Vaillant Boiler not warming enough

[dilalio]

Stuff what? Tomorrow’s turkey?

 

[flameport]

Would all you engineers recommend a new PCB to save the hassle.

If you want any kind of answer, then please provide details here: https://www.diynot.com/diy/threads/vaillant-boiler-not-warming-enough.500428/

People here provide their time and expertise for free - it's unlikely anyone will want to read through 8 pages of unrelated posts from 18 months ago in an attempt to guess at what your problem might be.

 

[Micahel Hall]

I don't disagree with any of Steelmasons posts as I think he's spot-on, but I've tried the both the 18kw & 30kw setting and the same thing is still happening, where the water warms upto 75C and then quickly drops to 60C and then cycles back up to 75C etc. That's why I've looked at other options, such as the radiators themselves. They are slightly over luke-warm to touch.

ripperuk You have more than likely solved the problem of the temperature anomaly in you heating system due to this post being old.
The first bit of basic advice about heating systems id to take not a jot of notice of those who say a heating problem is not atechnical problem because it is most definitely a technical problem.........
The first thing to evaluate are the temperatures of the flow and return heating mains which vary drastically on most systems in the UK because of incorrect design. There can of course be inadequate circulation due to debris in the heating water but if one looks at the Boiler Fitting Instructions it will be seen that a minimum temperature drop across the flow and return AT THE BOILER must be 11 C which used to be 20 F in my younger days if good practice re pipe sizing was adhered to. The temp across each radiator also approximately matches that mentioned.
It also states in no uncertain terms that the water must be clean due to about 10mm diameter Heat EX bores. ( mud or lime = HEX death)

These laser thermometers not dear but most electricians and Heating eng's have a laser thermometer in their kit and it's pretty well essential to
quickly confirm the basics of temp behavior in any heating system. A cheap clamp on thermometer works but is fiddly.

When the basics have been checked the PCB controlled evaluations and parameters must be checked and as another contributive post said
there are sites that look at the Vailant problems associated with those boiler circuit boards.

I found it interesting but also disconcerting to see that a boffin who quotes very much data on the Vailant PCB & associated boiler systems
says that the boiler computer can 'change it's mind' and deliver what the customer and not least the heating engineer does not want!
It seems that the settings which are seen and adjusted on the digital screen as per the Boiler fitting instructions must be carried out with the utmost accuracy as should all heating tasks but it seems disgruntling that most of the ridiculous writings herein fall very far short of accuracy and do not give straight answers. This may be accidental through lack of Technical knowledge but it could in some instances be by intent.

 

[dilalio]

ripperuk You have more than likely solved the problem of the temperature anomaly in you heating system due to this post being old.
The first bit of basic advice about heating systems id to take not a jot of notice of those who say a heating problem is not atechnical problem because it is most definitely a technical problem.........
The first thing to evaluate are the temperatures of the flow and return heating mains which vary drastically on most systems in the UK because of incorrect design. There can of course be inadequate circulation due to debris in the heating water but if one looks at the Boiler Fitting Instructions it will be seen that a minimum temperature drop across the flow and return AT THE BOILER must be 11 C which used to be 20 F in my younger days if good practice re pipe sizing was adhered to. The temp across each radiator also approximately matches that mentioned.
It also states in no uncertain terms that the water must be clean due to about 10mm diameter Heat EX bores. ( mud or lime = HEX death)

These laser thermometers not dear but most electricians and Heating eng's have a laser thermometer in their kit and it's pretty well essential to
quickly confirm the basics of temp behavior in any heating system. A cheap clamp on thermometer works but is fiddly.

When the basics have been checked the PCB controlled evaluations and parameters must be checked and as another contributive post said
there are sites that look at the Vailant problems associated with those boiler circuit boards.

I found it interesting but also disconcerting to see that a boffin who quotes very much data on the Vailant PCB & associated boiler systems
says that the boiler computer can 'change it's mind' and deliver what the customer and not least the heating engineer does not want!
It seems that the settings which are seen and adjusted on the digital screen as per the Boiler fitting instructions must be carried out with the utmost accuracy as should all heating tasks but it seems disgruntling that most of the ridiculous writings herein fall very far short of accuracy and do not give straight answers. This may be accidental through lack of Technical knowledge but it could in some instances be by intent.

Dude... check the date stamp of the posts you’re replying to

 

[Micahel Hall]

Dude... check the date stamp of the posts you’re replying to

I notice the date and also commented on it if you have the time to peruse my post?
I do also notice that in this particular discussion same as many others I have looked at that the person asking for help has been left hanging on a string with no satisfactory or helpful conclusion to their question/s. This may well be that some on this posting do not like amateur's asking for
advice but in this case I am no amateur. However some of the so called advice is misleading to say the least. Much of it is not to the point and irrelevant to the question.
In any case if you say my posts are out of date how come you so readily 'latched onto this post?

 

[dilalio]

If you want any kind of answer, then please provide details here: https://www.diynot.com/diy/threads/vaillant-boiler-not-warming-enough.500428/

People here provide their time and expertise for free - it's unlikely anyone will want to read through 8 pages of unrelated posts from 18 months ago in an attempt to guess at what your problem might be.

See above @Micahel Hall (is it Micahel or Michael?)... your post hijacked an old thread and has been moved to a new thread by the mods! Click the link above and continue this topic there!

Then you may get the response you are looking for! Or maybe not!!