Timo -

Have you physically checked your water level? Have you inspected the condition of the probe?

See here: Possible Quickmill Anita temperature problem

Hello Eric,

Thank you for your response. I will check the condition of the probe and the water level but I have stupid question though.

I took a look at Chris Coffee's FAQ that told the following about replacing a liquid level sensor probe.

"Step one remove your old sensor probe by loosening the boiler nut. NOT THE PROBE NUT". To check the condition of the sensor I can probably just loosen the probe nut and pull out the teflon sleeve and the probe? What is the point in removing the boiler nut when replacing the sensor. Isn't it enough to replace just the sleeve and the probe?

Timo

No, you cannot EASILY remove the teflon sleeve. The reason is that the tightening of the uppermost nut (what I would call the gland nut) compresses the teflon a little and, over time, it takes the shape of the internal machine threads it is being compressed against.

Item 4 in the pic is what you want to remove after first slightly loosening item 2. Item 4 is a 1/8" BSPP male to 1/8" BSPP female adaptor that screws into ANOTHER adaptor in the boiler.

Simply loosening item 2 (the gland nut) and lifting out the probe MAY tear up the teflon due to scale buildup on the probe shaft. Yes, it would be rare, but you don't want to be the unlucky one.

It is very easy to determine if your probe is faulty or not. Simply pull the wire off the probe, the pump should kick in and call for water with in a couple of seconds. Then simply touch the wire from the probe to the top of the boiler it should stop. If that is what it does that tells you the control in the board is working fine. If you have a problem that the pump is not kicking in to call for water when it should you more than likely have a crack in the Teflon sleeve which creating a constant ground. If the probe is sensing ground it won't call for water. Also keep in mind that expansion and contraction happens when the water in your boiler is heated and cooled. If your boiler is full, you turn the machine off the water contracts. You turn the machine on, it may call for water to bring the level up to the probe. After that water heats it will expand slightly above the bottom of the probe. If you want to avoid wet steam open your hot water tap after your machine stops heating and pull water until it calls for water. Now after it comes back up to pressure it is no long slightly over filled.

Thanks a lot Eric and Chris,

It seems that it is time to order a new liquid level sensor probe. I pulled the wire off the probe after taking 200ml of water from the hot water tap. The pump started. So there is nothing wrong in the control board.

. . .it is time to order a new liquid level sensor probe

And, while you're at it, a replacement teflon sleeve and camera to take a pic of what you find when you do the autopsy. For sure, the operation of the autofill circuit is as Chris described but it would be interesting to know what the resistance of your probe circuit is (machine unplugged) when the water level is "proper". For example, mine is 835,000 ohms at operating temperature measured between the probe and the ground connection on the Gicar box.