How does water heat inside a boiler

[PatPend1ng]

Hi,

I know that the water for both the CH and hot water is pumped around and through the boiler where the gas heats the water as it flows through.

My question is: when the hot water is being heated but the CH off does the same amount of gas burn as when both CH and hot water is turned on? or does the boiler burn more gas if it knows both CH and hot water need heating?

i.e. can one reduce the gas used if you always make sure the water is heated when the CH is on and save having the gas burning twice.

thanks

Pat

 

[45yearsagasman]

It depends on the boiler type.A combi will always use max gas rate to heat domestic hot water(it will modulate down during he process)The same boiler may be range rated to the heating load and will use less gas.I really don't see your point as whatever you are heating requires a designated amount of gas to do the job irrespective of when you run your system.

 

[PatPend1ng]

thx for reply.

I'm thinking that my non maxi boiler has a set of gas burners and two pipes flowing through them - one CH, one hot water. one or both could be on at any one time and the same amount of gas is burnt to heat one or both. or is this not the case.

Even with the thermostats monitoring the temperature of both at the hot water tank and rooms respectively, I wondered if boilers could increase or decrease the amount of gas burnt depending on whether it is being asked to heat CH and / or hot water at any one time.

If the same amount of gas is burnt irrespective, then it will be more efficient to always have both on at the same time and not separately. Or perhaps you can tell me why this is not the case

 

[45yearsagasman]

What is a non maxi boiler? Modern boilers do adjust their gas rate according to the load put on them.Older boilers do not,and the burners are either on or off.With respect I don't think you understand the physics involved with central heating systems.

 

[PatPend1ng]

you are right, of course, I didn't understand it. That's why I asked the question. Pity you could not help as I still don't understand.

 

[kevplumb]

What is a non maxi boiler?