Diesel Heater Sand Battery Gas Bottle Waste Exhaust Store Heat Energy Oil Storage Off Grid Van Life

[@mmuller2402]

Maybe a safety guard for the angle grinder would be wise 😂

[@joelalleman9591]

yeah, a co worker of mine had a brand name disc explode and nearly removed half his face !!!!!!!

[@wibble-wo7el]

After all your experiments it might be an idea to strip and check your burn chamber to see if there is any excessive carbon build up or not.

[@DamoMils]

I've had a set up on my heater for a couple of years and it still works perfectly. I used a spare aluminium car intercooler and a couple of car radiator fans on a variable speed controller (running off the 12v supply) blowing through the back of the intercooler into the room. It really does work a treat, the hot air generated is probably about 50% of that of the heater itself and made such a difference in heating the space. I had to mount the intercooler at an angle so that the condensation runs out but may tap a drain in at the lowest point so that it doesn't look like I mounted it on the piss! There were some challenges getting the exhaust split (it is a twin entry and exit intercooler for twin turbos) and adapting to the intercooler inlets but nothing too difficult. If I didn't have that intercooler laying around I'd have used a single turbo version. This will be the 3rd winter for the set up and so far so good. Every time I run it I metaphorically pat myself on the back as it is so effective!

[@WOFFY-qc9te]

DamoMills, you have built a very simple set up which I know recovers a lot of heat, as you point out it is important to drain condensate especially if your heat exchanger is aluminium as the condensate is acidic. There is a lot of tosh talked about recovering the exhaust heat but providing the AF ratio is not compromised by flow restriction and the condensate is drained it really does not matter how much heat you extract. You can adjust the AF in the setup but I find the diesel heaters can become a bit unstable at high outputs as the AF algorithm used for the controller is linear and this tends to lean the mixture when flat out when the base setting are optimal, mine 12kW runs at 70% for best economy for my use.. Even sending the exhaust into the top of a domestic convector radiator discharging at the lower point can make a great addition to a workshop space. Avoid using the corrugated pipe if possible as this does impede flow compared with smooth bore. Best

[@Handle_gravel]

this is the way high efficiency central furnaces work. Pipe in outdoor air for combustion and you've done the most reasonable efficiency upgrades. There's a reason they call the second "heat recovery" stage a condenser. They extract so much heat, that 90%+ efficiency furnaces can run PVC as the flue pipe.

[@WOFFY-qc9te]

​@@Handle_gravel There is misunderstanding about flue temperature and I think it comes from people confusing forced draft with an open fire or log burner chimney where incomplete combustion is present with high level of particulates, providing combustion is complete you can recover a high percentage of residual heat without 'sooting' . You are correct in pointing out PVC pipe being used for exhaust gases. Ships use "economisers" on the exhaust to pre heat boiler feed water. Another point is that a condensing boiler becomes inefficient when above 75 % burn rate this is because the flue temperature is so high condensing and heat recovery fall off. So running your boiler at a lower temperature keeps allows the recovery of residual heat to be transferred for combustion.

[@DamoMils]

@@WOFFY-qc9te Yes you're right. I haven't messed with the AF ratio as wanted to see how it performed before doing do. Intercoolers are designed for high flow rates and much as there is nothing like the same flow from the heater there seemingly doesn't seems to be any more restriction than the standard exhaust provides - although I'm not sure how I'd measure this to be honest! I had thought the same as you about the exhaust being corrugated and think that I'll simply make it copper pipe for the short run to the intercooler and out of it to the outside.

[@WOFFY-qc9te]

​@@DamoMils Hello, AF (Air fuel) ratio on these heaters is not a closed loop i e it is not monitored. The temperature probes are for over temp and ambient temperature required so ignore those. Assuming you heater has five levels of heat. so for low heat 1 pulse per second (fuel flow / heat )on the pump 1pps and for flat out 5pps. Air fuel (AF) is set by the fan speed for each of these levels and that is a linear line from the slowest speed to the highest speed. Unfortunately the air flow not linear (especially if there is additional pipework) so if the heater is at optimum AF ratio at 1 it may not be at 5. How to correct; in the settings you have a low fans peed and a high an speed this is our AF line which we may have to tilt to find the sweet AF for our favoured heating level. If rich at heating level 5 then increase 'fan maximum speed' (keep below 5800 rpm or motor fan maybe unhappy. same at low heating level. If lean do the reverse. Suggest you draw this : vertical line = fan speed, horizontal line = pump pulse, draw your line. Noting the performance of the unit move the line (fan speed) up to lean down to richen, you will see and smell this in the exhaust and fuel consumption. You can make a note of your output temperature on this line. There should be zero soot in the exhaust if burning Kerosene, A1 jet fuel and good diesel. Bio diesel. If you burn engine oil or other contaminated oils you will carbon up the combustion tube which is a bugger to clean as it has a screen hidden behind the riveted plate. The vaporising screen in the glow plug hole is easily cleaned or replaced Finally these heaters are are best run at < 75 % of there maximum chooch, the slight increase in heat output above 75% is not worth the noise of wear on the unit in fact running the heater longer at a lower level is more fuel efficient and it ideal if using the exhaust to heat water in a cylinder or a secondary heat recovery from the exhaust, this is basic thermodynamics. Very important that the condensate is drained off. Also always have a CO monitor handy and clamp your exhaust fittings in addition ensure the janky fuel connections in the unit are sound as Quality Control and Chinese do not go in the same sentence. Note your gas condensing boiler becomes less efficient above 75% as it is too hot to recover all latent heat from the exhaust. Run your boiler at a lower flow temp for longer time rather than the reverse. Drawing hot water will run the boiler above its optimum condensing profile. Your intercooler is not going to effect flow as you have it so you should look at optimising AF

[@aarongunner1711]

Could try the same setup, But with another tighter coil in the centre of the sand battery. for the intake air for the heater. Will act as a heat recovery system. The lost heat from the exhaust then preheats the intake. Its a Common method on coal/gas fired steam power stations.

[@carld3184]

Nice work Andy, I like the sand for capturing the exhaust heat instead of using water or engine antifreeze. My only suggestion is to raise the sand bottle a bit so that the exhaust pipe is always sloping down towards the outlet.

[@tullgutten]

I would try to keep the exhaust above 100°C and see that it doesn't get wet in the pipe after it has run for about 30 or 60 minutes. And when capturing the exhaust heat you must be more careful about not having short runs but always get it fully warmed and preferably no less than 30 minute run time

[@cerealtiller]

The Exhaust gases should exit the Heater unrestricted and Hot this Setup will cause rapid Sooting and an unstable Flame.

[@victorkrivor2174]

looks like there is about 2 feet of piping from the exhaust header to the tank, should be plenty of space to let the hot exhaust remain hot

[@cerealtiller]

@@victorkrivor2174 The Gases should still be Hot as the leave the end of the Exhaust tubing. if not their temperature will reach 'Dewpoint' which will cause incomplete Combustion and Rapid sooting. there should be no more than 270 or so of Bends in the Pipework. and the Intake for combustion Hose should draw Air from the same Plane as the Exhaust Exits to. If not a Gust of Wind could Extinguish the Flame within the Heater.

[@timderks5960]

​@@cerealtiller Your comment makes absolutely no sense. The temperature of exhaust gasses has nothing to do with complete or incomplete combustion. Hell, most central heating systems in the Netherlands literally use their exhaust gasses to pre-heat the incoming air. Also, a flame in a diesel heater is not gonna get extinguished by a gust of air, it's not a candle...

[@cerealtiller]

@@timderks5960 Have Installed and repaired several Hundred Combustion heaters over the Decade Diesel Fuelled types had to have a Hot and unrestricted gas Exit preferably with a Balanced Combustion Air intake. have seen the flame Fail in Windy conditions.

[@aluminiumsloep]

So in Eastern Europe many people used coal stoves with massive stone walls basically a stone battery. I don't know the name in english for the stone but in Dutch its called "speksteen"., So basically a sand/stone battery is an ancient method. In Poland i saw 2,5 meter high stoves 1,5 wide and 1,5 depth while in the side the burn chamber for the coals was actually quite small... Same principle. Also go to the coast see how warm basalt stays long after sundown... Stone is denser and stores heat for longer i think... So maybe a combination will work? Basalt block in middle sand around where exhoust pipe is... good work keep it up.. Now maybe i need to design a good looking aluminium casing about 2 meters high incorporate the heater inside and sand all filled into the aluminium sculpture... Stoves can be good looking guys......example: "bullerjan stove"....

[@declanmurphy5618]

My misuse is from Estonia and your 100% correct about the chambered walls storage

[@HomesteadFrance]

Set the pipe into the floor and/or wall?

[@cozzy206]

Nice one Andy thanks 😉

[@andyking05]

The exhaust needs to be in a constant downward direction, to much restriction will soot up the heater tho, wider pipe after the first meter of exhaust maybe, poor a thermometer in the sand, run the inlet air through the sand, or a separate loop to a little radiator inside

[@andyfireblade]

thanks for your comment andy

[@WOFFY-qc9te]

The a low exhaust (flue ) temperature is undesirable if particulates are present or the products of combustion which may lead to the formation of creosotes this is mainly true for log burners or over fuelled turbocharged diesel engines. Providing the air flow is not reducing the air to fuel ratio and creating back pressure ( which in the example shown is not ) the addition of an "economiser ' (a vessel or device to recover residual heat form a boiler or steam system ) will make no difference. However it is very important to ensure the condensate does not accumulate at the lowest point as this will impede combustion by restricting air flow through the system. It is acidic and should be discharged to a drain. I have a 220 ltr solar tank which is preheated by the exhaust from a similar diesel heater and I have had no problems with combustion whatsoever. Initially I thought a FD fan my be needed but this was not the case as the heater managed to supply enough air through the 3 meters of 22mm (smooth bore) heat exchanger to maintain constant flame and good combustion as measured by lamda the AF is 14.5:1 - 16.5:1 depending on fuel and operating detla T through the lower coil > 16 C < 45 C preheating the solar store or immersion. Further; I have used a 20 plate heat exchanger to some effect , directly transferring exhaust heat into a pressurised HW system and heating circuit although the later requires some cooperation from the boiler pump. .

[@madforit9661]

Glad I came across your vids I am the same, thinking what a waste of heat from the exhaust We need to use it before it goes out. I thought the radiator was good idea. Do you not think that's worth doing. I have a koi pond, I was thinking if you inserted most of the exhaust in water . For example I have the filters all ground level, put it in the filter and have the exhaust out the wall . Would this work heating up the water? It's hard to explain how I am thinking but basically the exhaust as a water heater

[@andyfireblade]

great idea cheers andy, please take a look at my other videos

[@Robbieminty]

Andy How about you ditch the sand. Using a small fish tank pump introduce air into bottom of chamber and then have an outlet pipe near the top to allow the hot air out. Would work at relatively low pressure and you can guide the air flow. You would probably have to weld the top back onto the gas bottle to keep it all sealed

[@Bob.Jenkins]

You don't want to heat the outside of the Gas bottle - that'd be pointless, as you want to store heat and slowly bleed it into the environment. Ensure that the exhaust coil *doesn't' touch the Gas bottles side so that heat has to transfer through the sand and then into the Gas bottles metal.

[@andyfireblade]

good comment

[@wheredidileavemycell]

can you try coolant?

[@paulmullane9662]

Great idea take the guard off your grinder…….bye bye eyes

[@andyfireblade]

Good tip!

[@LostDeadSoul]

If you'd have 10KG of sand, increasing the temp from 20°C to 120°C you'd have an energy capacity og 830.000 joules. Compared to 40.000.000 for 1KG of oil. At best you'll get 2% increase in effectivity. Your usable delta temp only get worse as things heat up. Sorry mate.

[@VinoVeritas_]

Do you know what Specific Heat Capacity is?

[@andyfireblade]

no sorry , i will try to find out cheers andy

[@itsumonihon]

This will likely stop functioning with a few days worth of use. The condensation and carbon buildup in the coil and at the base of the sand battery will cause the exhaust to clog up. The heater will no longer start easily and may just stop working entirely. You need to design the lowest point of the exhaust so that it's outdoors and so that liquids and carbon debris can be blown out and down. Your current outlet pipe is going to be full of crud around the area where it meets the sand battery. You will hear this - your heater will start "groaning" almost like a jet engine or ghoul on startup when there's moisture in the exhaust impeding startup.

[@andyfireblade]

thanks for your input cheers andy

[@sidknowles3467]

@@andyfireblade I have the same setup with the heater over the top of the bottle been running for over a year now with no problems keeps my workshop warm all night in winter.