Inside a float (Torbeck) toilet fill valve. How they work and fail.

I made this video to help with understanding common fill valve (water inlet) types, especially the Torbeck, which was made by Opella but now owned by Fluidmaster. I have seen many videos where they show the, "failing to fill issue," but because they don't understand how it works, they miss a really simple and easy fix. The Torbeck is often viewed with suspicion as it's made of plastic and looks cheap and flimsy. I too was originally hostile to this design. Time has proven that this hostility was totally unfounded and it has proved a very reliable and durable valve. The simplicity of design is genius and I now understand why this valve was so widely used and fitted. I have seen these valves in use in a hard water area, working for over 15 years without any issues.
Content chapters
0:00 Introduction
1:19 Disassembly of a standard bottom entry float valve for comparison
2:31 Explanation of standard valve with schematic
4:31 Disassembly of the Torbeck side entry float valve
6:12 Workings of the Torbeck with schematic
9:58 Comparison of features regarding back siphonage
11:01 Reassembly of Torbeck valve
12:54 Why valve can cause water hammer
13:40 Using a supplied restrictor to mitigate water hammer
13:56 Demo, The effects of water flow with the different restrictors
15:06 Common faults (failing to fill demo due to torn diaphragm)
16:07 Common faults (overfilling and failing to shut off)
16:45 Installation tips, introduction
17:20 Installation tips, fibre washers
18:57 Installation tips, rubber o-rings
20:51 Installation tips, silicon washers
21:21 Installation tips, avoiding cross threading
In my video the unrestricted flow was : 12.9 ltrs per minute
with low pressure restrictor it was: 5.5 ltrs per minute, meaning a 42.6% of the unrestricted flow
calc used ( 5.5/12.9 = 42.6% of unrestricted )
with high pressure restrictor it was 2.04 ltrs per minute, meaning a 15.8% of the unrestricted flow
calc used ( 2.04/12.9 = 15.8% 0f unrestricted )
These figures are taken from the practical which can be seen in • A practical demo of a ...
Replacing the diaphragm costs less than £2.00 (in 2021)and can be performed in an awkward location in less than 2 minutes, rather than the usual fitting of a whole new replacement valve. Fitting a replacement could take between 20 minutes to an hour. The plastic (hand tight) nuts are an advantage in hard water areas. Plastic naturally resists scale adhesion to its surface. Consequently, adhered scale is easily removed mechanically or with weak acid, as and when it is necessary. Brass bodied valves can be a liability in hard water areas, as they can easily seize with scale and corrosion.
In fact, something I didn't say in this video was: since nearly all the valve control components are under the removable blue cap. If it goes wrong you can just replace the entire mechanism without needing to remove the body of the valve by essentially using a donor valve. This would mean replacement would be one of the quickest, simplest and cheapest on the market
If the content was useful to you please subscribe: / @robertwilliams8032
Editor used was: the excellent free version of Black Magic's Davinci resolve 17.
Camera: is unworthy of a mention
Lighting: Fositan Studio Kit

[@geoffvincent7308]

Excellent! Just what I needed to understand how a Torbeck valve works, and why mine had failed. Also why when it failed it stopped filling, which seems counterintuitive. Torn diaphragm!

[@robertwilliams8032]

Great to hear!

[@EamonnKee]

Well done. Well explained! Concise. All useful information. Thanks!

[@robertwilliams8032]

Glad you enjoyed it!

[@ericrogerhall]

Excellent explanation... just what I needed. Many thanks Robert.

[@robertwilliams8032]

Thanks for the kind comment.

[@gavin18787]

Just what I was after. Fitted one of these and it was bugging me how it worked. Now I know! Was sceptical as first as the first couple of fills it didn't shut off. Seems fine now so must have just been bedding in

[@robertwilliams8032]

Glad you found it useful.

[@nemocap2958]

Very detailed! Finally!

[@robertwilliams8032]

Glad you liked it.

[@tsb3093]

One issue I had is that on an older (about 12 years old) Torbeck bottom entry filling valve when a tap was opened elsewhere in the system, the drop in pressure caused the filling valve in an already full cistern to reopen. I’ve now replaced with a new Torbeck valve and monitoring it. I also have Opelka Torbeck symphony valves which are rubbish and continuously leak to the toilet bowl. I see they have been discontinued.

[@davidupton3186]

Very informative video. Thank you for uploading.

[@robertwilliams8032]

Glad it was helpful to you. Thank you for your comment.

[@alkimefe160]

Great explanation sir. Thanks.

[@robertwilliams8032]

You're welcome

[@owenjoseph6097]

Great knowledge! Thanks for posting this excellent video

[@robertwilliams8032]

Thanks for your kind words and I'm glad it was well received by you

[@ebainton]

Really helpful video! I get why it might not fill at all, and I get why it might hammer as it shuts off. But ours is dripping once every 5 secs, and I can't think why it's doing that - diaphragm is all neat and tidy, and it's only a year old. Is it that 1/4" bung maybe? Any ideas welcome... Thanks!

[@robertwilliams8032]

Hi Edward, Thank you for your comment. Hopefully the video will allow you to see the only two mating surfaces of the valve. The first being the diaphragm and the second the bung on the pilot valve/float valve. If the drip is coming from the main output then it is the internal diaphragm. If it is coming from the front then it is the bung. Check for either perished material or debris lodged in the seat causing the slow leak. If you have the torbeck you can see that this is really easy to disassemble for closer inspection. The diaphragm is used as part of the sealing mechanism for the clamp so if it is leaking through the thread then it is the diaphragm but this could mean it is just needs to be tightened (no more than hand tight). A replacement diaphragm is very easy to find but the bung might be more of a challenge. If this is a UK fitting then I believe they are tested for over 100000 lifetime operations, so I would be surprised if there was a material defect so soon and the manufacturer may be inclined to supply a replacement for free.

[@ebainton]

@@robertwilliams8032 Brill, thank you. I'll try tightening it up a wee bit. (It's the diaphragm, by what you've described. And I should have been able to reaslise that from the vid...)

[@TheRainHarvester]

Great explanation!!

[@robertwilliams8032]

Glad this was of some help to you.

[@jimmyqing]

Great video.. very informative.. thank you..

[@robertwilliams8032]

Glad it was helpful!

[@huwlewis1083]

Great video although one of the main common faults (on screefix) which I also experienced is dripping. I fitted a new valve and according to the instructions dripping should be experienced for up to 12 seconds, mine never stopped so I replaced it and the aecond one was exactly the same, both brand new units from Screwfix, nothing visibly wrong with either unit.

[@robertwilliams8032]

This is fundamentally the same technology as used in washing machines' inlet valves, so it is interesting you had so many problrms. Do you have very high or low water pressure? This video shows a practical demostration showing the valve in operation kzbin.info/www/bejne/o2LPqWyOmKqdr6c

[@huwlewis1083]

@@robertwilliams8032 I left the second unit on, as the drip was only slight, and captured the water loss in a container from the overflow. After about a week or so it just stopped completely and has been fine since. I would say the water pressure is normal.

[@TheRainHarvester]

15:15 should it say, "if the rate of deflation is less than inflation, then it will never TURN ON"? (Instead of , "it will never shut down".)

[@TheRainHarvester]

Or equivalently, "if the rate of deflation is HIGHER than inflation, then it will not shut down".

[@robertwilliams8032]

Yes you are totally correct, I fumbled that part of the explanation, which I hope was somewhat recovered by the following demonstration.

[@TheRainHarvester]

@@robertwilliams8032 you still have one of the best demonstrations\ explanations on the web! Thanks!

[@davy999]

Excellent. A bit long but full of useful tips

[@robertwilliams8032]

Thanks for your comment, I'm glad you enjoyed it and found it of value.

[@An.Individual]

Nice video.

[@robertwilliams8032]

Glad you enjoyed it

[@Paulthepsych]

Unless somehow I missed it, you did not explain the function of the clear plastic tube/ flimsy plastic bag. Mine split and I had water pouring out into the cistern. It's clear when these valves go they go dramatically!!

[@robertwilliams8032]

Thanks @Paulthepsych for the question. I did mention the operation of the pipe briefly, to stop the dripping plopping noise often heard at the tail end of the filling operation. It does two jobs 1. it allows the water to follow a path and easily break the surface tension so the noise caused by sudden air displacement is minimised. 2. if there is backsiphonage the pipe will collapse in on itself sealing the reverse passage of water. being made with an air gap is belt and braces overkill. Typical of British design.

[@robertwilliams8032]

Further to my previous reply, a split or hole in the plastic tube will not effect its operation, in fact it would actually make it less likely to backsiphon. Effectively it being an additional air gap. In fact you can achieve the same results with a piece of string or mesh tube. More recently the manufacturers have stopped fitting this tube altogether probably as a cost cutting measure.

[@nnmmnmmnmnnm]

Yay; fixed my toilet!

[@robertwilliams8032]

Yay, excellent work.

[@bobflyman]

Pile of junk. Mine wouldn't shut down properly, had a leak, serious fast drip. I checked the valve, no debris etc. I got a refund.😢. Fitted Skylo. No leak and cheaper.

[@robertwilliams8032]

Hi bobflyman thank you for your comment. Since the company Fluidmaster bought the Torbeck product line from Opella , the price has gone up sharply, especially when compared to its in-house cousin, the 400a. The 400a has a much more elaborate design with many more moving parts but for some reason it's cheaper. The valve while in operation only has two moving parts 3 if you include the backflow flap as shown in my video. Would you care to share which part of the valve you saw was leaking as it might help someone else who has the same problem but may not be willing to spend money or time replacing it with a new valve?