Vaillant ecoTEC plus 612 query

[HiQ]

Hello
I have a new Vaillant system boiler which is very slow to respond to heating demand.
When it starts in the morning and there is a high demand for heat it only fires up to about 1/3 power and stays there for about 30 minutes, or more, before going up to full power.
I touch the return pipe entering the boiler to confirm that the return water temperature is cool throughout.
My installer checked all the settings are at default and does not know why it is very slow to respond to heat demand.
Is this normal behaviour for this boiler?, or should I contact Vaillant?

Many thanks for you thoughts

 

[jtsplumbing]

Take it installer has checked gas rate / working pressure / took analyser readings if all these are ok then as its a new boiler don't mess around with it or you will invalidate warranty, call out Vaillant

 

[HiQ]

Thank you jtsplumbing.
My plumber did all those measurements and recorded them on installation and checked them again when called out.

 

[oil gasman]

Thank you jtsplumbing.
My plumber did all those measurements and recorded them on installation and checked them again when called out.

if he has done all of this and insured all the gas pipe size is correct , inc all the other measurements and as jts said get vaillants in to check the boiler

 

[Leo21]

He needs to set the kw manually on the boiler, the boiler is self ranging. But it doesn't always work.

 

[drip-dry]

These boilers think they are a lot cleverer than they actually are.......Think you might have a water circulation problem

 

[newcastle phill]

Im thinking along the lines of leo too.
Fitted one and had to change the settings for gas rating.
When the boiler was left to its own devices I was about 9kw shy !.
Went into settings and manually selected high output - sorted

 

[HiQ]

Im thinking along the lines of leo too.
Fitted one and had to change the settings for gas rating.
When the boiler was left to its own devices I was about 9kw shy !.
Went into settings and manually selected high output - sorted

Apologies or my delay in thanking you for your posts - I did not get the email notification of replies.

If D.00 is changed from auto to say 12KW(max) - will the boiler still modulate fully down when there is little heat demand?

Many thanks

 

[Leo21]

Yes it will modulate down as required. 12kw isn't a lot though, what's it powering? Number of rads etc

 

[doitmyself]

Yes it will modulate down as required. 12kw isn't a lot though, what's it powering? Number of rads etc

12kW may be more than enough for a modern house which meets the current insulation requirements. (More may be required to heat a fast recovery cylinder.)

The heat loss is the deciding factor, not the number of rads.

 

[HiQ]

Yes it will modulate down as required. 12kw isn't a lot though, what's it powering? Number of rads etc

I am pleased to hear it will still modulate down, and have changed D.000 to 12KW.

The property is a modern 3 bed bungalow on the South Coast only occupied by the 2 of us. When it does eventually get up to full power it does the job OK.

Many thanks

 

[Leo21]

12kW may be more than enough for a modern house which meets the current insulation requirements. (More may be required to heat a fast recovery cylinder.)

The heat loss is the deciding factor, not the number of rads.

Hi, my names Leo. I'm a qualified heating with thirty years experience in the plumbing and heating industry. All hands on I might add. And you?

 

[Dotty]

Hi, my names Leo. I'm a qualified heating with thirty years experience in the plumbing and heating industry. All hands on I might add. And you?

You started out as an egg, didn't you.....

 

[Leo21]

You started out as an egg, didn't you.....

Didnt we all?

 

[HiQ]

Update from OP...
Boiler is now working much more to my liking - giving full power as and when needed.
Many thanks to all.