Vaillant Boiler not warming enough

[Steelmasons]

Check flow/return temps in d.40/41 when calling for heat (room stat cranked up high).

 

[ripperuk]

Just switched room stat on 10 mins ago. Readings are:-

D40 (Actual Flow) = 38c
D41 (Return) = 31c

 

[Steelmasons]

10 minutes ago??..Is the programmer calling for heat???

 

[ripperuk]

Yes, it's started the boiler. I've now rechecked and it's:-

D40 = 46C
D41 = 41C

 

[Steelmasons]

That's good..
Increase d.00 to 14kw and monitor flow/return temps. (all trv's open).

 

[picasso]

What would the symptoms be if the diverter valve was sticking (especially after not being used all summer)?

 

[ripperuk]

Okay at 14kw:-

D40 = 56C
D41 = 51C

However, has now dropped:-

D40 = 52C
D41 = 48C

Just to let you know, the room stat is set at 35C and all TRVs are set to 5 Max.

 

[Steelmasons]

Is the burner triangle constant on left hands side of display?
So the rads are now heating with burner staying on?

 

[dilalio]

Okay at 14kw:-

D40 = 56C
D41 = 51C

However, has now dropped:-

D40 = 52C
D41 = 48C

Just to let you know, the room stat is set at 35C and all TRVs are set to 5 Max.

Do you have a magnetic filter?
If so, check the state of it.

 

[ripperuk]

Is the burner triangle constant on left hands side of display?
So the rads are now heating with burner staying on?

What burner triangle?? There is none.

 

[Steelmasons]

Here is the temperature of the Central Heating when the boiler was running earlier:-

Burner status symbol will mirror image bar status symbol.
This is getting hard work , good luck with it..

 

[dilalio]

Burner status symbol will mirror image bar status symbol.
This is getting hard work , good luck with it..

I fell alseep for two hours and woke up to find it still going! I live such an exciting life!

 

[The831Bunny]

Can you confirm what make of controls you have and also let us know the figure you have at D.009 when the boiler is firing.

 

[ripperuk]

I can only sincerely apologise as I know I'm a lot slower than most people to catch on what your exactly asking me to do, but please give me a chance as I'm still trying to learn. Whereas you guys will know the boiler and CH system inside out, I admit that I know very little and I'm a novice. Also I usually require step-by-step instructions as to what you want me to do, exactly what options to choose and what information you require.

Anyway, to make life easier for everyone, I decided instead of posting pictures, I'll post some recorded videos (HOPE this helps!):-

BOILER RUNNING WITH ICONS ON DISPLAY

ME GOING THROUGH SETTINGS. (Watch 30 seconds onwards....Suddenly 66C dropping to 65C)

AS YOU CAN SEE THE TEMP HAS QUICKLY DROPPED FROM 66C TO 54C & THEN BURNER KICKS IN AGAIN

 

[ripperuk]

Can you confirm what make of controls you have and also let us know the figure you have at D.009 when the boiler is firing.

Which controls are you referring to bunny? If it's radiator valves, then they some have trv and some have the spanner-type valves. Not sure about the boiler.

Also do I just start it up and get you the D.009 figure or do you want me to actually run the boiler until it's hot and then get you the figure for D.009????