Toilet tank slow to fill and whistling noise

xyz123

Hi, since the weekend our toilet tank has become very slow (5 minutes plus to fill the tank) and there is also now a whistling noise coming from it. It is not leaking just slow to fill. 

It is a non branded dual flush system. I am guessing the fill valve needs replacing but not 100% sure. Could there be any other things to replace?

Also how do I find matching one (short of trying to take existing one to a shop) Are they all standard and will fit in any toilet?

I haven't replaced one ever so asking these stupid questions. Will try to look on youtube on how to replace it.

Thanks 

ThisIsWeird

Could you lift the lid and take some photos of the gubbins? 

And does the supply pipe have an isolating valve on it so the water can be shut off for just that loo?

FreeBear

If you have a bottom entry cistern, I would recommend this fill valve - https://www.screwfix.com/p/flomasta-bottom-entry-fill-valve-1-2-/5527f - Very quiet in operation, and adjustable to suit most cisterns. I needed a smear of silicone sealant around the rubber seals..

CliveOfIndia

I've had exactly this problem on a couple of our toilets - in fact, I fixed the most recent one just yesterday.

It depends on the particular design, but on mine it was the inlet washer had split.  Here's a link to the type of thing for illustration: https://www.amazon.co.uk/SIAMP-Diaphragm-WASHER-Duravit-Twyford/dp/B00BG6C4N8/ref=asc_df_B00BG6C4N8/?tag=googshopuk-21&linkCode=df0&hvadid=232056160750&hvpos=&hvnetw=g&hvrand=11147723515480057096&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9041106&hvtargid=pla-421631097311&psc=1

As you can see, not exactly expensive, and very easy to fit.  If this is the problem with yours then it's a very cheap and easy DIY fix.

propertyrental

utube is your friend.

Loads of 'how to fix a cistern' vids there. You just need to identify what's in your cistern now and what replacement you want to put in (or what part/washer needs replacing).

Post photos here for advice.