Toilet keeps overflowing

Just had a new toilet installed but It keeps overflowing. Im guessing there is a part missing or that needs adjusting? Any advice would be greatly appreciated.

Asked by Nan on 31st Mar 2020
Expert Trade Answers
"Hi Nan,

Thank you for question and hope you are well.

An overflowing toilet can be the result of a few issues which i will list out below, but the majority of modern overflowing toilets after an install may be:-

•The fill valve hasn't been set to the right height, (the part which fills the toilet). If you look inside the cistern you should be able to see that there is a part of the fill that moves up and down. If you can adjust this you can control the maximum level of water.

The other issues may be:-

•Your flush seal isn't stopping water like it should. You can see if this is the case by simply by turning off the water supply to the toilet and see if the toilet continues to drain. Most modern flushes have a mechanism where you can hand turn so it locks and reseals. Hopefully this helps (remember to turn off the water to the toilet before attempting any work you feel confident in).

•Part failure. This will be after attempting both methods and still no joy, you'll need a competent plumber to replace or fix the parts.

Good luck

Ben Hornsey
Hornsey Plumbing and Heating Ltd"
Answered on 31st Mar 2020 - Member since Oct 2017 - report
"If its a brand new toilet, chances are it's the float valve that needs adjusting above the overflow height."
Answered on 31st Mar 2020 - Member since Jan 2020 - report
"The ball valve or fill valve as some call it will just need adjusting."
Answered on 31st Mar 2020 - Member since Dec 2019 - report
"just needs a slight adjustment, sometimes it can be a wee bit of sedement causing the washer not to seal, should take any plumber 5 mins to sort"
Answered on 31st Mar 2020 - Member since Feb 2020 - report
"The fill valve will need adjusting or is damaged. If everything is new it might just need checking to make sure the washer is sitting properly."
Answered on 31st Mar 2020 - Member since Nov 2019 - report
"Hi Nan
This could be the fill valve which is set too high and running down the overflow. Or like you say there could be a part missing. Could you not ask the person who installed it to re attend and take a look?
Kind regards
Answered on 31st Mar 2020 - Member since Apr 2019 - report
"The valve will need adjusting. Turn off the water and adjust the flow."
Answered on 8th Apr 2020 - Member since Jan 2020 - report
"The float valve needs adjusting,you need to call the plumber who installed it really!"
Answered on 31st Mar 2020 - Member since Dec 2019 - report
"Ball valve or fill valve needs adjusting inside cistern
Answered on 31st Mar 2020 - Member since May 2018 - report
"Without seeing the cistern

In my opinion it could be two things

No1 the float valve needs adjustment or something is blocking the valve
No2 it could be the syifon letting buy and needs attention
Answered on 31st Mar 2020 - Member since Mar 2019 - report
"Hi its possibly the toilet is blocked or if its not then the float on the flush mechanism maybe stuck or requires adjusting if it continues after this then the flush mechanism may need replacing. Cheers, Craig"
Answered on 31st Mar 2020 - Member since Dec 2019 - report
"Either the float valve /ballcock needs adjusting or the washer needs replacing."
Answered on 6th Apr 2020 - Member since Nov 2019 - report
"I think there may be 3 possibilities:

1 - Check if any part of the system is missing;

2 - It is necessary to adjust the level of the inlet valve;

3 - There is something that is blocking the system operation correctly"
Answered on 31st Mar 2020 - Member since Apr 2016 - report
"Either the fill valve is letting by (leaking) or the syphon is faulty.


Answered on 4th Apr 2020 - Member since Mar 2020 - report
"You should contact the installer as they have responsibilities to insure their work"
Answered on 3rd Apr 2020 - Member since Dec 2016 - report
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