


 Thanks @El carajillo, yeah I m refilling it, not all the time though. I never had such problems with my old Classic Coffee ( I was stupid to get sell it a year ago )

Hopefully the new thermostat will fix the problem... and yes, it is thermal paste, I realise it now


----------



## bargi (May 7, 2020)

> 1 hour ago, Dorian said:
> 
> here s the video


 ahh, OK can see it steaming just sitting there an condensation on the water tank, wow pretty hot


----------



## Dorian (Sep 5, 2016)

Agentb said:


> Have you tried using a thermometer to measure the temperature, straight off the shower screen into a polystyrene cup as described here.😺
> 
> https://coffeeforums.co.uk/topic/12300-polystyrene-cup-test-gaggia-classic/


 Not yet I don t have the cup  but ordered the thermostat already so we see


----------



## Dorian (Sep 5, 2016)

Good morning guys,

Just as an update on this, I received and installed the new 104c brew thermostat but unfortunately I cannot any see any difference.

To me, the machine still gets too hot. I took another video after letting it on for 10 minutes, please have a look if you have the time, there s still a lot of hissing and steam going on.

At this point i d like to put it up for sale, but not sure if I should advertise it as spares or repair, I don't want to sell anybody a lemon machine. Please note I put the self priming valve back in place.






Again, thanks for your help.


----------



## AndyDClements (Aug 29, 2016)

@Dorian I think I know the answer to his but need to ask to clarify. During your ownership of the machine, which was it?: originally machine worked fine but then developed this issue, or, like it from the first use during your ownership.

I'm guessing from your first post (mention eBay purchase) it's been like this from the start. If that's the case then I think somebody has messed up the wiring and it's wired in such a way that it's working on the steam thermostat when it should be using the brew thermostat. The machine looks very clean inside, which could hint at it having been pulled apart. Find the diagram for that year of Gaggia Deluxe and check out the wires, I think you'll find a couple of them swapped to the incorrect places.

If however, it was working fine and has developed this problem during your ownership. How did it manifest, fine one day then like this the next, progressively worse over a few weeks, etc?


----------



## Dorian (Sep 5, 2016)

AndyDClements said:


> @Dorian I think I know the answer to his but need to ask to clarify. During your ownership of the machine, which was it?: originally machine worked fine but then developed this issue, or, like it from the first use during your ownership.
> 
> I'm guessing from your first post (mention eBay purchase) it's been like this from the start. If that's the case then I think somebody has messed up the wiring and it's wired in such a way that it's working on the steam thermostat when it should be using the brew thermostat. The machine looks very clean inside, which could hint at it having been pulled apart. Find the diagram for that year of Gaggia Deluxe and check out the wires, I think you'll find a couple of them swapped to the incorrect places.
> 
> If however, it was working fine and has developed this problem during your ownership. How did it manifest, fine one day then like this the next, progressively worse over a few weeks, etc?


 Hi @AndyDClements thanks I ll look into this. Actually the machine was pulled apart by myself as soon as I received, it was quite dirty and the dispersion shower was blocked. I think I rewired it as it was, but this does not mean it was properly wired from the beginning, so I ll look into the wiring now.

Although I think it cuts off the brew thermostat fine since if I switch to steam it heats up even more, but we ll see.

The only thing I want to point out is that I bent one of the element s pins when I rebuilt it, as per picture, but I m not sure this can have an influence.


----------



## MartinB (May 8, 2011)

Boiler terminals looks incorrectly wired to me. The front two terminals should be connected together by one single wire.


----------



## MartinB (May 8, 2011)

On the classic, the terminal that comes out of the thermal fuse is connected to the top left boiler terminal. top right is connected to the wiring from the steam thermostat.


----------



## Dorian (Sep 5, 2016)

MartinB said:


> On the classic, the terminal that comes out of the thermal fuse is connected to the top left boiler terminal. top right is connected to the wiring from the steam thermostat.


 Thanks for having a look at this @MartinB

This guy though got the same machine and I d say it is wired just like mine

https://images.app.goo.gl/VuyVnsQK8tuC81AH6


----------



## MartinB (May 8, 2011)

Dorian said:


> Thanks for having a look at this @MartinB
> 
> This guy though got the same machine and I d say it is wired just like mine
> 
> https://images.app.goo.gl/VuyVnsQK8tuC81AH6


 Is that a 110v or 240v machine in the pic? Depending on voltage the elements (110v I think!) are either wired in series or parallel from memory.


----------



## Dorian (Sep 5, 2016)

MartinB said:


> Is that a 110v or 240v machine in the pic? Depending on voltage the elements (110v I think!) are either wired in series or parallel from memory.


 It should be 240 as far as I know, the pic was posted in an Australian forum. Mine should be the same I bought it from the UK.


----------



## Chriss29 (Oct 21, 2020)

Did you ever discover a fix Dorian?


----------



## Chriss29 (Oct 21, 2020)

The solution to my problem with the same symptoms was a new brew thermostat. In fact I took the opportunity to purchase the 100c thermostat instead of the 107c and have to say I prefer it. With hindsight I should have got a pid as that's next on my list 😀


----------

