Vaillant boiler from hell

[talerddig]

We just replaced our boiler with a Vaillant ECOTEC and two months on it's driving us mad!
The pressure regularly drops to zero after 36 hours and fails with an F22, leaving us having to manually build it back up.
There are violent bubbles and sloshes when it kicks in in the morning from cold at low pressure
some radiators downstairs are cold at low pressure
Takes over 30 seconds to get hot water on some taps initially
hot water is milky

The boiler is a condenser and replaced an old combi that rattled for England, but at least gave us heat when and how we wanted. The radiators and piping are the same, the only difference is that each radiator has new valves and there is no hot water tank and an empty airing cupboard.
We had this done by one of the large power providers and their engineers are firendly, polite but don't solve the prob! Some mutters have been made to their being a leak in the existing piping, but surely that was the one thing that hasn't changed?

If anybody has some ideas about what might be going on, please, please let me know!!!!

 

[Gasguru]

You say your old boiler was a combi and you had a hot water tank, either the tank was redundant, the boiler was not a combi or you had an unusual setup (very few installations run a cylinder inconjunction with a combi). Do you mean the tanks (cisterns) were in the roof space?

Did the previous system have a small header tank in the roof? If so it operated under low pressure and any small leaks would have been topped up automatically (although not good longterm for the system).

Your new boiler operates under higher pressure and is a sealed system. Any leaks (even very minor) will cause the pressure to quickly drop.

In addition good installers will clean the system (often by powerflushing) and this can result in leaks appearing.

Did the installer not tell you the risk when changing to a sealed system...should be in their T&Cs.

Have you checked the obvious...safety valve pipe from the boiler...look outside, new radiator valve connections to pipework/rads. It's possible the new boiler has an internal leak to the condensate pipework but this would be very unsual. Otherwise the leak is on the pipework.

 

[simond]

I think your title is misleading. I very much doubt your problems have anything to do with the boiler.

 

[talerddig]

Thanks, yes obviously not a combi! the tank was in the roof

No they didn't explain the pitfalls of my reckless purchase!

They have suggested dumping a liquid sealant in the system that may plug any leaks. It sounds as if this may help. Thanks, i'm a bit closer to understanding why it's all happening and we'll check the obvious to make sure.

 

[talerddig]

simond.

To a lay person, the only change to the system has
been what has been replaced ie the boiler and valves.

I think gasguru has made some suggestions above that tells me what you're getting at.

 

[gas4you]

Forget the leak sealer. Your leak sounds way too big for this to cope with and if it did it would probably only last a couple of months.

Pressurise the boiler, isolate it at the F & R valves under it, leave as long as possible. If no pressure drop then it is a leak on your system.

I realise that this is very frustrating for you, but I feel that you are blaming the boiler prematurely this time.

I don't think your installer sounds that good if all he's offered is a leak sealer

 

[talerddig]

Thanks gas4you

Yes, you have ht the nail on the head. As a lay person, all I see is a boiler that loses pressure. i think I'm resigned to it being a leak now though!

Problem is, the leak doesn't show anywhere. We had one radiator replaced as the connections were corroded. Still no joy. No damp patches anywhere.

The plumbers now talk of ripping up floorboards. All well and good, but it sounds a bit random and I'll be left with half a house after!

Nightmare situation, but what can you do except carry on looking for the damn leak.

Thanks for the advice

 

[The Baker]

"We had this done by one of the large power providers "

Did the large supplier carry out a comprehensive survey?

As the water changes colour, goes milky as it reaches a "hot" temperature it seem that your boiler is OK on that bit of its job, its just the time you wait for hot water thats not to your liking.

Cant remember but feel sure the model of boiler you were sold has a "keep the water hot" facility that will minimize the time for hot water to reach the taps.

As an independent installer (one man band) I would be interested in the price of the job.

In all fairness to the Large Power Provider, they will want you to be delighted with their work so get them back, they cant fix it if they don't realise its still broke.

Their workers are go through a training day where they learn to be nice when they call so as to defuse the tension for them, and wear you down to the point where you give up, and come onto this site for help.

Have you considered asking for your money back?

Tim

 

[EliteHeat]

Did the large supplier carry out a comprehensive survey?

What? an under floorboard survey?

Have you considered asking for your money back?

What is that supposed to mean? as a previous poster said, the terms and conditions should have covered the possibility of either an existing and unnoticed leak on the OV system or the power flush (if any) exposing a latent defect.

Are you suggesting that it is the installers responsibility, within the bounds of the original quotation, to lift floorboards, laminate, parquet etc trying to find a 20 year old leak?

 

[ChrisR]

talerddig you aren't likely to get your money back!
Handwringing by you or the installer won't fix it.
It has to be dealt with, however distasteful it may be!

You do have to make sure the steps outlined above are taken.
Check boiler carefully.
Check rad valves
Leave the boiler off, isolate it and use behaviour during that time and when reconnected, to start to isolate the leak.
If the leak is on the pipework, it may need splitting, by isolating valves, then key boards lifting.

There do exist specialist companies which find leaks by a combination of hi-tech means, but how much they would promise on your particular system I don't know.

 

[giblets]

It's a shame that the ramifications of converting an OV system to a sealed system don't appear to have been fully explained to the OP at the time of survey even though they would be covered in the T&C's. Regretfully most customers only look at the bottom line and not the small print.

 

[Agile]

It's a shame that the ramifications of converting an OV system to a sealed system don't appear to have been fully explained to the OP at the time of survey even though they would be covered in the T&C's. Regretfully most customers only look at the bottom line and not the small print.

And most commission earning salesmen are more interested in their commission than explaining potential problems to the sales prospect.

However, the customer is mostly to blame! They dont want to be told about problems.

If I went to a prospective customer and spent 30 minutes explaining all the possible, but unlikely, problems which might arise, I know from my experience they would choose a more expensive contractor who never mentioned any problems.

Tony

 

[tonybhoy]

It's a shame that the ramifications of converting an OV system to a sealed system don't appear to have been fully explained to the OP at the time of survey even though they would be covered in the T&C's. Regretfully most customers only look at the bottom line and not the small print.

And most commission earning salesmen are more interested in their commission than explaining potential problems to the sales prospect.

However, the customer is mostly to blame! They dont want to be told about problems.

If I went to a prospective customer and spent 30 minutes explaining all the possible, but unlikely, problems which might arise, I know from my experience they would choose a more expensive contractor who never mentioned any problems.



Tony

I tell every customer in writing and verbally there could be a possibility of leaks and still get the work in the majority of cases.

In my experience most customers know there is a possibility of leaks if the choose to have a pressurized boiler installed to an old OV system because they have already been told by other companies who are quoting or by asking friends or doing some research.

This is one of the most common questions I am asked during a survey that and are Combi boilers really ****e

 

[stardanny]

What cause hot water to go milky? And why? And what the cure?

There a easier way to find leak, put pressure up to max ( when PRV blow ) and walk around and listen for pishing sound. May help you location pipe leak.

Dan.

 

[andytheplumber]

Check the ceilings for damp patches. Put your hand on every radiator valve. these should be bone dry. If you cannot find anything than the leak is under the floor. So you have to lift up the floor find the leak and repair it. If the drain valve is out side the house this could be leaking.