Eli5 How can one small flame in a boiler be enough to warm a whole houses central heating system?

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Eli5 How can one small flame in a boiler be enough to warm a whole houses central heating system?

In: Engineering

7 Answers

Anonymous 0 Comments

Ever boiled water on a stove? It happens right? You have a pan of cold water, then minutes later it’s boiling.

But sure, the house is bigger.

That’s why instead of having a person checking when the water is hot your water heater comes with an automated control system to keep the water hot through the day.

And I don’t know about you, but the only little flame there is the pilot, the burners are quite the spectacle, specially when they first light up.

Anonymous 0 Comments

The pilot light which is always burning is a small flame. But when the boiler is on and heating that pilot light ignites lines of burners (like it does in a gas oven) that are used to heat the boiler. When the boiler turns off gas supply to those burners turns off and they go out but the pilot stays it.

Anonymous 0 Comments

Only the pilot light is a “small flame”, but the pilot light isn’t what is actually heating the water that then heats the rest of the house. There is a whole set of burners that get lit by the pilot light when the burners turn on.

Anonymous 0 Comments

It’s not a small flame, it’s rows of burners that ignite from the pilot light when gas is supplied. The burners create heat that’s 100’s of degrees hot and the air then flows through the ducts and comes out the registers still very warm. That warm air mixes with the existing air to meet the desired temperature.

Anonymous 0 Comments

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Anonymous 0 Comments

Depending on the size it could be 20,000 -100,000+ btu of flame… That is an incredible amount of energy…

To put in perspective a high end gas stove like a wolf is about 20,000 BTU total between all the burners….

Anonymous 0 Comments

The small flame you see is called the pilot light – this is a small, single flame that is kept lit permanently as a way to start the main gas flames of the boiler – when the boiler is activated properly it will turn on additional banks of flames (lit by just turning on the gas flow – the gas will fill up the boiler until it reaches the pilot light and ignites). These main banks of flame are what does the main bulk of the heating.

When you turn off the boiler, the main jets will turn off, but the pilot will remain lit, ready for next time the boiler is used.

The problem you will hear being mentioned in reference to the pilot light is when it gets blown out – with no pilot light, you have no way of igniting the main gas jets of your boiler, meaning it won’t work until you can get the pilot light relit.

As for why they use a pilot light? It is just the most effective and reliable way to light a boiler. While you do get other systems like piezo/electric igniters, generally they are just not as reliable or easy to use on a timer (notice how it often takes a few clicks to light a gas cooker – you would need to find a way to monitor this inside your boiler), and the pilot light uses such a small amount of gas it isn’t considered an issue.