# Fitting a PID to the Kitchenaid Artisan.



## Norvin (Sep 10, 2014)

Recent discussions on fitting a PID to the Kitchenaid Artisan espresso machine in another thread has piqued my interest. So I thought that I would spend a few hours in the garage and see if it was possible. It turns out that fitting a PID is very straightforward, no more difficult than fitting one to a Classic.

I'm posting this as there is so little information on the Kitchenaid and it may help others thinking of giving it a go.









Some notes;




The little PCB board that I had always assumed directed current to each boiler in turn via the twin point relay does nothing of the sort. It is fitted in parallel to the mains supply input but God knows what it does, possibly reduce interference, suppression, prevents arcing across the points, keeps the polar bears away, sends reports of your coffee drinking habits to the Chinese, who knows? It does not feature on the wiring diagram and the machine still functions even if it is unplugged.



The switching of the current to the boilers is done via the twin point mechanical relay, it can be left alone in the conversion but the constant clicking of the points everytime the brew element is activated and deactivated by the PID many times per minute can be annoying. The relay can be bypassed easily so that both elements are on at the same time, in which case the current draw when the machine is switched on is 2,370watts. The current draw soon settles down as everything gets up to working temperature.



There is probably room to fit the PID and SSR inside the case. Once set, who changes the temperature anyway? That would mean that an enclosure would not be needed for the PID The top is easily removable for resetting boiler target temperature if desired, although you wouldn't want to do that on a daily basis.



Pickup points for the connections are easily accessed once the upper case has been removed.



Because the steam boiler is separate from the brew boiler the standard PID can't be used to control the steam temp via the alarm function, a separate PID would be needed.


All in all, the Kitchenaid is a very nice and very underrated machine. It is basically a twin boiler Classic, and contains items made by Gaggia. It has most of the desirable features of the Classic - boiler, OPV, three way solenoid, with a few more; nice cast metal case, twin gauges, steam boiler, articulated steam arm (take away the plastic panerello tip from the steam arm and there is no real need to fit a later Rancilio arm), you don't have to wait for the boiler to heat up to get steam after pulling a shot, and best of all they're cheap secondhand! I bought mine for £20, second hand ones usually have problems with a leaking steam boiler gasket and consequential corrosion of the boiler screws and monkey metal case with flaking of the paintwork.

If you are handy and are on a budget, you would be hard put to better the Kitchenaid Artisan.


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## NitJay (May 18, 2020)

Interesting info - someone asked me about parts for this the other day, I had to look it up they seem pretty rare (in the UK at least) I was very intrigued by the twin gaggia classic boiler setup.

They seem to have a bad reputation for reliability but surely you can just replace whatever goes wrong like on the classic?

I might keep an eye out for one of these they seem to sell for very little.


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## Norvin (Sep 10, 2014)

I get the impression that their reputation for unreliability stems from steam boiler problems. The steam boiler seals fail due to heat from a combination of being kept at steam temperature and people not refilling the boiler after steaming (no autofill, you have to do it manually). The boiler leaks cause corrosion and electrical problems. Kitchenaid don't want to know, so the expensive toy goes on ebay. Change the seals and let it dry out and you should be good to go (probably).

I had a big problem with the boiler allen screws being corroded in, most of the screw heads snapped and had to be drilled out (about nine of the eleven screws from memory), but it is likely that the corrosion on mine was more advanced than others. Change the seals at the first sign of a leak and it should be reliable, most of the components are the same as or very similar to the Classic. Remember that this was/is sold as a quality machine for a premium price. Even if you can't fix the steam boiler, if you only drink espresso you still have an espresso machine just as good as or better than the Classic, just disconnect the steam boiler element and fill solenoid.


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## NitJay (May 18, 2020)

Really good info thanks, I've got a feeling the person who asked me about servicing this will be getting back in touch with me soon ( they bought an ebay 'for parts' special) this will help them out.

In the meantime I'm off to look for some broken KitchenAid Artisans in need of some tlc 🤔


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## whosefucoffee (Jun 23, 2020)

Norvin said:


> The little PCB board that I had always assumed directed current to each boiler in turn via the twin point relay does nothing of the sort. It is fitted in parallel to the mains supply input but God knows what it does, possibly reduce interference, suppression, prevents arcing across the points, keeps the polar bears away, sends reports of your coffee drinking habits to the Chinese, who knows? It does not feature on the wiring diagram and the machine still functions even if it is unplugged.


 I've had a good poke around inside mine now, and as far as I can see the PCB is just used to shut the machine off after a set time. There is a feed to it from the pump which I assume resets the timeout. Probably not a bad idea to help try and save the steam boiler.

I want to PID mine now, can you tell me which one you used ?


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## Norvin (Sep 10, 2014)

The PCB is wired in parallel so can't shut off the power to the rest of the machine. Machine works even when it is removed and machine does not shut off when left. I thought that it may be there for arc suppression but there seems to be just as fat a spark across the relay points with it or without it connected.

I used an ordinary Rex c100 PID with SSR and k type thermocouple, just the same as you can use with the other single boiler Gaggias. There is room in the body to house them, they didn't overheat in there over the few days that I experimented with it.

Having played with a Classic over the last week, I prefer the Kitchenaid as you don't have to wait for the boiler to heat to steam temperature while your espresso goes cold.

It's now back in the garage, if anybody wants to make an offer for it...


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## whosefucoffee (Jun 23, 2020)

Norvin said:


> The PCB is wired in parallel so can't shut off the power to the rest of the machine. Machine works even when it is removed and machine does not shut off when left. I thought that it may be there for arc suppression but there seems to be just as fat a spark across the relay points with it or without it connected.


 Maybe my PCB is different then, because it would stop working if I disconnected it, as it switches the mains power coming into the machine.

Thanks for the PID details, I'm in 2 minds whether to go the Arduino route so that I can replace the temp gauges with digital screens, but one of these would be quicker in the meantime 🙂


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## Norvin (Sep 10, 2014)

That explains the confusion, mine is different. It does not have that PCB, only a long thin one wrapped in some insulating material attached to the loom via a plug.


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## angio (Jul 10, 2015)

Just wanted to add a little bit of information to this thread as what has been posted so far by @Norvin has been incredibly useful. I've bought two of these Kitchenaid espresso machines hoping to make one single functional one from both. Both were £30 each and both of which featured failed steam boiler gaskets. These machines do seem to be bought by people who want them to match their stand mixers but don't necessarily know (or care) about how to look after them properly. My red one is from around 2013 and the crream one is from around 2016.

The machine with the shrink wrapped PCB is the older 2013 version and that shrink-wrapped PCB features an MOV (metal oxide varistor) which is used to protect the circuitry from the repeated switching between boilers by the relay. This version features the adjustable OPV that can be adjusted but feeding the 5mm allen key up the hole that the excess water flows back into the water tank - wish i had read about that before i did my 9Bar adjustment!

The other machine from 2016ish is the equivalent of the 2015 type Gaggia classic and features some of the same bits like fixed OPV, pushfit connectors for the internal tubing and the momentary switch buttons on the front (power and hot water from steam boiler on the kitchenaid are both push and hold buttons) and the PCB in @whosefucoffee 's pictures controls those functions which is why theirs wont work without the PCB connected.

I have my red one up and running and it's brilliant and have just received a PID kit from amazon for only £20 but i'll need to get an m4 threaded thermocouple as the one in the kit is an M6 and wont fit in the place of the original thermostat. My biggest gripes are that the temperature dials on the front are nice to look at but are really not that accurate, the steam boiler has no override so it will always come on, even if your only after an espresso and the water tank is hidden away so you really have to remember to check it has enough water to not run dry and kill the steam boiler.

I'm planning on replacing the temperature dials for LCDs driven by an arduino plus a water level sensor as the next step after the PID upgrade followed by a rancilio silvia v3 wand swap in.


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## Norvin (Sep 10, 2014)

Thanks, I've never seen the later type so that clears a few issues up.

You can take off the threaded connector on the thermocouple by carefully de-crimping it and pulling the cable out. You can then trap the little blob of solder at the end of the cable between the boiler and thermostat with a little processor thermal paste.


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## MrExperience (Jan 14, 2021)

Hello! May be off topic, but anyone knows of there's a guide on how to replace the seals of this?, I bought mine off of Facebook marketplace a couple weeks ago, and today it just tripped my breakers. I opened it and saw there's a lot of condensation in there. Thanks in advance


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## HDAV (Dec 28, 2012)

MrExperience said:


> Hello! May be off topic, but anyone knows of there's a guide on how to replace the seals of this?, I bought mine off of Facebook marketplace a couple weeks ago, and today it just tripped my breakers. I opened it and saw there's a lot of condensation in there. Thanks in advance


 @Norvin is the expert but look on ebay for a seal kit and the parts diagram explains most of how it comes apart, probably need to dry the elements out possibly replace the boiler if its bad


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## Norvin (Sep 10, 2014)

It is most likely that the steam boiler is leaking at the main gasket. If you are really lucky you may be able to replace it by removing the top case cover and removing the four boiler bolts from above. The seal is the same as for other Gaggia boilers. In practice, you may well find that the bolts are seized in place due to long standing corrosion and more extensive work is needed to dismantle it. The boiler elements will need drying out but the boiler probably doesn't need replacing.


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## Norvin (Sep 10, 2014)

Having sold the old Kitchenaid, I have bought another. This one is the later type that caused the previous confusion in this thread. It was bought cheap as it was tripping the electrics, the seller also 'forgot' to mention that the hot water switch was jammed on. As it is the later type I thought that I would update this thread to give some additional information.

I stripped and renewed all of the seals, the steam boiler seal had gone but all of the screws came loose really easily. Refurbishment was straightforward except that the three springs in the hot water switch had completely corroded, probably due to the steam in the machine from the leaking boiler gasket. After fiddling and experimenting with various sizes of springs I got the switch working again.

That's the restoration over, now for the interesting bits; The large white box contains a PCB, it has a power relay activated on or off by momentarily pressing the non latching on/off switch. There is also a 30 minute timer and possibly electrical suppression to limit arcing across the relay points. The upshot is that there is nothing there that would prevent the fitting of a PID to control brew temperature, the main ice cube type relay is easily bypassed to avoid irritating constant clicking when fired by the PID. Power draw when both boilers are on at once is 2250W, but that is only for a short while when first switched on. There is probably room for the PID and SSR in the case.

By far the most significant difference between this machine and the earlier type is that *this machine does not have an OPV*_*.*_ The needle on my portafilter pressure gauge holds at 4-6 bar for a few seconds than swings past its max reading of 11 bar (pump goes up to 14bar?). Do Kitchenaid think that their customers will not want to use ground coffee?

So this later version isn't as useful as the earlier version, the timer and lack of an OPV hamper its usefuness. The OPV from a Classic will fit but that still leaves the timer issue, which may or may not be fixable. I don't know how to tell the difference between them without taking the top off. The old one had a level warning float in the drip tray with a hole on the cover for it to poke though, this later one doesn't have these.


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## Norvin (Sep 10, 2014)

Having just read my last post I thought that i should clarify that the later Kitchenaid has an OPV on the steam boiler. What I meant to say was that the later Kitchenaid does not have an adjustable OPV to control the brew pressure. Even that may be wrong as if the steam boiler fill solenoid is open when the brew switch is on then the OPV will regulate the pressure in both boilers. I don't have that machine any more so I can't check any details but I'm pretty sure that it is adjustable.


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## tiger_stripes (Sep 12, 2013)

I've just finished restoring a 5KES2102, which is of the type that @Norvin mentioned in the last few posts here. It has the larger box type white PCB, and a single OPV. I wanted to confirm that it is indeed adjustable (from above), and will regulate brew pressure. The confusion is understandable, as the adjustable OPV is located on the steam boiler. My machine is now adjusted to 9.5 bar at the portafilter. As far as preventing problems with the steam boiler, I've remedied this by installing a switch in series with the steam boiler thermostat. This effectively turns off the steam boiler by opening the thermostat circuit (when it isn't needed as opposed to when it's at the temperature set by thermostat). Currently looking to fit a PID kit, and was wondering if anyone had experience fitting one on this particular model. @Norvindo you think the "ice cube type relay" could confuse the programming of a PID? I think the relay is wired as a "flipflop", so gives power alternatively to the brew boiler or steam boiler - but what part of the machine decides this? How do we bypass the relay (and the logic controlling the relay) and hand over control to the PID? Thanks!


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## Norvin (Sep 10, 2014)

tiger_stripes said:


> I've just finished restoring a 5KES2102, which is of the type that @Norvin mentioned in the last few posts here. It has the larger box type white PCB, and a single OPV. I wanted to confirm that it is indeed adjustable (from above), and will regulate brew pressure. The confusion is understandable, as the adjustable OPV is located on the steam boiler. My machine is now adjusted to 9.5 bar at the portafilter. As far as preventing problems with the steam boiler, I've remedied this by installing a switch in series with the steam boiler thermostat. This effectively turns off the steam boiler by opening the thermostat circuit (when it isn't needed as opposed to when it's at the temperature set by thermostat). Currently looking to fit a PID kit, and was wondering if anyone had experience fitting one on this particular model. @Norvindo you think the "ice cube type relay" could confuse the programming of a PID? I think the relay is wired as a "flipflop", so gives power alternatively to the brew boiler or steam boiler - but what part of the machine decides this? How do we bypass the relay (and the logic controlling the relay) and hand over control to the PID? Thanks!


 it's been a while since I had anything to do with a Kitchenaid but i will try to answer some points from memory.

I seem to remember that the ice cube relay is switched by the brew boiler circuit energising the relay coil. You can remove the relay completely by bridging the connections each set of points to the brew and steam boilers. If you do this, the max power draw will be higher when both circuits are on at the same time but it will still only be about 2100W (OK for 230v systems, not sure about 110v systems).

You should be able to PID the machine quite easily, the power pickup will be a little more tricky as the on/off button is only momentarily on (non latching) so the pickup point for the PID power will be from the switched power supply somewhere on or near the board in the white box. It will not confuse the PID. The timer is a nuisance but I managed to disable that by moving connections on the board. I think it involved taking off the connection to the board from the pump and using a bridging wire to provide a constant connection. Of course, you should only switch connections if you are confident working with circuits.

With the older style Kitchenaid there is room in the housing to fit the PID and relay but I don't think there's room in the later type due to the white box.


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