Ariston/Grasslin Boiler Timer Help!

1 Feb 2006
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United Kingdom

I'm hoping someone can help me.

I have an Ariston Micro Genius boiler that has recently had the pump replaced. When the repair man was replacing the pump he managed to splash the timer switch with water and break the LCD display.

The switch now works as an on/off button but the LCD display is ruined so I cannot program it to come at certain times of day etc.

The repairman has long since gone and I am trying to locate a replacement part. I ordered a replacement part from RS components as the one on their website looked identical, however when it arrived the connections on the back were entirely different (3 wires instead of a 3 pin connecter and a battery like my existing part)

The manufacturer is Grasslin and the front of the timer looks like this


The connector on the back of mine looks like this

Can anyone help me find the same part or one that does the same job and will fit?

I have contacted Grasslin UK who haven't been particularly helpful and am running out of options.

Thanks for any help.

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I'm just guessing its a 27 mffi in which case if the serial number is between 2320219000000 and 2320021400002 then the manufacturer part number is: 706348

If its a higher serial then the part number is : 999600 list the later part.
Thanks!!! - I'll check the manual tonight for my boiler mode number.

I assume it's classed as an Ariston part (rather than Grasslin) in that case?


YEs, Grasslin is just the manufacturer of the programmer

I might have one lying around, but I won't have a chance to look until at least next week
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Does anyone possibly have a manual for the timer pictured above.
Trying to set the timer but is turning out to be a major mission.
would be great if someone could post a pdf on the net


Probably too late to help but I just found this:

which is a pdf of the user manual fo the a/27... programming guide begins on page 10.

Good luck,


(oh and by the way i flooded my own timer - without being a plumber - while swopping the diverter valve and not noticing that I had to transfer the blanking plug below the microswitch. Spectacular.)

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