Vaillant Hot Water Problems?

Or any other boiler for that matter!


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Call: Mark 07515-687740


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Do you have fluctuating hot water temperature? Does the shower run luke warm then hot, luke warm, then hot again?

If so, then I can probably explain why...

Take note, or this is really going to hurt your wallet or purse in a year or two......

Blocked up central heating pipes
Blocked heating pipes
Block plate heat exchanger
Blocked up domestic heat exchanger

These pipes show what’s commonly found inside your heating system and radiators..

You can POWERFLUSH til the cows come home,

it ain’t goina shift this...

And it never does.....  Once the boilers been installed, residual particles get loose, and get pumped into your nice new boiler.

They then collect in the narrowest parts of the boiler (hot water plate heat exchanger) and stop circulation.

We’ve replaced 3 boilers this year, less than 4yrs old, that were powerflushed, dosed with inhibitor, and commissioned in accordance with the manufacturers instructions..... VERY EXPENSIVE!

All three were completely wrecked by this problem.

Because? they didn’t have filter protection fitted. This month (Aug 2010) I’ve had to change 5 plates because they were blocked beyond any point of return. These things cost between £97.00 to £150.00 to buy.

In two cases, the whole main heat exchangers were completely trashed. Once again, powerflushed and treated on installation. Complete waste of time!


This problem drove me nuts on Vaillant, and it still does, because it’s so unnecessary!

Everyone blames the boiler, and it’s giving Vaillant a really bad name. The fact is, it’s not a boiler problem, it’s a boiler problem caused by poor advice from installers, and a willingness to pay peanuts by customers.

Powerflushing has it’s uses, don’t get me wrong, but it’s very limited to the actual longevity of the boiler and system. In my opinion probably only 10% of new boilers require a full powerflush, but ALL NEW BOILERS require filter protection, and inhibitor, especially high efficiency condensing appliances.

If you don’t believe me, you’re more than welcome to accompany me for a week, and explain to people why their boiler’s costing them hundreds to fix, when it’s only a few years old.

It’s like ‘groundhog day’ 7 days a week! complete madness......

So instead of spending £500 on a powerflush, spend £100.00 on a system filter.

Now, there is some light at the end of the tunnel. A few companies have addressed this problem extremely effectively.

Sentinel central heating boiler filter
Magnaclean boiler filter
Boiler installation with a magnaclean
Boiler installation with a magnaclean

Above are some examples, showing the Magnaclean filters we install on ALL our appliances. No filter, no installation! not by us anyway..

And there’s Joe... He just loves pipes!

In my opinion, Adey really have cracked the powerflush inadequacies with the powerflushing filter in conjunction with the new Powercleanse adaptor.

Absolutely superb, we love it!

However, Sentinel have come up with a masterpiece with their system filter. So easy to install, and so easy to clean and maintain.

Fernox TF-1 boiler filter

This is the Fernox TF-1 filter, which is a combination of a Magnaclean and Sentinel filter. It has a powerful magnet, as well as a filter strainer, so you have the best of both worlds.

Alpha Boilers have now included this filter in ‘the box’ with the new Alpha Combi boiler. Yay for Alpha, well done, it’s about time a manufacturer started to address this problem....

Fernox F1 inhibitor
Fernox logo
Viessmann boiler installation
Magnaclean and vaillant boiler installation
Magnaclean fitted
Joe installation of boiler and MEGAFLO


It is a criminal offence to work on a gas appliance if you are not qualified, and licensed to do so.

ALWAYS consult the manufacturers user instructions for guidance. The instructions above are for guidance only. If unsure of any procedures, call a boiler specialist, who holds the relevant qualifications, and GAS Safe Registration.

Spirotech boiler filter
Spirotech filter