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...
Would you need to have it on continuously for that long if you made sure the warm air couldn’t escape? Could you line the cardboard tube with some kind of foil? Have you made sure that all of the windows and doors are sufficiently sealed? I’m just wondering if that would drastically bring the cost down.
Zoe - you are right - all empirical evidence that I have ever read or researched suggest that improving the air-tightness of the space and insulative properties of the "envelope" that you are trying to heat are the FIRST things to tackle if you are aiming for cheaper heating costs and a more sustainable planet..............but to be honest, Ispergs experiment is way more interesting !
And if I do the insulation before the measuring, 1, the temp cycles will be longer making it more tedious, and 2. I'd like to have measurements of which improvements make the biggest difference per expenditure. ( could google it of course, but I learn best and deepest through "DIY"...