# Cherub odd behaviour with alarm?



## cplev (Mar 22, 2011)

Hi all

I have a Cherub bought secondhand, used everyday and reasonably regularly cleaned and descaled. Water used is filtered.

Recently it has started to cut out with a beeping, usually in the mornings when warming up.

The pump runs for a while filling the boiler I guess and then after some time cuts out leaving a quiet beeping from the machine.

Switching off and then on after a few seconds seems to clear this and then usually on the second or third reboot it seems ok.

It can however also do this after pulling water from the hot water valve for tea, and often cuts out when pump is refilling the boiler.

Is this a false low water alarm, or a boiler filling timeout alarm? Is the pump not delivering enough water?

The pressure seems a little low at the head and overtamping will reduce flow to an occasional drip, but I don't have a pressure gauge to check this.

I am perfectly ok with replacing parts and making adjustments etc, but my knowledge about the machine is very limited - I removed and checked pipework near the pump for scale following these symptoms, thinking perhaps the pump was blocked by scale fragments following descaling, but all the pipework seems clean enough. I also adjusted the anti-spill valve at the bottom of the water tank(black plastic screw) so that it opens a little more when the tank is replaced. This also made no apparent difference.

Should I try a new pump? Or what should I do next? Anything I should check?

This is my first machine up from a Classic and it was great to be able to pull 3 or 4 shots and steam milk without delay, I hope I can fix this problem!

Any help much appreciated.

Chris


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## Jon (Dec 3, 2010)

I'm guessing it's scale on the sensor. That would also explain the head issue. Expect the head is scaled.


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