Vaillant ecotec diverter valve tear down/ experimental repair

I replaced the cartridge in the diverter valve, for my Vaillant ecoTEC, 3 times!!! it lasts for a while and starts to leak again!
I think the limescale on the shaft is quite abrasive, and wear's out the o-rings seals quite quickly.
I noticed it was possible to remove a retainer washer on the cartridge. Now I had access to the o-ring assembly. I decided to experiment to see if I can improve the seal assembly.
Disclaimer: This is only a experiment , and not intended to be a proper repair. And ment as educational and entertainment purposes only.

[@advancedboilertraining]

Interesting video!

[@MyProjectBoxChannel]

Mabe the double o-ring can be changed to 4 o-rings inside the driver valve cartridge. This might increase the service life.

[@mrpat2563]

I love experiments, you have a good logical thought process, love it. Yes mine has just started leaking today and came across your video, I'm thinking of just changing the cartridge. Yes the valve design is not good, I suppose it also down to the quality of the seals. Remember those early cars that use to leak oil from engine crank shaft seals! you don't usually see this anymore, quality drastically improved. I remember replacing one of these on my nissan back in the 90's the rubber had gone hard and started to crack. This oil seal also had a small coil wire spring around the circumference, so as the seal wore the gap would close up, thinking about this the engine valve stem seals also have a spring around them and these valve open and close hundreds of times a minute, so if something like this could be done it would make them more reliable. But something like this would be a redesign! Coming back to the boiler maybe you should lubricate this shaft once a year or maybe sooner, it should be very easy and quick to do as this shaft is visible when the boiler cover is removed. Should only take a few minutes and you don't need to drain anything. This might help extend the service life so worth a try. If the manufacturer really wanted to improve the reliability of this valve so it don't leak at all they could use the induction motor method like boiler pump Magnetic operation In which there is no phyical contact between rotor and the coil. Good luck with your repaires though I hope it lasts 👍

[@colintinker7778]

A handy Poundland USB charger case to put the bits in! I had a similar leaking issue with our gas combi boiler a few years ago. Dripping from the shaft. Found a viton seal that was an excellent fit. Put in a good dollop of molybdenum grease. Still going strong.

[@bythesea2784]

Just today I saw there was a leak and it was this particular diverter valve as an engineer doing electric motors many years ago so far I got a box of rubber o-rings I'm sure the size will be perfect to replace all of them and put everything back together keep up the good work oh hopefully see more of your videos

[@MyProjectBoxChannel]

If you find the right o-ring, it's definitely cheaper than a new diverter valve👍😉. If I remember correctly, there's space to put a few extra o-rings in (Just remove one of the spacers/packers). It should improve the sealing and longevity.

[@Drillmechanic]

@@MyProjectBoxChannel Friction resistance encreased after that adding more O-rings ! My solution is coating each O-ring by the electrical thermal shrinking isolation.

[@MyProjectBoxChannel]

@@Drillmechanic interesting 🤔 solution. Thanks for sharing

[@jtbtabimono]

Watched this with great interest. Let me share my story as well. My Vaillant Ecotec Pro28 started to have this leak. The leak is very minor, unlike others who have their casing flooded. The leak is not too bad when the heating is used regularly but now the weather gets better and valve is most of the time staying in hot water side, this seems to leak more. But even then, it leaves a dry mark as opposed to wet puddle. Mine is 12 years old and never had the diverter valve replaced before. The idiot plumber who fitted this, did not fit the inline magnetic filter. Because of this, it first of all buggered up the pressure sensor when the boiler was 8 years old and frequently threw the famous F75 error. When I drained the system to replace the pressure sensor, horrified to see the amount of gunk that came out. At the same time as replacing the pressure sensor, I've fitted an inline magnetic filter Fernox TF1 Omega and flushed the system thoroughly. The filter gets cleaned on regular basis. The inhibitor used until this point was Cura, which is own brand ones from the online plumbing store and I can clearly say it was rubbish. In other words, you could say the boiler was not very well protected until 8 years old. At this point, I've dosed up with Qualrad inhibitor. Now, I think it makes a difference where the boiler is situated. Mine is situated at the highest point in the house upstairs. First of all, the flue is through the roof so sucks in cleaner air than, say, boiler fitted on ground floor kitchen cupboard for instance. To prove this point, the amount of gunk that gets collected on the condensate trap is significantly less than those boilers at ground level. Second of all, though the inline magnetic filter does catch majority of debris, it does not catch non-magnetic debris and higher the boiler situated, it reduces the chance of debris getting up to a higher level. Ok the pump does churn things but after a while debris tend to settle at lower pipings of the house. As for your analysis regarding the lime scale causing the wear, don't know whether it makes any difference but I have a Fernox electrolytic scale reducer fitted before the water enters the boiler. So, even when filling the boiler, the water goes through the scale reducer. The electrolytic scale reducer does not eliminate lime scale, it just alters the characteristics so it does not cling to things. This was fitted with the boiler and I replaced it when it was 7 years old as I noticed in degraded performance. I live in Norfolk, which is one of the hardest water area within the UK. I will be replacing my current plastic diverter valve with a new brass one this weekend. Today I've drained the system and filled it up with Qualrad system cleanser. The system water that I drained wasn't too bad. I will run the system for about a day or so before draining and replacing the valve at the same time.

[@chesshooligan1282]

The brass diverter valve cartridge has a very nice design that makes it very easy to replace. Once installed, it can be removed without the need for special tools, and the replacement nipple only costs £7. However, it has a problem. The plastic circlip that keeps it in place deteriorates with the heat from the water. Mine lasted about 4 years before it crumbled. If that circlip had been manufactured with a heat-resistant plastic (nylon?), that brass diverter valve would be perfect. What a shame.

[@albeer49]

Большое спасибо за очень полезное видео.

[@dudekushie3762]

It’s that small amount of magnetite sediment that has got inside causing the failure. It nicks and grinds on the internal orings until they start to leak. 👍🏻

[@MyProjectBoxChannel]

It's abrasive and grinds down the o-ring seals. But won't the magnetic filter remove most of the magnetite particals?

[@dudekushie3762]

@@MyProjectBoxChannel I think the filter is supposed to help protect the boiler, but it won’t eliminate every single particle of sediment passing through. Eventually over time, bits get caught up in various components and is ultimately the cause of failure. I think it’s key to eliminate as much debris as possible before the install to maintain component longevity.

[@MyProjectBoxChannel]

I have seen your fit once system. It's a very clever solution for a recurring problem. I can't help thinking this is a inherit design failure. These diverter valves should be more more rugged and be able to cope with a bit of dirt in the system. My water seems spotlessly clean, and the magnetic cleaner as well. These failures are just all too common. Paddle type diverter valves don't suffer from the same problem.

[@mdede2000]

What system uses a paddle type diverter?

[@MyProjectBoxChannel]

@@mdede2000 I believe some Worcester Bosch boilers use the paddle type. But don't quote me on that I'm no expert 😂

[@jemajema5092]

Very very smart video

[@ilyaasoow]

It has been 11 months since you posted the video. Could you please update us on if it worked? Mine fails every two years. I always keep spare one at home, one just failed and i fitted new one, i am trying to buy new spare one now but the prices seem to have almost doubled. My next boiler is definitely going to be INTERGAS, this boiler has no diverter valve.

[@MyProjectBoxChannel]

It most definitely did work, but I did replace it with a new original cartridge, about a month later. I was just curious to see if the seal could be improved. The problem is you can't do these kinds of experiments permanently on a gas safe installation. There's no insurance liability for it. I have since sold the house and the boiler has been put back to standard, and has had a gas Safe inspection. There is a company that makes a replacement cartridge that you fit only once and it has a replaceable seal, which can be replaced without draining the boiler. buycombi.com/product/ef-pb/

[@majidhussain6142]

Have issue with mine ( it’s brass) brass valve or plastic doesn’t make difference.

[@MyProjectBoxChannel]

That makes sense, since the cartridge that leaks (o-rings) inside is the same.

[@mubarakshams5279]

I too have had to change this at least 3 times and think it's a product design fault and vaillant should recall. I honestly believe they should be sued. How can a part fail so many times and no one's raised an eyebrow?

[@MyProjectBoxChannel]

Agreed! And everybody just blames the water quality or inhibitor or something like that. My water was absolutely fine. Although I live in a very hard water area, the boilers should be designed to cope with that. The system was professionally cleaned, very thorough! Definitely a terribly bad diverter valve design.

[@chesshooligan1282]

I raised an eyebrow, but nothing happened.

[@pankajmorjaria6763]

For small part why do people have to purchase whole diverter valve and spend nearly 10% of the new boiler price? Cant they make something durable? Or they intentionally dont want to make durable and want to make money ?

[@tomhilditch3882]

Its your dirty Heating water. Take a look at VDI2035

[@MyProjectBoxChannel]

I don't think it's dirty water, the system was properly flushed and inhibitor put in. The magnetic cleaner is regularly inspected and spotless.

[@tomhilditch3882]

Your water is clearly dirty, the o-rings are breaking down the black mess from them shows this. The magnet will collect some ferrous metals not all. To much inhibitor can cause this fault too. If your having multiple failures get the water tested

[@MyProjectBoxChannel]

I will do that 😉

[@stevenjohnson6082]

you seem a really competent person but you need to be gas safe to work on boilers, youare also modifying the boiler which is a unknown you say that it is ment as educational and entertainment purposes only. but you are running this boiler

[@MyProjectBoxChannel]

Thanks for your concern. I have replaced the diverter valve seal cartridge back to an original part. The boiler has since been inspected by a gas safe engineer. I work as a maintenance engineer for a large oil company. I'm very familiar with large industrial gas boilers and various HVAC systems. Working on domestic boilers is child's play compared to the complexity of the systems that I normally have to work on. I believe If you are a component person, and you own it, you should be a loud to work on it. Not a big fan of the nanny state. That's how I learned electronics, by fixing stuff.

[@stevenjohnson6082]

@@MyProjectBoxChannel I'm Shaw you are a component person ,there are many people that think the same but are not component its the law and its there for safety i am gas safe and i see other engineers and think how did you pass you gas safe

[@MyProjectBoxChannel]

@@stevenjohnson6082 you've kind of taken the words out of my mouth. I wasn't going to say anything. I have seen some of the incompetent work of so-called gas safe engineers! Sometimes I feel like these accreditations are just a protection racket, in the name of safety, and lobbied by the government. I have seen it happen as a qualified electrician where somebody else has to sign off my work. Some of the best engineers that I've seen, and most knowledgeable people that I know, have no government accredited qualification. I'm sure there are some gas safe engineers that are excellent at their job(my fellow work colleague for example) and absolute professionals. I'm totally with Elon Musk, He would rather employ somebody he knows is good, then with lots of qualifications. So-called engineers and technicians these days are just part fitters. No body will replace that 1 pence resistor on a PCB, but just replace the £100 board. Or just replace the pump instead of changing the £2 O-ring or bearing. I was taught to repair stuff by my dad (a proper engineer) If we couldn't find the part we would make a replacement on the lathe. At school I was taught to change a plug my Self. Now days that's a electricians job?? It's the nanny state and I'm not having any of it.

[@yensabi]

Vaillant Ecotec diverter valves are a shit design , of all the different makes of boilers I repair these are the only ones that give major problems like this , the only way you have a chance is by fitting a good quality filter and drain and flush your system every year and put a good quality inhibited in the system

[@MyProjectBoxChannel]

I think you are right. Something isn't right with this diverter valve design. I have been told that the brass version is much better than the black plastic one.