The first phase of the descaling process is now completed, i.e. the heat-exchanger. I also posted on my blog regarding this. Next weekend it is time to descale the boiler. I used Cleancaf for the HX, but I am not quite sure if this is best solution for the boiler descaling - should I use citric acid instead?

Thanks again for all the help and support!

Br,
Teme

Teme wrote:I used Cleancaf for the HX, but I am not quite sure if this is best solution for the boiler descaling - should I use citric acid instead?

Yes, use citric acid unless you want the steam wand to blow bubbles for the next few weeks (Cleancaf has detergents in it). You can buy citric acid by the pound at brewer supply stores, or in a pinch, Jim suggested cheap "imitation" lemon juice since it's really citric acid in solution.

Boiler descaling completed. It was uneventful process with the only concern being a vacuum breaker that did initially not seem to be sealing properly after the descaling (some scale ended up on the valve, perhaps?). However, in connection to the boiler rinsing the vacuum breaker also started sealing well again.

Thanks again for all the help. Now that I have done this once I feel comfortable doing it on a regular basis going forward.

Br,
Teme

Well, apparently things did not go smoothly after all. I switched the Andreja on and went out to grab a bite to eat, hoping to get a nice shot of espresso upon my return. Before I left, the Andreja was heating up normally (as it had done earlier on in the day after the descaling). However, upon my return the machine was warm but no longer heating and the boiler was at zero pressure. The light indicating that the heating element is on is lit up and the machine receives power, but it is not heating up. I will open it up later to check if the hi-limit protection on the heating element has tripped but any tips on what could be wrong?:-(

Oh. I did get a cup of coffee - contingency procedures were initiated and the Pavoni served me well

Br,
Teme

Hi Teme,

Let's hope you do not have the same problem I had earlier this year. I descaled the boiler in my Expobar back in the Spring. After descaling, the heating element literally split open (see below photos). There was just enough electricity going into the element to warm the water.

I don't know if the descaling caused this, or merely hastened it. The techician that repaired my machine said he had never seen a heating element split and uncoil like that. He thought it was a manufacturing defect, but admitted that was just a guess.

As you might guess, my only solution was to replace the element.









Good luck,

Jeremy

Hi Jeremy,

I opened up the Andreja and fortunately it seems that it was only the hi-limit switch that had tripped. I reset it and the Andreja is up and running again. I still wonder what actually made it trip? The timing indicates that it is connected to the descaling. I will need to keep an eye on the machine for any abnormalities. For now, as a precaution, I am also taking out the timer it is connected to...

Br,
Teme

Teme wrote:I will open it up later to check if the hi-limit protection on the heating element has tripped but any tips on what could be wrong?:-(

Emptying and refilling the boiler can cause this if the heater is not locked out when the autofill is running (the Giemme is supposed to do this, but mine doesn't). The heater is running in air and could trip the safety stat. especially if the refill is slowed. I blew my thermal link after flushing my boiler and replacing the hose end softener with one that was nearly jammed.

I descaled my Isomac last weekend. I had the same issue with the vacuum breaker valve but it resolved itself. The entire process was quite easy. The green water was interesting (cleaned out the oxidation from the brass). I got quite a bit of particulate, fine sand like sediment. I was surprised how much smoother it works. I must have had a little deposit in the lever, the annoying squeeeeek, I got when I lowered my E61 lever is now resolved, works like new.

another_jim wrote:Emptying and refilling the boiler can cause this if the heater is not locked out when the autofill is running (the Giemme is supposed to do this, but mine doesn't). The heater is running in air and could trip the safety stat. especially if the refill is slowed. I blew my thermal link after flushing my boiler and replacing the hose end softener with one that was nearly jammed.

This makes sense. However, the safety was not tripped during the refills, if was tripped afterwards when the boiler was at the normal level and the machine was heating up.

Nevertheless, after resetting the switch the machine has been running faultlessly. Next time I descale, I will lift off the water reservoir so that the water level sensor thinks that the tank is low on water and hence disables the heating element during the refill, while still allowing the pump to run (at least in the Andreja). To heat up for another boiler drain, I will then just lift the reservoir back on.

cannonfodder wrote:I descaled my Isomac last weekend. I had the same issue with the vacuum breaker valve but it resolved itself. The entire process was quite easy. The green water was interesting (cleaned out the oxidation from the brass). I got quite a bit of particulate, fine sand like sediment. I was surprised how much smoother it works. I must have had a little deposit in the lever, the annoying squeeeeek, I got when I lowered my E61 lever is now resolved, works like new.

Yes, it was surprisingly easy with Jim's clear instructions. I did not get much sediment at all - I take this to be a good sign (i.e. not much scale buildup).

Br,
Teme

I was glad to get a little particulate in the water, that way I know I did it correctly. I use filtered water so what I refer to as 'quite a bit' may be next to nothing on someone else's machine. It is the first time this machine has been descaled (about 11 months old).

I was going to cut the water level sensor wire and install a momentary push button switch under the drip tray but I was not sure if it was NO or NC while I was at the store. I just pulled the lead off the sensor, opened my steam wand valve and let it fill until it ran out of the wand. Then gave it another 15 seconds or so. I let it heat a bit, then turned it all off and let it sit. Then repeated the process two more times. Over half a day.

Ironically, I think the hardest part is flushing out the descale liquid. I ran two reservoirs of clean water through the boiler and HX line. I kept flushing until the water was nice and clear, then a couple of additional flushes for good measure.