Cheap boilers!

Lord Hall is at it again!!!! Lunacy personified.

Matt, is at it again!! Shear lunacy.

He does Chav.

A handyman who is dangerous.

Good on Valliant, knows frig all about quick recovery cylinders as he can't tell the difference between a Part L and a quick recovery.

Thinks cast iron boilers, tanks and cylinders are superior. Did not know that condensing boilers can go to 109%. An expert in boilers not know something fundamentally basic? As Tomlinson would say...My Arse!!!

Exactly! You want the best cost effective system. This bunch of know-it-alls would not know one as long as they have a hole in their botties.

Good, since they can't. You would need the intellect of willy cheese to believe they could.

They can oh amateur boy. The scale of measuring takes into account latent heat so goes up to 109%. The normal non-condensing scale only takes into account sensible heat which goes up to 100%. Anyone who know about boilers would know this, which you clearly do not.

"Sensible Heat". That's a new one. Is this what they taught you when you went to university?

Did they call Latent Heat "Silly Heat" to make it clearer for you?

You have explained this in a confused way.

The original method of measurement (use of Net Calorific Value) was on the basis that latent heat would not be recoverable and is thus ignored.

This means that non-condensing boilers achieve less than 100% using the NCV figure for the fuel.

Since a condensing boiler can recover latent heat, it is able to recover the portion that was ignored when NCV numbers for a fuel are considered.

Therefore, *measured on the NCV scale*, figures of more than 100% can be shown. However, this is misleading, because of course it is not possible to achieve greater than 100% efficiency if the Gross Calorific Value (GCV) of the fuel is used.

Since condensing boilers are recovering some latent heat, on the same basis that NCV was used for non-condensing boilers, GCV should really be used for condensing boilers because it is an indication of what the boiler is achieving out of the total possible.

GCV for natural gas is 11% higher than NCV. Thus a boiler which has an "efficiency" of 109% on the NCV scale in reality has an efficiency in terms of the potential of the fuel of 98%.

However, to make the comparison between non-condensing and condensing products correct in terms of the fuel actually paid for, the same scale should be used.

If a GCV basis were used, non-condensing boilers with efficiency of say 80% on the NCV basis would have a GCV efficiency of 72%.

This would also have meant re-stating the figures for existing non-condensing products as condensing ones came on the market. The industry chose not to do this, especially as it has the marketing advantage of being able to claim figures of > 100% for condensing boilers on the NCV scale.

The reality is that the genuine efficiency when all capabilities of the fuel are accounted for cannot exceed 100%.

Oh NO!! he doesn't know what sensible heat is. Oh my God and they let Matt out in the street too.

Yawn...

No oh mentally challenged one, the scale does *not* take into account latent heat. That is how you can come out with erroneous results that exceed 100%

Stick the right numbers into the equation and you will get

For all I've got Dr D killfiled, the above terms sensible heat and latent heat are correct, as any physics textbook will show.

Sensible heat is that which can be sensed, or felt, by a change in temperature.

Latent heat is that which is hidden, by not causing a change of temperature.

Keep it that way as you come across as a tosser.

Yep. If I say it is always right.

Chav, life is boring.

That is what I said. Are you a parrot?

That is what I said. Are you a parrot?

Not you or Matt/Lord Hall.

You prattled:

Can you not see the difference?

The message from Mike Tomlinson contains these words:

I long since come to the conclusion that timegoesby is Dribbles brother and judging by some of the questions he has asked recently he is even more clueless.

"Roger" wrote overt and shamess Rogerness in message news: snipped-for-privacy@nospam.zetnet.co.uk...

Sad but true. Roger is a sad case from Essex.

You didn't know, but are trying to make out you did. The uk.d-i-y Lunatic Association strikes again.

I normally don't try to lengthen these pointless threads.

However almost all gas appliances I've so far seen quote their input rating based upon the Gross CV not on the Net CV. This fact together with the same basis being used by SEDBUK means that all boilers are given efficiency value in the range 0-100%. Only condensing boilers can achieve values above 90%.

This old chesnut comes up from time to time.

Lost the plot again I see...

Chav, you didn't know to even lose the plot.