Published on 12, July, 2020
For those who are interested in obtaining heat in a more independent manner than Main "utilities" there is the diesel cab heater as made in china and purchaseable for around £100.
Recommended fuel is road diesel at some stupid price, red diesel at a reduced but still unacceptable price or kerosene which in small amounts is obscenely priced.
I am now in a position to make quantitive and qualitative measurements as I have a second heater installed here in the garage from which I do much of my posting and other activities.
I can also measure outside air temp and indoor temps, and currently my heater is adding ten degrees to my garage where I sit and 5 degrees at the colder draughtier end.
It feeds a huge cardboard tube which both acts as a full length "radiator" and also directs warm air to where I sit for extra comfort. Currently it is running on road diesel whilst I negotiate my next purchase of kerosene.
Yesterday it used about 4 litres running continuously from 12:30 until 02:30. I tend to fire it up at high power initially until the tube gets warm then drop it back to 3/4 power for an hour or so to get some general warmth into the area, then I settle down to half power as soon as I am warm to keep the temps stable.
I eventually managed to get the other heater to swallow waste oil thinned with stale petrol only after I added 7 litres of road diesel to the 13 or so of mixed fuel I had made up already. The down side is that low power operation produces visible blue smoke...
There are two modes of operation thermostat where the heater brings the thermostat temp up then slows itself to suit, or dropper mode, where you control the speed at which the fuel is added and the heater controls it's fan speed. It seems that dropper mode allows you to explore various regimes of combustion, some of which are noticeably more efficient than others.
Future experiments will include more alternative fuelling investigations using the heater in the garden workshop, and developing a way of measuring efficiency between fuels more accurately here, until the weather improves at any rate...
4 litres is quite a bit of cost Sperg.
My immediate reaction is that you should build a cardboard radiator to contain and circulate the hot air you produce (at some stage)....just having a long tube with an open end will result in very deviant pockets of temperature here and there?
I will be interested in what your prelim records indicate. Good for you - this sort of stuff is always fun.
Yep, at 75p a litre for kero that's 3 quid a day to heat an uninsulated garage. OR closer to a tenner a day if you use road diesel...
But 14 hours runtime at a minimum 2KW (these heaters usually do 2-5KW) is 28KW/hrs. Currenlty I believe nat gas is priced at 12p a kw/hr and if my mintal arithmetic works, at kero prices that compares very favourably indeed, even before I start adding any "free of cost" ingredients to further reduce the cost of my fuel...
I could see me ending up making an on the fly fuel reservoir blending system that basically adds more waste oil when heat demand is high, and less when the heater needs to run at a lower power output.
Also, Kerosene CAN be obtained at a very low cost indeed from ones local airfield if one has the contacts, as once they remove it, they don't put it back during servicing the bigger aeroplanes.