Recent: Will I need to replace my garden tap?

Mend > Home Heating Systems

Mend Ariston SX20 MFFICE Boiler Heating Radiator

problems with my Ariston eurocombi boiler sx20 mffice?

1)When I fill my boiler to just over 1 and a half bars and then switch the heating on the needle goes right to the top of 3 bars and discharges water out of the overflow pipe. When I switch the boiler off the needle goes well below 1 bar and I have to keep topping the water up.

2) I have also been advised that my hot water tap is running through my boiler?

3) When i use the hot water one of my radiator seems to get hot ?

I have checked for leaks and air blocks in all the radiators and they all seem ok. I have been advised that i need to replace the diverter vaulve and have been quoted £160.

Can someone please advise me.
many thanks Hash

Hashim
November 2006
No hot water but heatin works. Any idea

lee
July 2013
hoa do I repressurise it.I don't know which screw on the pipes underneath I turn to do this.Is it the main water tap on far left?

jane
December 2009
by the by, the boiler will not start unless the pressure is over half a bar.

engdes
May 2009
THE MOST COMMON PROBLEM WITH THIS DESIGN IS THE DIVERTER VALVE DIAPHRAM. THIS GOES FAULTY EVERY 2-3 YEARS AS THE RUBBER IS UNDER CONSTANT STRESS. THE SECOND MOST COMMON FAULT IS THE PUMP WHICH YOU CAN OFTEN GET REWORKING BY HITTING IT WITH THE WOODEN HANDLE OF A HAMMER. It cost £10 to fix the diaphram, if you know what you are doing.

engdes
May 2009
i have an ariston sx20 mffice, does anyone know how to relight the pilot light?..i have lost my manual and the instructions on the boiler were ripped off ..not sure if it was my children years ago..i not long ago had a new board put in ..after some months it wouldnt start up ..i pushed in the reset underneath the boiler and it started fine ..now its happened again and pushing the reset underneath does nothing and it looks like no pilot is lit, i think it needs relighting but i dont know how

david
February 2009
have a ariston sx20 mffice. no c/heating or hot water. the pilot light is off, although the warning light does not appear to be on. the pressure is at 0.5 bars. i know nothing about boilers, but my rental agency didnt fix it before christmas and are now closed for two weeks. and im in scotland and v.v cold.

i have tried following the instructions on the panel to relight the pilot but nothing is happening. incidentally i do not have an instruction manual! is there anything relatively simple i can do to try and fix?

how much would it cost approx to get it looked at? i've never had to deal with plumbers before!

btw im not blonde, but feel like it!x

sarah
December 2008
Your problem with the pressure is caused by a lack of air in your expansion vessel.The vessel is behind the boiler (nomally red).You need to remove the dust cap(same as car tyre)from the to of it and pump it up to 0.5 bar but you will need to remove any water pressure from the boiler.
The radiators heating when running water does sound like a faulty diverter.An origional ariston would probly cost around £120.00 and it's a bit of a sod to change,so price sounds about right.
Hope this helps

Pete 100% Heating ,Bristol 01454854067
November 2006

Related Questions ...

Mend radiator thermostat heating
2

One radiator in a bedroom is always cold?

One radiator in a bedroom is always cold. It used to work fine. I have tested the thermostatic value and the... [Read more]
Mend boiler heating pressure
2

what is wrong?

After topping up our baxi boiler with water from the loop to bring it to the right gauge level which i do now ... [Read more]
Mend boiler heating thermostat
1

combi oil Worcester greenstar heatslave 12/18 switches off?

I have a internal combi oil Worcester greenstar heatslave 12/18 Its has a built programmer and Hot water t... [Read more]
Mend boiler fault engineers
1

home heating systems?

I have an 12 yr old Highflow Electronic system, which is working perfectly for hot water. However the heating ... [Read more]
Mend ravenheat white boiler
2

What is wrong with my ravenheat white star combination boiler,?

I have a ravenheat white star combination boiler,it suddenly decided not to turn off,its on all the time,I hav... [Read more]
Mend boiler pressure heating
1

Ferolli Optimax HE Plus 25 S Loosing pressure randomly?

This is a very strange problem that has my plumber friend very confused. When the boiler is on, the pressure ... [Read more]
Mend boiler heating pressure
3

Why is the pressure on my Ariston boiler rising to nearly 4 Bar?

Hi Can anyone please advise me on why my Ariston Eurcombi A/27 MFFI pressure is rising from just over 1 Bar... [Read more]
Mend central heating radiator boiler
1

Central heating radiator doesn't gets hot sometimes and sometimes does?

I have a potterton kingfisher cf 50 boiler.My up stairs ch rads is fine but down stairs one of them is warm nd... [Read more]
Mend boiler leak heating system
1

Radiator problem ?

after a recent leak in my central heating system which is now fixed, i've refilled the radiators and fired the... [Read more]
Mend boiler heating worcester
1

Worcester green star junior 24i?

My husband has just removed a radiator. The bar pressure was running low before he removed it and so he incre... [Read more]
Mend boiler pressure loss central heating
1

My Ariston Combi A boiler keeps losing pressure from Central heating loop?

Heating loop pressure drops to the red line twice a day. Cannot find any leaks from any of radiator and no lea... [Read more]
Mend heating boiler pipework
2

worcester bosch 240?

my boiler was drained from the small tap underneath the boiler while we had a new radiator and pipe work fitte... [Read more]
Mend boiler radiator heating
1

drain bedroom radiator?

heatline s24/s30 combination boiler need to remove inlet valve from radiator/pipe in the bedroom not certa... [Read more]
Mend boiler radiator pressure
1

how can i correct central heating pressure?

i have one radiator which is half way warm and half cold so i decided to bleed. i switched off the boiler and ... [Read more]
Mend boiler leak pressure
1

valient turbomax 242eh central heating will not operate once it reaches tem?

242 eh installed with 3 rads the boiler works fine in hot water when in ch and hot water mode ch reaches temp ... [Read more]

How to mend ...

Find out how to mend just about anything howtomendit.com for free repair help, information and advice.
Mend Home Heating Systems ...