Thread: shed heating

RE: Radiant Heating

Originally Posted by Midnight Man

. . . .These will keep YOU warm, not the ambient air and everything else around it. These work completely differently than a normal heater - I won't pretend to fully understand them, but you stand under it and it feels nice and warm.

I suspect this would be true even if you have the dusty running and venting outside.

Radiant heaters output infrared radiation which easily travels through air to directly excite the molecules on the surface of your skin and clothing which is transferred into your body.
In a closed room they will also eventually heat up everything around you and would be more effective in a small shed since most of the air that is heater rises.

Fires outside do the same thing but it also explains why you fry on the side exposed to the fire and freeze on the other.
Fires inside do the same thing initially but eventually the warm the air and room itself providing heat from all sides.
By comparison an AC generates little radiant heat and heats by connection and conduction. the AC heats and moves air around a room which carries the heat from the AC to you .

The attached pic is of my forge for which 2800 CFM of air is used as exhaust extraction (mainly CO). This is about 2x that moved by a 6" duct connected to standard type DCs. Most of of forge heat is removed by the high air flow but it still heats the whole shed and operator up to over 50ºC in about an hour on a cold winters day.- Can't use it at all in the summer for more than about 20 minutes.

How effective radiant heaters would be while a DC was running depends on a few things.
The main ones are the temperature differences and amount of flow or more specifically flow past the operator.
If the outside air is freezing then it could cool your skin and clothing faster than that the heater heats.

the amount of flow past the operator depends what you are doing - if you are turning and have sufficient air flow past you to clear the air of fine dust then the air flow will tend to outweigh the heating. It should be less of a problem for other machines.

Originally Posted by Midnight Man

To heat a shed in winter, you buy one of these (or more, depending on where you stand & work): https://www.bunnings.com.au/heatstri...eater_p3170733

Or you could just get one of these https://www.bunnings.com.au/ironhors...eater_p4441954 for a tenth of the cost and run it 40 hours a week all winter and still come out cheaper (Purchase price and power cost) than just the purchase price of Midnight Man's radiant heater at the same wattage.

Speaking of radiant heaters, a new pub went up in a design of about late 1800s. The big function room had a HUGE brick fire place in it. I went to a summer function in it and wondered how efficient the heating from it would be. I went to a function in winter and the patrons were in a 5 meter semi circle in front of the fire place. It was very well received

Originally Posted by doug3030

Or you could just get one of these https://www.bunnings.com.au/ironhors...eater_p4441954 for a tenth of the cost and run it 40 hours a week all winter and still come out cheaper (Purchase price and power cost) than just the purchase price of Midnight Man's radiant heater at the same wattage.

I wonder what a red hot element does to the fine dust - probably does a good job of converting it to CO2?

nice idea, Struth!! $600. i need to make a lot more from woodwork before i could afford them.
I've got 5 acres of bush with which to scrounge wood and fell a few trees for firewood so we might be tackling a heater project. Heres a pic of the starting point, a door for the bottom, new sturdy home grown hinges, not ones where when you light the fire the plastic in the hinge melt and the pin falls out and the door falls off!! it was funny when i look back and no i didn't put them on.
IMG_2217.jpg

Originally Posted by BobL

I wonder what a red hot element does to the fine dust - probably does a good job of converting it to CO2?

Does it really matter? All the fine dust gets collected at the source, doesn't it?