Ariston Microgenus 24 HE MFFI Help

[loganberrry]

We've just moved into a new apartment which has a Ariston Microgenus 24 HE MFFI Boiler.

The boiler works fine, in the sense of heating water, however there are 2 issues with it.

1) the timer dial which dictates when the boiler goes on and off does not work (Not a huge issue)
2) There is no way to segregate Hot Water from Central Heating - when we switch the boiler on, its heats water and once it reaches around 45 Degrees it switches the central heating on as well - this is a pain as it means we have to constantly turn the boiler on and off every time we want a little hot water, otherwise we end up with a furnance.

Does the 2nd issue sound like a broken Diverter valve, and if so, how easy is it to replace this valve.

Any help greatly appreciated!

 

[Agile]

I may not understand what you are trying to say!

Its a combi and so it always can provide DHW. Thats how they work.

It sounds as if you mean that its jammed with CH on all the time.

This may be a stuck DHW flow switch. You could check by removing one wire from it if you can do that safely.

Tony

 

[loganberrry]

Hi Tony

Sorry for not explaining properly!

The issue is that there is a separate dial for Hot Water and for Heating - so that I could turn the boiler on and get hot water in the kitchen, but the central heating would remain off, or the other way around and have the heating on but no hot water in the taps.

What happens is that the dial for Central heating is non-responsive. So when I switch on the Hot Water Dail to maximum and the Central Heating to Zero, the Central heating still comes on, so it looks like the one dial is controlling both outlets.

I thought it may have been the diverter valve being faulty - but not the savviest with boilers.

Thanks!
Ryan

 

[Agile]

That adds weight to my suggestion that the DHW flow switch is stuck on.

Tony

 

[plumbnuts]

The dials to which you refer are thermostats - one for the temperature of the hot water and the other for the temp of the heating. You should not be controlling the boiler by these dials. On the top right of the time clock there is a small sliding switch marked I - (Clock) - 0 What is this set to and do you have a room thermostat/programmer?
Steve

 

[loubrighton]

Hi
We seem to have a similar problem with our Ariston Microgenus 24.
It has been working fine delivering hot water all summer. But having switched the central heating on a couple of weeks ago, it seems that whenever we draw hot water, the radiators come on, even if they are programmed by the timer to be off.
We also find that the hot water is no longer getting as hot as it was before.
Does this again suggest a faulty DHW flow switch?
Many thanks in advance for any thoughts.

 

[3142ron]

Hi I have exactly to same problem with my "ARISTON MICRO GENEOUS
23 MFF1" No. 535210. Turn on Hot water & "rads heat up". I tried adjusting
temperature settings on boiler control knobs to "Zero" for > rads & hot water and
still when running "hot water" "water temp still hot" & "rads heat up". Any suggestions welcome??
many thanks

Ron

 

[Agile]

Both the last two posters should have started their own thread as that gets more comments.

Both seem to have a faulty or leaking diverter valve. Thats quite common on a dirty system.

Tony Glazier

 

[GodKnows]

Hi Public,

Some of these have a "comfort" button or "Eco.". This is on the left hand side of the panel. Either blue or green dial. Comfort setting keeps the DHW at a warm temperature in preparation for a draw off. Wasting some gas as well

Turn it off, if you like...