Will the new heater thermosiphon? Well, umm, no. Here is the link for the heater I bought. I am not affiliated with the manufacturer and receive nothing for sharing this link. www.alibaba.com/product-detai...
To answer your question at the end: It took 1200 seconds (20 minutes) to heat 10000cm2 (10L) of water 33 degrees (from 17 to 50). That is 330000 calories in 20 minutes, given the specific energy of water (4.18) that equals 1379400 joules in 1200 seconds, so 1149,5 joules in one second. Since a joule equals 1Ws, we can strike out the seconds and there you have it. The power transfered into the water was 1149,5W (on average, it was probably more when the water was colder and becoming less when the water heated up)
If you rotate the heating unit so the cold side water input it slightly lower then the hot side output you might be able to get enough convection to circulate the water.
Thermosiphons always benefit from increasing the vertical height differences. I realize it was done this way to keep the shot compact, but it is close to the worst layout for a thermosiphon. You are attempting a closed-loop version of the *stack effect* so the siphon force _increases endlessly with height_ until the point where fluid flow friction overwhelms the stack effect. That flow concern also means you should use large diameter tubing/pipes, and keep things like the jug's petcock out of the flow loop. Also, some layouts will not self-start, but will work once something gets an initial flow established. en.wikipedia.org/wiki/Stack_effect
Would love to see what kind of heating time you get (under equivalent conditions) with a combined system that includes your exhaust heat recovery thing. That being said, if I were out camping in the bush I wouldn't mind waiting 20-30 minutes for a batch of hot showering water. There's always plenty of camp chores to fill the time!
A side by side comparison would be good. To see if the internal water heater or egr heater generates heat quickest. This would show if the extra expense for the inbuilt water heater is worth it.
Please do a test with your EGR cooler & pump to get maximum efficiency, looks like a setup I would like to use for a van build. Great test, thx for the clips!
I appreciate your efforts and time testing. I was expecting a larger rise in temp of the water jug. Considering the run time of the heater to raise the ambient air temps, I don't see the heater running longer than 20 mins at a time. Meaning you couldn't heat a large volume of coolant. Over the same period of time using the coolant pump, could you obtain a higher temp in your jug with the EGR cooler on the exhaust gas? Thanks again
Interesting, would like to see follow up experiment like this: 1) Use the diesel water&air heater to pre-heat the water 2) use egr cooler on the exhaust output directly under the heater to further heat the water. 3) put the heater on max 5 setting from start, not 3. Always possible to turn down the heat later :)
Put the hot water return at the bottom and the cold outlet at the top. The hot water rising from the bottom will cycle the cold water through the heater. For this to work you'll also need the system to be full of water obviously, or at least have both hoses under the water line inside the tank.
With the inlet and outlet pointing down?? how would it run if the heater was set up on one side as can be done with glow plug at top? Just a thought,, good video Thanks
Hi Daved, I have used this same system using a small log burner in my workshop with great results I think for it to Thermosiphon efficiently you need the water in the "jug" to be lower than the feed pipe coming from the heater, otherwise you are adding pressure that will hold back the rising heat. Reduce the amount of water below the pipe and I bet you will get it to circulate, ..."RETEST"...
Capturing the heat from the exhaust from these units definitely seems like the way to go. I feel like a majority of the heat is lost to the exhaust, watching a bunch of different videos of the internals of these heaters shows that there really is not that much surface area in the combustion chamber.
I'm not sure if it's the issue but I saw another video of a gentleman making a diy heat exchanger his first prototype had a very similar issue. The boiling water should build pressure but not with both ends open. He had a term for it but a one way valve on the supply fixed this and pushed water through the outlet. I would love to see if this creates thermosiphon!
Great video's, have you figured out the maximum hot water temp that can be reached, say even in 50 litres of water, even if time constraints were not important?
Depending on the water heatex design, it might siphon if the heater is mounted sideways. Basically the line from the heat source must only travel upwards to siphon.
Try to put a check valve on inlet side of heater line. Also, maybe seal off tank a bit, so steam pressure pushes water to cycle. Of course add a pressure relief for safety.
Ok I bought the all metal 8kw with remote. I noticed that over time a build up in the burn chamber is there. Question?; is there a product that could be ran though to get rid of it like acetone, laquar thinner, paint thinner, napalm?
40-42c is the perfect temp for having a shower, so if you turned it on in the morning inside your camper van, make a cup of tea and after 20min turn the water pump off and then have a separate pump to a shower head and taps you can enjoy a lovely hot shower.
Well, with the water inlet/outlet on the bottom, did you flip the heater over, to purge all the air from it? Otherwise it might expand the air when hot & prevent any real flow.
I don't think the pipes going down first is an issue (other than creating a small height difference between them), its all about pressure difference. It doesn't matter where the pipes go, just where they end up. Think of siphoning a liquid out of a container using a hose, it goes up first but still works. What will matter much more is the height difference between the heater and the tank, the pressure difference between the water inlet and outlet of the heater should be proportional to this height difference. And flow rate will be proportional to this pressure difference (possibly not a linear relationship?).
Hey there David can you run a basic experiment on a regular heater running some copper tubing through fins to see if it can heater water while running or something similar maybe even thermosiphon ?
In Philadelphia, I interned for a retrofitter of gas and heating oil burners in college. He was on a first name basis was Mr. Beckett of Beckett oil burners in Elyria, Ohio. Basically, diesel/heating oil heats faster than electricity or natural gas. Propane was even slower than natural gas based on the BTU's per Cubic Foot or Cubic Meter. Laugh! The owner would fly all over the country, USA, doing seminars on retrofitting, but refused to think a VCR tape would help. Of course, now we have gone beyond VCR tapes and DVD's to RU-vid videos!
I am curious iff you put the EGR in line what the water temp rising will be. But the thing that i am most curious about is when you dont pump water for a longer time. Will the steam pressure be high? So will it boil the shit out of the EGR cooler and heater water system. Witch is more efficient on it's own the heater and water combo or a separate 5KW heater and the EGR cooler. I am building a stealth camper van within a year and looking to use this heater for shower water maybe. Greetz from holland!
So it looks like it heats as fast as my little hot water tank which has a 600w immersion heater or 1200w gas heater - so somewhere midway around 900 watts perhaps 1kw allowing for pipe losses
Is there a way to turn the fan speed down or off but still have the heater running. Have a water pump pushing water through to heat up the tank. That would be great if you disnt need to run the fan for air heater at the same time?
@@DavidMcLuckie yes I have picked that up after watching more videos. Its seems you just want to turn your water pump on whenever you run the heater. Then just have the water circulate back to the tank. I've watched so many videos now I'm not sure what one I'm commenting now
This is the first video I have seen of yours where I saw your face. I kind of enjoyed the mystery. I used to imagine you're a crazy scotsman inventor type.
Wouldnt it be cool to set up and run 2 water systems at the same time, 1 heated by the heater, 2 heated by egr cooler and see which works better. My money is on the egr cooler.
I have a question so does this have to continuously run to keep the coolant warm........ Like for instance would you be in let's say your truck's bunk trying to sleep in the fiery pits of hell why'll still trying to keep your engine coolant warm....... If that is the case I think it would be better off installing two separate systems.
Yes. You have correctly identified one of the major drawbacks with this version. I'm sure others would suggest opening a window, but that's just wasting heat and fuel.
Pipes on heater facing up and use at full power please. I think we need a couple of these bad boys working in tandem for the RV winter scene. One for water and air and one switchable between water and engine and also supplying air to the cab????
I may have a solution for the thermosyphon malfunction. (As described about 2:30 in the video.) I'm drawing on my experience as a retired plumber who has also worked with pumps and thermosiphoning solar heating systems. I think what has happened in your thermosiphoning setup is the water reaches a boiling point and so increases the pressure in the system to the point where the pressure is pushing the water in the cold side of the system back into the tank. The simple solution would be to install a check valve on the cold side tubing, preferably one that has minimal restriction to flow.
Hi David I had a thought for a video. What about using a turbo intercooler connected to the exhaust with a fan to extract heat. If it works without messing with the air flow, you could put a thermocouple and arduino to control the fan based on heat. Also I seen a water cooler intercooler could be used to extract heat from the heated water. If you wanted
@David McLuckie are these any good for a boat for hot water in a sink. I'm looking for a alternative rather than a gas geyser. Also to keep it warm. Does the heater have a thermostat on it so when your just using the heater without running the water. So the water doesn't boil over
Hey David, been looking for one of those white variable voltage supplies you have in the background. I can't find one any higher than 30v/10amp. Don't these heaters draw more than 10 amps at the beginning when firing up?
Most of the ones I've tried pull just on or just under 10A which is why I picked that power supply. If you find one with more power let me know as I've been looking as well. :)
if you connected the hoses internally by dropping a coil of copper into the water tank (soft 22mm) will give you the circulation you need the silicone hoses should take up the expansion.
About your last question, the calculation is very simple: 10 liters of water need 10x4.2KJ to heat up one degree. That times 33° increase means 1386KJ in 20 minutes. That means 1155 Joules per second, that means 1155W of heat power (average). Equivalent to a 1000W electric heater approximately.
1155w....... thats a lot of heat to save from the exhaust and this isnt 100 o/o efficient so normally it must exhaust an insane ammount of heat outside..... it makes sense to get as much heat as possible from the exhaust gasses
@@freewheelinfranklyn Actually that gas has a very low density and a very low pressure. Because of the high temperature. So, it does not contain a huge quantity of heat. Of course, it could be harnessed increasing the efficiency of the system. But one shouldn't expect too much from it.
I calculated that the amount of heat you get in the water is 0.47kWh at full blast. Now this is a bit less than the exhaust heat of 0.5-0.7kWh typical. If you let the exhaust heat go through a BPHE in this way - exhaust pipe going vertically into a bucket/tank/barrel/water butt, then goes into a BPHE vertically, then the other outlet of BPHE coming out of the bucket horizontally or 10 degrees slope to drip out condensation naturally. The whole set up looks like a big L shape inside the tank, do you get it? In that way, you won't even need a pump. A true thermocycle will happen because the heat source itself is inside the tank.
The air flowing over the heat exchanger for the blown heating helps to regulate the units temperature but you may not water continuous hot water so if no water is flowing around this part would the unit overheat and would you need to drain water to stop it from turning to steam which could pressurize your water tank if not vented
@@andrewbartleman9169 That is what i suspected as I have heard that if the power is cut to these so stopping the fan they can overheat even thought it switches the burn off to they need a cool down period before stopping completely
need a back flow ball valve . like in your coffee maker. then it might circulate. the heated water can only escape out one pipe,sucking cool water in the other. like a coffee maker.
So....what's the point of this thing? Intriguing as it is. It seems that it can't heat air only if it's plumbed into a water circuit. Without the pump it will lock and splutter. So how do you see it being put to use? Cheers :)
@@DavidGalle1 @thomas barlow I was asking myself the same question, is the flew of the water going out enough hot to handle a 2L/mn flew of water for showering?
How about an air box with a copper coil on the outlet of the heater with the hot water outlet plumbed through it back to the top of the tank? You could also run the heater exhaust through a copper coil in the tank. Its all waste heat waiting to be captured.
What functions does the control panel have? Will it turn the pump on? Does it allow you to run it without the blower running? Example radiant floor heat without forced air? If you were to run liquid only would it be thermostatically controlled? If you had it hooked up to water and ran it in forced air mode without pumping water, would this damage the unit? My idea would be to use it in a van for both Forced air heat and or radiant floor heat, one, the other or both simultaneously
Heater on and off, heater output level 1-5 and pump on off control. The fan that blows the hot air is on the same motor as the fan that supplies forced air into the burn chamber. So it cannot be turned off. Without the pump running it'll happily boil whatever is in the heat exchanger.
The best way I have seen for people using these heaters in a camper. Is using a outboard motor fuel tank. Because hose detaches so you can fill the tank at the gas station. Not trying to fill the little tank on the heater in the camper / van.
I like what you are doing on your channel here in pennsylvania we call it tinkering around But I'm having a hard time understanding what saying It's just your accent sorry I do like the channel
1440p@25 is very nice as I don't actually have to force my phone to use 1440p it does it on its own on 25fps (1440p60 requires a lot of bandwidth and my phone doesn't think my WiFi or 4g is fast enough on 60fps)
im curious to know how many liters a minute is that water pump. plus how hot is the water coming out of that outlet tube after its heated. so example if i just attach a shower head to it.
I think that pump is 10L per minute. I worked it out that the heat exchanger is heating the water with about 500W of energy. So either a cold shower with good water flow, or a hot shower with little water flow.
I would use this unit in my campervan it would be the source of Heat and the hot water heater to run the faucet with hot-water and a shower with hot water
@@anythingthatmoves9609 the only dilemma that I would have would be in the summer time when it's a hundred degrees and I'm trying to keep the van cool I would have to divert the hot-air outside I was fixing to buy the diesel heater for the van I might wait and buy one of these one unit that does two things in a camper van storage and room for stuff in my van is limited
Hi David. Don’t think that this one will work in any situation other than as a overnight camper van heater with a hot water storage tank/ callorifier. Cheers Jim. (Spelling bad).
