Ariston MicroCombi 23 MFFi Issue Heating and DHW

Joined
7 Dec 2019
Messages
1
Reaction score
0
Country
United Kingdom
Hi all,
I have an issue with my Ariston MicroCombi 23 MFFi boiler.

We lost hot water a few days ago, some diagnostics showed that the DHW temperature sensor / thermister was looking bad (low ohm reading), since this issue occurred every time we use the hot water the central heating wont fire up.

Thermister on the DHW side has been replaced and we have hot water again but the other problem still exists.

Goes like this:
  • Start / reset boiler
  • Heating (burner plate) comes on and goes off all good.
  • Hot water comes on and off no problem.
  • Whenever hot water is used and turned off the burner goes off - even if heating is on - pressure stays consistent.
  • If heating is on when hot water is turned on boiler pressure drops by approx 0.25-0.5 bar and the burner plate visibly reduces flame slightly.
  • Once the hot water goes off the burner also goes off so the heating goes off.
  • Turning heating on and off via the thermostat does not reignite the burner, although pump comes on and pressure increases.
  • After 5-6 mins the boiler resets itself and the heating will work again.
  • Failing this its a manual restart of the boiler.
  • Use the hot water and we are back to no heating and waiting 5-6 mins or a boiler reset.
  • Hot water will continue to work though.

Any ideas?
S
 
Sponsored Links

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.


Are you a trade or supplier? You can create your listing free at DIYnot Local

 
Back
Top