Boiler gas consumsion

[man100]

I have a two and a half year old Baxi du o tec 28 boiler.

A few weeks ago a Baxi Heateam engineer came to replace the the spark electrode with a modified unit, he also replaced the spark generator.

He made several tests and checks on the boiler with some form of meter and was on site almost an hour.

I have always kept a daily record of gas usage updated each day at 08.30 well back into last year, since the visit of the engineer I am sure its using more gas.

The components which were replaced would not cause this, is it possible that with a modern boiler of this type he could have adjusted something to causing increased gas consumption.

The original spark electrode kept loosing its gap hence the change.

 

[dcawkwell]

Did he perhaps set the central heating water temperature or the hot water temperature to their highest. If so turn them down again.
If the boiler is running at full temperature there will be less condensing
and therefore less efficiency.

 

[man100]

Did he perhaps set the central heating water temperature or the hot water temperature to their highest. If so turn them down again.
If the boiler is running at full temperature there will be less condensing
and therefore less efficiency.

No he left that at 70 as it was, now as regards this setting some time ago I spoke to Baxi technical to ask about the best setting for this control to obtain max efficiency and was informed that flat out at 80 would be the best.

They also said that the return temp. at the boiler should be a minimum of 13 degrees less than the outgoing, I have a clip on meter at the boiler on the return which indicates I have 15 degree difference.

This difference remains the same when output is at 70 or 80 I have not tried the output any lower than 70.

At 80 room warm up is faster than at 70 the room stat turns off sooner.

But to go back to my first question what else could cause increase in gas.

Oh and domestic has always been at full.

 

[dcawkwell]

Did he perhaps set the central heating water temperature or the hot water temperature to their highest. If so turn them down again.
If the boiler is running at full temperature there will be less condensing
and therefore less efficiency.

No he left that at 70 as it was, now as regards this setting some time ago I spoke to Baxi technical to ask about the best setting for this control to obtain max efficiency and was informed that flat out at 80 would be the best.

They also said that the return temp. at the boiler should be a minimum of 13 degrees less than the outgoing, I have a clip on meter at the boiler on the return which indicates I have 15 degree difference.

This difference remains the same when output is at 70 or 80 I have not tried the output any lower than 70.

At 80 room warm up is faster than at 70 the room stat turns off sooner.

But to go back to my first question what else could cause increase in gas.

Oh and domestic has always been at full.

The cooler your operate your boiler the better the efficiency or why
would they have temperature compensation that reduces flow temperature in warmer weather. So much for Baxi technical. If the return temperature is more than about 50 ish reduced condensing occurs and efficiency drops.
Perhaps you are running your central heating longer in cold weather or have increased the wall thermostat slightly.
Adjusted TRVs therefore drawing more heat.
Colder temperature therefore house loses are greater.