Steve, see the comments about them in the recent Vevor thread

It's possible to work this out , basically comparing the cost of an oil heater with the cost of electric.

Inputs.

• Diesel costs £1.83 per litre (Heating Oil £0.79)
• Burning a litre of oil produces about 9.5kWh
• Electricity is £0.28 per kWh, but might rise to £0.48

Before making the comparison, it's important to establish accurately how much electricity is being used. £8 per day is suspiciously high. How was it measured? I think it may be an over-estimate.

Assuming £8 is correct, at 0.28 per unit that's 28.6kWh, equivalent to 3 litres of diesel costing £5.49. Heating oil would cost £2.37, but this assumes a diesel heater can burn heating oil safely and efficiently. Probably OK but I'd be surprised if a youtuber had tested it: a heater run on the wrong oil might spew Carbon Monoxide and unburnt hydrocarbons whilst wasting money.

A running cost of 12p/hour means a diesel oil heater is actually outputting 0.6kw, not '5kw flat out'. 5kWh would cost about £1, not 12p.

A disadvantage of oil heating is that a good percentage of the heat goes up the chimney, whereas electricity keeps it all in the room. How much heat is wasted by an oil heater depends on how the exhaust is arranged. A pipe running around the workshop before leaving the building will do better than one that exits immediately, but long pipes cause other problems.

Nonetheless, oil will cheaper than electricity in the long run. But it's important to understand what the long run is. In order to save money by burning oil, it's necessary to spend money first. The heater and it's power supply have to be bought and installed. The time and money are a dead-loss until the investment has been recovered. I'd guess about £200, which, if Steve's £8 is typical, means he has to spend 25 cold-days in the workshop before oil becomes cheaper. Thereafter, money is slowly saved, but only if the heating is used, and long cold-spells are unusual in the UK.

Northerners tell us they're tough compared with Southerners. Heating a workshop to 20° is too hot for this West Country softie! I run my house heating 5 hours a day at 18°C and don't heat the workshop at all. I prefer to work physically at 12 to 15°C, and usually the lights and machines are enough to take the chill off. But a huge amount depends on how well the workshop is insulated. Snow outside, and mine is at 10°C, not so bad if I dress warmly. Fortunately, I don't have to work in my garden shed – it's below zero.

The easiest way to save money is to turn the thermostat down! Try 18 rather than 20°C

Dave

My exhaust runs a while around the workshop to add radiant heat. I don't have a silencer but the distance helps keep the disturbance to my neighbours down. I discarded the cheap nasty hose clips supplied with it and used better quality ones. At one point I had to take the exhaust near some domestic wiring so I made a top hat bracket to keep it very well clear.

Two CO detectors might sound like overkill but I chose different brands as I figured they might have different thresholds, and different battery lives. One started going off when I was running my stationary engine outside the door the other day so they appear to work!

As mentioned mine was primarily used to seperate the bill from the household bills, it may or may not be any different in price. The exhaust fumes by the time they leave my long exhaust pipe (which has been made to minimise the use of tight radii) as cooler than the air from a hand dryer. The exhaust pipe as it leaves the unit has turned blue with the heat.

• [quote] Electricity is £0.28 per kWh, but might rise to £0.48 [quote]

That sounds like a good price ! We are with Octopus and the charge for electricity is £0.3337 per kWh, plus a daily standing charge of £0.475. (That is 100% from renewable sources, so maybe it costs a bit more).

Are there any issues with fossil burning heaters producing moisture laden warm air, or is the burning flame completely separated from the workshop?

Another happy user of a Chinese 5KW heater for the garage here. I use a 12V 20A power supply to run mine rather than a battery / charger – probably overkill, as I understand the heaters draw around 10A while the glow pin is operating & around an amp when the glow pin switches off, but a 10A PSU at the time wasn't much cheaper than the unit I bought. I went for a component system & built an angle iron frame to hold it and the PSU and fuel it from a 25 litre oil drum, but if I were to do the job again I would go for one of the free-standing cased units with an integral fuel tank that are now available.

A local filling station has a "gas oil" pump which, last time I filled a Jerry can, was around 2/3rds the price of "road" diesel. These heaters will also run on paraffin (some suggestions are that they have less carbon build-up internally when run on paraffin), but I don't have a local supplier of bulk paraffin any more. Contrary to SoD's assertion above, there are many YouTube videos of people experimenting with various fuels for these heaters & they appear to operate on virtually any oil, though (as I understand the current situation) it is illegal to burn anything other than an "approved fuel", which rules out legally using used engine oil as demonstrated by some.

0.1 litres per hour per Kw output seems to be the norm for these heaters (around 0.5 litres per hour for a 5KW unit running flat out).

My exhaust is routed close to the (pressed concrete, mock stone, block) garage wall & exits through a hole drilled through the wall. Noise from the (single silencer) outlet is a low purr when running flat out, with no smoke or smell. I have a glass fibre exhaust wrap to insulate the exhaust run inside the garage (on the "to do" list) just in case anything flammable should fall on the pipe un-noticed – the exhausts, as stated above, run very hot. The heaters are quite noisy on the inside of the garage , though – you can't move large amounts of air with a small-ish fan quietly – but I don't find it objectionably loud.

I also fitted one to my employer's camper van this year & both systems worked without problems "out of the box". So far the Chinese heater has proven more reliable than a 5KW Webasto unit fitted to a motorhome I once owned but, to be fair, the Webasto failure was largely due to an installation error by the motorhome builder. A Webasto unit is over 10 x the cost of the Chinese "clones" & didn't appear (when operating correctly) to be any better or more econonomical. I am toying with the idea of installing one in my current motorhome as a back-up the the installed gas heating system.

I doubt my installation would get my double garage workshop up to 20 degrees from the current "around 0", but it would get it comfortable after an hour or so, which my previous 2KW convection heater could not achieve.

Nigel B.

I have installed one of those cheap Chinese cloned diesel heater in my workshop. When it works, it is very warm and cosy.

However, I have had no end of problems with the fuel pumps sticking and refusing to pump. I have tried three different ones, they run for a few days/ weeks then stick. Not found a reliable way to un-stick them.

The problem may be that Chinese cloned products can come from any number of different factories. Some factories may get the details right while others may not.

Your mileage may differ.

Mike

Edited By mike T on 11/12/2022 12:19:05

I have two write ups on my blog relating to my experiences installing and using one of these heaters.

Heater install

Heater Update

Re pump sticking this may relate to using domestic heating oil rather than diesel fuel. Domestic heating oil has no lubricating oil content and therefore the impulse pump will fail. I use a 60/40 mix and have had no problems.

Alan

I have installed one into my workshop, I found its the best way to heat my workshop, I use a couple of larger tractor battery which is charged with a 210watt solar panel on the workshop roof and a cheap pwd inverter, I also have a 12volt 1000 watt to 230v inverter which I use to run my workshop lights or my lathe/mill lighting (led ones) (not my lathe and mill their 3 phase), and any thing else like cordless drill battery packs etc, their not used all at the same time but does help to keep the bills down for the home management

George

Mike T – it could be the diesel going soapy.

My pump is mounted vertically as recommended and is well wrapped with insulation to try to minimise the ticking noise. I have not insulated the header tank even though the whole assembly is mounted outside albeit fully enclosed (see blog image). The enclosure is a double decked affair with the heater on the lower level. The residual heat from the heater therefore warms the inside of the enclosure with the header tank directly above the heater. The fuel and the pump therefore benefit from protection.

Re vertically mounted pump, on the Eberspacher the pump has to be at an angle to work. Mine is around 60 degrees and works with heating oil and diesel piped up from a floor mounted beer barrel.