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Chinese diesel heater questions

Billybobthethird

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Hello, I bought a vevor heater, and it's mechanically totaled out of the box. I was able to get it to make heat by manually priming it, and besides leaking smoke from every joint in the exhaust and muffler, it did make heat for a couple hours, but not much. After only maybe 4 hours of making only enough heat to make a 6x12 trailer 55 f in 20 degree weather, it stopped. I took it apart today to see if I could make it sort of work to defrost my snowblower again, and both gaskets stuck and tore, which seem abnormal from videos I've seen of people taking apart these heaters, and the whole burner was packed with soot. I do have an extended exhaust on it to recover some of the exhaust heat, but is there a limit to how long this can be? was it the fact that the exhaust was so leaky maybe a contributing factor? thank you for your replies.
 
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Ok, I play with these a lot so let me jump in.

The biggest issues I've ever had was from messing up my exhaust pipes and running it at low loads. If it's making visible smoke then you're not getting complete combustion and either it's not getting fuel correctly, or it's too cold. You'll want to get it up to full power right out the gate, it defaults to H3 on startup, so kick it up to H6 as soon as it starts lighting off. Once the heater gets to a clean burn the smoke should be invisible.

In the muffler is a small hole in the side, make sure that's the lowest point in the exhaust so condensate can drain. If that pipe can't drain it'll fill with water and choke out the system.

The other issue I've had was running at low loads for extended periods of time. I find that kicking it up to H6 (max) for 20 minutes or so every day really makes it run better and helps keep the burn chamber clean.

The clamps that come with the kit are adequate at best, replace those and it'll help the airflow.

The gaskets tend to stick, I ended up using red RTV on my cleanings before I could source replacement kits. Fortunately the gasket/screen kits are cheap and relatively easy to get on Amazon nowadays.

The atomizer screen and housing need to be cleaned as part of the service. There is a small hole in the screen housing that needs to be cleaned well and the screen needs to be seated all the way into its hole.

Skip the EGR for now until you get the system running and cleaned, then make sure the EGR allows good downward airflow to prevent condensate.

You can see my cleaning guide I wrote up a few years ago, feel free to keep a few copies. Feel free to ask me any more questions. I love these things. ? Keep in mind those directions were written before I had rebuild kits so disregard the excess RTV.

Another thing I did when I installed the 2nd one in my cabin was to get a 3rd unit, a small tool box, and built a tool kit with the tools for opening it up. If one clogs up it's a real quick exchange to a cleaned one and you can get the heat back on while the clogged one gets cleaned and put back in the toolbox. Buying the heaters directly from Vevor.com saves a good chunk of money.
 
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I'm not using EGR, I'm using a longer pipe. The joints were leaking, but most of the smoke came from every part of the muffler. I only ran it on h6, as I was defrosting a snowblower, so more heat was more better. The longer pipe is necessary because of where the exhaust leaves the trailer at this point, because I didn't think it would cause issues. I don't know if my issues are further issues with the faulty controller, or with the exhaust at this point, though. I was going to try it tomorrow with only the one pipe, though, to eliminate the colander of a muffler
 
Are you using the hard plastic fuel lines? If you're using soft rubber lines, then the pump can struggle to provide proper fuel flow.

The exhaust pipe should have no more than 90 degrees of total bend in it. i.e. two 45 degree bends = 90 degrees. Also, there should be no upward slope at any point in the exhaust pipe routing.

There's a Fakebook group that is a wealth of knowledge about how to install and run these.
 
ok, so then that explains why it plugged up. It's a shame the exhaust is such a picky thing given the use I'm needing it for. why would it matter if the exhaust goes up? hot air rises
 
ok, so then that explains why it plugged up. It's a shame the exhaust is such a picky thing given the use I'm needing it for. why would it matter if the exhaust goes up? hot air rises
Because the hot exhaust has water vapor in it and once that hot wet air gets to the pipe and starts condensing the water gets forced out. The water needs somewhere to go or it just fills up the pipe at the lowest point.

I know I've got that problem with my master bedroom heater at camp and getting pipe -> muffler -> pipe -> pipe to flow right and not back up took some fenagling. Once I got my clamps in the right place though and had that weep hole at the bottom of the long loop it ran like a champ.
 
Because the hot exhaust has water vapor in it and once that hot wet air gets to the pipe and starts condensing the water gets forced out. The water needs somewhere to go or it just fills up the pipe at the lowest point.

I know I've got that problem with my master bedroom heater at camp and getting pipe -> muffler -> pipe -> pipe to flow right and not back up took some fenagling. Once I got my clamps in the right place though and had that weep hole at the bottom of the long loop it ran like a champ.
Well phooey

I just bought one- the cheaper erector set model- and a 6’6” exhaust to run out (up) an existing B-vent in my office trailer aka shop.

And now you tell me that won’t work:(
 
Well phooey

I just bought one- the cheaper erector set model- and a 6’6” exhaust to run out (up) an existing B-vent in my office trailer aka shop.

And now you tell me that won’t work:(
It will, the one in my master bedroom has about 9ft of total pipe on it. The trick is the muffler hole. Let me do a quick krappy MSPaint sketch...

diesel exhaust.jpg
On one edge of the muffler is a small hole. As long as that hole is at the lowest point in the system, like in the first figure, it'll work just fine. That's how I had to adjust my MBR heater.

If the hole ISN'T at the very bottom, like in the second picture, the water pools at the lowest point in the loop and fills the exhaust pipe, ala bandanna in the tailpipe, and your exhaust gas can't drain out until it gets high enough to find a hole, by which time the poor heater has choked and whined and smoked out the neighborhood.

Obviously the best option if you can do it is to have a constant downward slope on the whole pipe, but that's not always an option.

Does that help?

Oh, and as for the cheaper "erector set" model? I always prefer those for a few reasons. First, the pre-builts you still have to do the intake and exhaust plumbing in and they leave jjjuuussssttt barely enough space at the bottom to do that... if you're careful... yeah. The second reason I like the kits is that you can put your controller out wherever you want it to be instead of right in front of the hot pipe where you'll never get accurate readings. Many of the 5Kw units you can actually set for a temperature and it will ramp up and down as needed, but having the thermostat right next to the hottest air isn't exactly accurate. Third reason is more flexibility for the fuel tank. You can mount it on the wall on the other side of a door, mount the tank outside and the heater inside, just skip it and drop the fuel pickup into a 5Gal jug, whatever you want to do. Those are just my top 2 reasons anyways. ;)
 
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A couple more things for ya.

First, go ahead and grab yourself a copy of my Diesel Heater Cleaning Guide and see what all is entailed in servicing one of those heaters. Be aware that when I wrote that you couldn't get a service kit from amazon for it so please disregard all the red RTV on there.

The ticking on the pump will drive you nuts, grab a case for the pump and make sure the pump is mounted at about a 30deg angle with the outlet pointing up.

If you don't have a plan on how to get the exhaust pipe out the wall yet, many people use a marine penetration.
 
I bought 8kW aka ~26,000btu

So I’ll have to put a bucket under the thing before I run it vertically out the B-vent. I actually don’t think it’s B-vent, it’s double-wall kerosene pipe with the outer pipe being air intake.
I was going to make a bracket to center the exhaust pipe and then stuff around the diesel heater exhaust with fiberglass batting to keep it from being a cold air intake vent.
Was also going to gravity filter some waste waste oil, cut it 50% with kero, and blend the supply side with #2 attempting to run 25% #2 and 75% waste oil/kerosene. Not sure if that’s a good idea but I make a few gallons of waste oil every 3-4 months.

Thanks for the tips
 
Was also going to gravity filter some waste waste oil, cut it 50% with kero, and blend the supply side with #2 attempting to run 25% #2 and 75% waste oil/kerosene. Not sure if that’s a good idea but I make a few gallons of waste oil every 3-4 months.
You'll have to clean it more often and you might need to keep an eye on bitumen deposits in the exhaust pipe if they start clogging up that drip hole, so get a couple extra mufflers so you can swap them out and clean them if needed.

I was going to make a bracket to center the exhaust pipe and then stuff around the diesel heater exhaust with fiberglass batting to keep it from being a cold air intake vent.
That'll work, but use rock wool as it handles the heat better than the fiberglass which will just melt and/or smolder if it gets too hot.

So I’ll have to put a bucket under the thing before I run it vertically out the B-vent. I actually don’t think it’s B-vent, it’s double-wall kerosene pipe with the outer pipe being air intake.
Fortunately unless it's really humid inside, there isn't that much that comes out once it's fully warmed up and going. Most of the condensation happens and pools up while it's still getting up to a clean burn.
 
use rock wool as it handles the heat better than the fiberglass which will just melt and/or smolder if it gets too hot
If glass fiber starts smoldering holy cow I’d think I’ll have worse problems already ?
 
ok, so then that explains why it plugged up. It's a shame the exhaust is such a picky thing given the use I'm needing it for. why would it matter if the exhaust goes up? hot air rises
Keep in mind this…
Hot air does not rise on its own…
It is PUSHED UP by dense cold air.
In an exhaust pipe there is no cold air. Only the exhaust. So in a sealed combustion setup like his, hot air can only move from the force of the flame pushing on it. If the pipe slopes down, moisture and the exhaust gasses will be pushed along with gravity.
 
Ok, I play with these a lot so let me jump in.
Hey man, you seem really experienced with these chinese diesel heaters so i was hoping i could get some answers from you !
I am installing one of these heaters in my sailboat and i've understood it that the muffler that comes with it is only for outdoor use, that it is not "air tight". But in a sailboat you cant really put the muffler on the outside, however i am able to mount the heater over the exhaust outlet so the exhaust is pointed downwards, in other words i would not really need to muffler no?
I would love your input on if you think running one of these mufflers inside is dangerous or you think it would be fine? Because of course i would love to have the muffler on, just dont wanna make the air inside dangerous.
I know there is air tight mufflers to buy but they seem soo over expensive
Maybe i just have the muffler inside and get a co reader ..
 
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There's no need for the muffler if the exhaust pipe is always going down, it just helps with the noise a bit and provides that drain hole for the initial start up. If you're doing this in a boat there are penetrations made for getting the exhaust through the hull. They're pretty cheap.

NEVER HAVE YOUR EXHAUST DUMP INTO THE CABIN!!!!

A Co meter is a must have. Is the risk not worth the $20?

In a perfect world the heater would be mounted in your engine compartment or other uninhabited space, air duct to the cabin, and exhaust through the hull outside.
 
In a perfect world the heater would be mounted in your engine compartment or other uninhabited space, air duct to the cabin, and exhaust through the hull outside.
Drip loop and ‘muffler’ in the locker, exhaust run high on a sheer. Engine bays are generally ventilated, too.
 
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