Not gas safe but...

[secret squirrel]

Let me just say that, I'm not gas safe, have not done any gas exams and have no intention of working on boilers, BUT:

How does a boiler work?

I understand the pipe work, gas in, primaries etc, I also understand the pipe work (ish) on a combi. I also get that the boiler is controlled by other components and how they work in unison,

What happens in the boiler when it is told to fire? What opens the flow of gas? What is the air pressure switch? I don't mind buying a book but I would like a little understanding of it.

So, if someone could spend 5 mins typing a reply I would be grateful. Please, please don't get too technical.

 

[Puddle]

when you say how does a boiler work,do you mean a combi or a normal boiler or both ?

 

[stevetheplumber]

combis now are basically computer controlled all the info from sensors is fed to a pcb which switches on the pump and gas valve

rough guide is for heating,fan runs air switch makes pump runs which makes flow sensor which open gas valve and fires ignition if flame is sensed boiler continues to fire if not it locks out
on hot water tap open activates three way valve which makes dhw switch which fires pump then same as heating
some boilers work in different order some have various extra stages
temeratures are controlled by stats of thermistors causing gas valve to modulate or close
there may also be verius satey devices. low water preasure switches over heat stats and oxegen depletion devices .
most manufacturers include a sequence chat in the install literatrure try reading some to get the idea

unfortunatly they no longer make any basic boilers

 

[secret squirrel]

Thanks chaps,

Puddle just needed to understand both types a little.

 

[Plouasne]

Now just to confuse you even more, try this link

Wall mounted condensing gas boilers - HYDROCONFORT - FRISQUET - Gas boiler

Then click onto the top picture and see what I call proper a combination boiler, not an overgrown Ascot

The link below is good even if it is in French, because it gives the positions allowed for a balanced flue boiler terminal, its like one I helped to fit, and the first sold by the merchants in the area, its a nice beast even if it is "lumpy"

http://www.atlantic-francobelge.fr/...0-b(v)r-notice-tech-atlantic-franco-belge.pdf