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C-Tec Miracle seal for leaks. Anyone used it?

If it's a small leak on a straight run of pipe, the fernox may stop it. But if it's on a joint, it may not completely seal it. I've seen what the Fernox stuff does, it weeps out the hole and dries into a hardish glue on exposure to air. Bit like pva glue when it hardens. But if it's on a joint, the glue hardens, and may not deal with expansion and contraction. Fingers crossed for you.
 
I've a load of LSX in the shed somewhere which I offered to Mike FOC but there's no way I'd be putting that into a heating system with a brand new boiler.

Mike give Valliant tech support a call and ask them if they recommend you using leak sealer, I'm willing to bet that they'll tell you that you'll void the boiler warranty by using it as said above it goes rock solid and that will only end up blocking the heat exchanger.

0844 693 3133

0344 693 3133
 
got to agree with a lot of the other posters-your heating engineers is offering a sub optimal service and possibly taking advantage of your laidback nature. I would consider getting another engineer out from the boiler manufacturer and giving your trusted guy his papers-if he can't sort out the problem when you need him(depths of winter) what use is he?. i bet he wasn't slow taking the 4k
 
Mike give Valliant tech support a call and ask them if they recommend you using leak sealer, I'm willing to bet that they'll tell you that you'll void the boiler warranty by using it as said above it goes rock solid and that will only end up blocking the heat exchanger.

Tony, I'm loath to create a problem here by contacting Vaillant, as the boiler is under a long guarantee as registered by my old (and current CP12) plumber. After all, sealant has been used so the die is cast, as it were. Should anything happen to the boiler, he'd activate the guarantee repair regardless (unless he totally retires of course).

It's a waiting and monitoring game, as no major alternative solutions can be even thought about until late spring.

If it's a small leak on a straight run of pipe, the fernox may stop it. But if it's on a joint, it may not completely seal it. I've seen what the Fernox stuff does, it weeps out the hole and dries into a hardish glue on exposure to air. Bit like pva glue when it hardens. But if it's on a joint, the glue hardens, and may not deal with expansion and contraction. .

I rather think that it's a joint, as expansion and contraction from higher that previously seen temp's would, i.m.o., be unlikely to burst a pipe run. Obv. guesswork, but the water temp. went from 3.5 max out of 5 on the v. old Potterton to 75 degrees on this one. I deliberately never ran the old one hard, which may be why it lasted 35 odd years (21 with me).

How much air there is around those underground joints for the sealant to work is anybody's guess.
 
Tony, I'm loath to create a problem here by contacting Vaillant, as the boiler is under a long guarantee as registered by my old (and current CP12) plumber. After all, sealant has been used so the die is cast, as it were. Should anything happen to the boiler, he'd activate the guarantee repair regardless (unless he totally retires of course).

Fernox should be pretty safe. Very well known brand. I Googled and, for example, Worcester say Fernox F4 is fine to use https://twitter.com/HeatingYourHome/status/1069942951814594560

Might be wise to wary about any unusual/strong German sealer. Though Vaillant is German, of course, so unusual here could be well known in Germany.
 
Is that how they work? When they come in contact with air? Clever.
Fernox replied to question "is the repair permanent?" with "Fernox F4 Leak Sealer can be used as a permanent repair assuming air contact at the failure site. Please note if the system is drained for any reason the F4 would need to be reapplied".
 
Mike if the heat exchanger fails or becomes blocked Valliant's engineer will test the water in the heating system then you'll know if they don't recommend the leak sealer or not.

All of the boiler manufacturer's engineers test the water quality in heating systems as a matter of course these days even if they are only doing a non-leak repair/inspection ie changing a fan for example.

Some manufacturers use water quality as a get out of warranties no idea about Valliant though, their boilers are few and far between up here but I do know that Baxi/Potterton, Ideal, Worcester Bosch and Vokera all test the water quality in the heating system when they attend for a warranty repair.
 
Fernox replied to question "is the repair permanent?" with "Fernox F4 Leak Sealer can be used as a permanent repair assuming air contact at the failure site. Please note if the system is drained for any reason the F4 would need to be reapplied".

Personally there's no way that I'd use any leak sealer on a heating system with a practically brand new boiler, especially one that costs about £1400.
 
All of the boiler manufacturer's engineers test the water quality in heating systems as a matter of course these days even if they are only doing a non-leak repair/inspection ie changing a fan for example.

Next CP12 (sorry, Gas Safe) inspection will be next November, Tony, when the Magnaclean filter will be inspected/cleaned. Didn't know about the water quality check, though it's my plumber/installer who used it, so the onus, as far as I can see, is on him and effectively on the Vaillant agent who registered it. Anyway, Hobson's choice here; sth had to be done, temporary or not.

Third day of monitoring header tank/ingress/leak etc. in conjunction with the flow temp. No leaking when boiler is on and/or the flow temp. is 40 or above (room 'stat at 16). Around 30 to 35, the mains ingress starts to drip (but just a drip; not the flow as previously). This immediately stops when the boiler fires up and flow temp. increases. Obv. still dodgy but this appears to be an improvement. What will happen when we stop using 24/7 htg, I don't know but sooner or later, this'll have to happen. What'll happen when we stop having htg in the spring if there's still a leak, I don't know, as the system will need to be drained down again.

What a palaver ! I'd be tempted to but this Miracle Seal stuff and add to the system but don't want to take any initiative/responsibility for obv. reasons.
 
Think I'd be selling up Mike if I were you if you can't face the disruption of finding the leak.

Good luck.

Tony

BTW, we, ordinary service engineers, ie not manufacturer's engineers are now supposed to test water quality of the heating system and record the result in the boiler service record, I've actually just bought a box of Fernox test strips for this purpose for boilers installed in the last year.

The leak sealer chemicals probably won't show up in the water test which is just basically litmus paper but the test strip is supposed to be sent to Fernox for analysis and record on their app along with the boiler service record wether most guys who are doing services will actually do all of that during a service is moot cause the customer will have to pay for that service so that will bump the cost of a service up and it's hard enough to get punters to have a service done without increasing the cost of it.
 
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Next CP12 (sorry, Gas Safe) inspection will be next November, Tony, when the Magnaclean filter will be inspected/cleaned. Didn't know about the water quality check, though it's my plumber/installer who used it, so the onus, as far as I can see, is on him and effectively on the Vaillant agent who registered it. Anyway, Hobson's choice here; sth had to be done, temporary or not.

Third day of monitoring header tank/ingress/leak etc. in conjunction with the flow temp. No leaking when boiler is on and/or the flow temp. is 40 or above (room 'stat at 16). Around 30 to 35, the mains ingress starts to drip (but just a drip; not the flow as previously). This immediately stops when the boiler fires up and flow temp. increases. Obv. still dodgy but this appears to be an improvement. What will happen when we stop using 24/7 htg, I don't know but sooner or later, this'll have to happen. What'll happen when we stop having htg in the spring if there's still a leak, I don't know, as the system will need to be drained down again.

What a palaver ! I'd be tempted to but this Miracle Seal stuff and add to the system but don't want to take any initiative/responsibility for obv. reasons.

I suppose you should be grateful that you didn't get a combi and pressurise the old pipes!

If it were me, I would attempt to soldier on till the weather warms up (if the leak allows) and then get a company in that specialises in leak detection. Go for a proper fix. With the right gear, they might find and fix in a day.
 
That’s a good idea.

Mike, would you like me to send you my damp meter? It might even pickup the leak in the ground if you follow the pipe run in the concrete? (Can you feel the warmth of the pipes underfoot??
 
Mike, were you charged for the work re the leak sealer?

Not to my knowledge, Tony, and it didn't occur to me that I would

I suppose you should be grateful that you didn't get a combi and pressurise the old pipes!

Not at all; just pissed off as I went through all the pros and cons of the 3 systems (combi, sealed or stay as is) and it became obvious that with my underground layout it was best to safest to stay as is with gravity feed. The plumber agreed and was aware of my reasons. I may add, helped by input from pfm back in the summer when I was getting quotes/advice etc.

If it were me, I would attempt to soldier on till the weather warms up (if the leak allows) and then get a company in that specialises in leak detection. Go for a proper fix. With the right gear, they might find and fix in a day.

Don't have a choice; that's the only game in town at the mo', though contacting my insurance co if the leak fails to seal is definitely a route to take. This was beneficial for my sister when a tenant had an underground leak (and pressure loss) with their combi, and after plumber visits, the insurance co. was called in.

Mike, would you like me to send you my damp meter? It might even pickup the leak in the ground if you follow the pipe run in the concrete? (Can you feel the warmth of the pipes underfoot??

That's kind of you, but I'd imagine that my plumber or associate might have one. However, he did say on Monday that this month-old leak (up to 11 days ago) would have risen to the surface sufficient to detect SOMETHING, even through u/lay and carpet. No signs of damp anywhere, even during the 7 days with no htg and low temp's. Almost impossible to lift carpeting over all remembered pipe runs and the Karndean tiles over mastic substrate in the kitchen/diner/utility are unlikely to allow damp showing through.

Step by step at the mo'. I phoned Fernox's tech. dept this morning and was told my plan of action was right and to turn off the htg for a few hours just to test, now that the sealant has been fully distributed.. However, it'll only work if there's air on the outside of the pipe/joint (as ANY sealant, I guess). Playing for time here, but they did say that, because a seal is brittle, excess expansion and contraction is not good! This is, i.m.o., what caused the break in the first place.
 
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Revising this thread to update those who have helped or have been interested. However, the thread title is totally inappropriate so I'm starting a new one entitled 'Disastrous and disruptive central heating installation; where to now? Since my last post, considerable monitoring and experimentation has taken place, with mixed results.
 
We had a similar situation years back (must be something to do with Norfolk water?

Our problem was solved by going over ground and reconnecting into the system leaving the leaking pipe under concrete, worked very well and no destructive and noisy works.
 
Our problem was solved by going over ground

Not so easy in our place, Tony and it has been suggested that the easier way would be to pipe down from upstairs; again, not straighforward and quite disruptive. This still leaves the 2 largish rads htg the kitchen/diner, though, as they're in a single storey conversion. They could, though, as they were newly installed in 2005, be directly accessible and/or have nothing wrong in the pipework.

Have effectively closed this thread in favour of the other opened yesterday.
 


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