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Re: Low heat value, or inefficient boiler.
Posted: Mon. Jan. 28, 2019 1:08 pm
by McGiever
That all makes sense...nice that you were able to work this all out for yourself, I'm impressed.
Re: Low heat value, or inefficient boiler.
Posted: Mon. Jan. 28, 2019 1:43 pm
by franco b
Excellent reasoning. Just what is needed for better designs.
Re: Low heat value, or inefficient boiler.
Posted: Tue. Jan. 29, 2019 2:54 pm
by Bubbalowe
Just read through and think the barrel boiler pretty cool. Barrel stoves pass heat faster than cast iron so think copper laying on tin should have good heat transfer? In my beer making hobby I've used immersion style wort chillers and counter flow chillers, same principle, to absorb heat. Something to consider is flow of water ie, slow flow down to allow more heat to be absorbed, 99C out being best. Measure water temperature into boiler, out of boiler, into house and back to boiler to get the most. Maybe just a gate valve inline for control?
Re: Low heat value, or inefficient boiler.
Posted: Sun. Apr. 07, 2019 8:14 pm
by DR ARNETT
U MIGHT TRY ANTHROCITE NUT COAL FROM TRACTOR SUPPLY IF IT'S AVAIABLE WHERE U ARE I GET IT STARTED W/ WOOD THROW IN 'BOUT 30-40 LBS . ONCEIT GETS GOING BANK IT BACK IT SHOULD GO 6-8 HRS . MY HOME IS APRX. 400 FT SQ. I USE NATURAL DRAFT I DO HAVE A GRATE THOUGH. IF U CAN GET BIG CHUNKS OF BIT. COAL [ 10'' OR SO ] THAT WORKS BETTER.
Re: Low heat value, or inefficient boiler.
Posted: Tue. Apr. 09, 2019 4:35 pm
by BigBarney
I like the way the grate looks but in reality the size is way overkill.
I guess 20" wide x 26" deep you have enough grate area for at least
200,000 btu of output , with descent coal. I believe grates this large
would be hard to shake even in three sections.
Typical grates of ~250 sq in get about 350 btu per sq in .,
so you have enough grate area for ~190,000 btu boiler .
At 20 watts per sq ft your home needs 4KW of heat or
~12,500 btu per hour on a 10* F day.
BigBarney