Woes replacing diesel heater with Chinese one

TobyQuest

TobyQuest

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Hello,

My new diesel heater has E8 error and fuel is not getting pumped into it even though the pump is clicking and attempting to....can anyone help:

Backstory:

As my old Mikuni MY16 diesel heater had an issue it was cheaper to replace it than fix it.
I bought a 5kw Vevor chinese one and want to run it from my main diesel fuel tank. Also I saw people saying this rubbery green hose they supply you with is not very good and its better to use the hard nylon hose that has a smaller bore hole because the fuel pump finds it easier to push the fuel through.
diesel.jpg


So I thought i would be clever and simply take the higher quality nylon hose off my old heater and plug it onto the new one. The metal ends of the fuel pump were larger on my new heater so i ran a length of green hose over that and the nylon one. I have many areas of air inside the hose which I can see, but the pump is clicking but still not pumping the fuel through, lik its too weak, or maybe theres a blockage, but im just making guesses.
To what extent are these chinese heaters gravity-fed? The current set up ive installed takes the diesel by splicing from the main fuel line which runs on the top of the fuel tank, so I dont have a line that goes down inside the tank so to speak. It worked fine on the old diesel heater. Thats how they installed it.

How to remove the air bubbles?
 
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My Chinese heater (in my workshop) has the wired remote fitted to it and it has a "prime" function on it to get the fuel through initially, does yours have this option ?
Another thing, if your hose is clear, can you see the bubbles and are they moving towards the heater or just "pulsing" in more or less the same piece of pipe ?
Finally, can you mount the pump lower than the tank as this may help things ?
And dont forget to mount the pump on the diagonal with the feed end pointing up, as if they are horizontal or nose down, any trapped air in the pump becomes imprisoned and hinders the pumping action and will also wear out the pump prematurely.
 
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Just because the pump is 'clicking' doesn't mean it is pumping. I removed one yesterday that was bone dry although fuel was right oup to the pump inlket. The little ball in pump was stuck but easily cleared using a high pressure airline. replaced & works well now.

You do also have the pump orientated correctly with the outlet pointing above horizontal towards 'up'?
 
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The instructions weren't the best. But I've got it angled at 35 to 45 degrees with the end that the electrical plug is on being at the higher end and I'm presuming that's the outlet from the pump and have arranged it a so.

One other thing to mention is that my old fuel pump was on the opposite side of the van to the diesel heater. The electrical cable supplied was only about a metre long and wouldn't reach so i cut the end of and added about 2m of cable and then stuck the plug back on and put the new fuel pump over on that side.
Would the lengthening of the fuel pump power cable have created an issue that is now weaker?

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TobyQuest said:
The instructions weren't the best. But I've got it angled at 35 to 45 degrees with the end that the electrical plug is on being at the higher end and I'm presuming that's the outlet from the pump and have arranged it a so.

One other thing to mention is that my old fuel pump was on the opposite side of the van to the diesel heater. The electrical cable supplied was only about a metre long and wouldn't reach so i cut the end of and added about 2m of cable and then stuck the plug back on and put the new fuel pump over on that side.
Would the lengthening of the fuel pump power cable have created an issue that is now weaker?
Click to expand...

No, I extended mine about the same and my pump happily pumping away and your pump is the correct way around. (y)

Is your fuel line the 4mm hard plastic type or the bigger diameter soft maybe green type?
 
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It's predominantly the small nylon one, except in one place is about 15cm of the green larger one
 
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jockaneezer yes spot on the bubbles are just pulsing. They go a few mm one way, then seem to go back again right after
 
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If you have a long run of fuel line as I have, then I disconnected the fuel line at the heater and used a syringe to suck the fuel through to the heater as air is compressible and a lot of air in the fuel line leading up to the heater gives the pump a hard time trying to push the fuel through. Once the fuel is at the heater, then use the priming feature to get fuel into the heater itself, but don't go too mad with the priming or you will flood the heater and make starting it a pain.
 
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One of the ones I fitted on the boat (going from a
Eberspacher Airtonic to a Chinese 5kw) I used the same pump. As that one had a filter in it, not after it.
Also extended the wires to the lcd remote.

When first turned on press and hold the OK button & the down button. H and (off flashing) press up button and pump will start and go into prime mode. Let it run its full cycle. You may have to repeat.

Then press on to run.

The pump will only push fuel not suck it through.

For pipe I used a length of left over from air suspension install.
The pipe that come with it went in the spare come in handy one day bin.

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Nice idea. But in your set up is the fuel pump close to the diesel heater. Mine goes quite some distance from the fuel pump to the heater. Would that make a difference?
Where did you get the syringe from?

Heres my set up
diesel heater.jpg
 
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You could do with the pump being close to your fuel tank as the pumps are good at pushing but not so good at sucking.
I have an aluminium fuel tank mounted under our van, and as you can see the pump is mounted very close to the tank.
I just bought a 50ml surgical syringe off eBay.

1661950638035.png
 
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jollyrodger as you mention the fuel pump only pushes and doesnt suck, so how did you get diesel between the fuel pump and the diesel heater to begin with. Thats probably a good place for me to start, considering i have about 2.5m of air currently between the fuel pump and the diesel heater. I tried the priming function but the diesel in the tubes is just pulsing and not being fed through
 
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On that one, fuel was already in the system so easy enough. But it did have a hand primer "bulb" similar to outboard fuel tanks. Fitted by previous owner.
On other fittings I have primed by not fitting first off to the heater but let it pump into a jar at a lower level. Then fitting to heater.
Have one in the camper (and the flat) was straight forwards.
There is a farce book group if you have fb.

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Last edited:
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OK Ive bought some of the new smaller white nylon hose and today Im going to put one end in a bottle of diesel and suck it through to the diesel heater, then connect the end im sucking to the diesel heater, then run round and connect the other end to the diesel heater fuel pump and then take the other hose from the fuel pump and put it in the bottle of diesel.
Hopefully that should minimse the air bubbles and will have another try at priming it.
 
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GREAT NEWS. I FIXED IT!!!!

:D

So Ive ended up using the old original diesel heater pump with my new diesel heater and ive swapped the fuel line from the big green to the white nylon one.
The new fuel pump seemed to have trouble sucking up the diesel even when priming and i had no idea what to do about that. So another thing was probably my own fault, i had only been priming the system for a few seconds at a time because i'd read horror stories about flooding the heater and wanted to avoid that.
I primed it first from the fuel tank to the fuel pump. THEN I connected the hose from the fuel pump exit end and primed it until diesel squirted out the other end....THEN I connected that end to the diesel heater and bingo.
Thanks for all your help and i hope this posts helps others one day.

Heater is 5KW and my god it puts out some hot air. Its like I have an oven door in the van. I just wonder if it will get TOO hot even on the H1 setting.

Someone said putting it in high altitude mode uses less diesel and makes it run cooler
 
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Looks like you may be better off with the 2kW version with the size of your van rather than a 5kW, but next winter will answer that question.

The high altitude setting on Chinese diesel heaters is fake unless they have redesigned and are fitting new type motherboards now.
 
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Where do you get the 4mm hard plastic fuel pipe to replace the green one?
 
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jopparocks said:
Where do you get the 4mm hard plastic fuel pipe to replace the green one?
Click to expand...

I used 4mm airline (air suspension) you'll find it on ebay somewhere or down this way a firm called pressure lines.

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The point is that you don't get 4mm.
You get the narrower nylon tube. This means its easier for the fuel pump to push the diesel through.
Then you put the rubber sleeve over both ends and make it tight with some jubilee clips.

The kits are on ebay and amazon about 8 quid
 
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Yeah maybe you're right. I wouldn't have known until i fitted it.
Potentially I'll open a window to balance it out and get some fresh air also.
I've got a little mini electric heater to take the edge off things when it's only a little bit cold.
Some reviewers have said not to put the diesel heater:

A) on when driving

B) on the low H1 setting for long periods.

Anyone know if that's correct?
 
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Farcebook group full of answers re setting.

Code 1688

Or this guy Aussie John has a few vids

 
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Cheers. I didn't know about those groups. They look pretty substantial!
Will check it the video too
 
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Any *tiny* air ingress stops the pump working and pulsing, so may well be a knackered pump but also could be just a connection that wasn't 100% sealed. They will "pull" as much as branded pumps.

Before you go into admin and tweak settings, write down what all the settings are. Some controllers don't have altititude adjustment, so you may want to upgrade controller - but then you need to program the original settings. *lots* of the issues with these heaters is peple change controllers or settings without keeping the original settings (new controller will have random settings and overwrite the heater settings).

We also upgraded filter to a moped one - the plastic ones can break easily. We carry spare, filter, glow pin and tool, pump, controller, gauze, gasket and temp sensor (About £50). So far - no spares needed - runs a treat :) We also run it on kero rather than diesel as it runs cleaner and less internal sooting.

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TobyQuest said:
Yeah maybe you're right. I wouldn't have known until i fitted it.
Potentially I'll open a window to balance it out and get some fresh air also.
I've got a little mini electric heater to take the edge off things when it's only a little bit cold.
Some reviewers have said not to put the diesel heater:

A) on when driving

B) on the low H1 setting for long periods.

Anyone know if that's correct?
Click to expand...

A) No reason not to. Gas, yes, diesel, is fine.
B) Yes, as the heater can soot up. However, if you run on Kerosene (heating oil) rather than diesel it runs cleaner and less soot. But a good hot "burn out" once in a while is good for them.
 
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Nice. But where do you get kerosine from?
I fixed it actually. Basically it looks like i had to prime it step by step, first to the pump then from the pump to the heater.

The irony with it is that you need to print it to get the air out but when there's too much air in it you can't prime it.
 
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TobyQuest said:
Someone said putting it in high altitude mode uses less diesel and makes it run cooler
Click to expand...

lol. It will increase air-fuel ratio so I guess it could. But look around to how many people have sooted up/failed heaters and compare to those who have tweaked air/fuel ratios for one reason or another (or changing controller with random setting) - there is probably a good correlation
 
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I don't think i want to mess with the settings. Sounds like a headache waiting to happen. But i am kind of getting buyers remorse that i installed a 5 kw when a 2kw was probably more than sufficient.

I just saw a video where someone recommended to get a bigger one and so i did
 
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TobyQuest said:
Nice. But where do you get kerosine from?
I fixed it actually. Basically it looks like i had to prime it step by step, first to the pump then from the pump to the heater.

The irony with it is that you need to print it to get the air out but when there's too much air in it you can't prime it.
Click to expand...
You should be able to prime it still if all connections are 100% tight. I've set up on a bench and could duplicate the issue you had - and I was getting annoyed lol, redid connections and worked. Must've been one connection that was allowing tiny air ingress....
My first 20L was from an online oil site (same price as diesel at the time)
Then you can fill the container from a pump from garages that sell it. I found a supplier in Wellington near parents.
(I can of course fill with diesel if needed)

Tank is fitted with motorbike quick release (non drip) fuel connectors so I can remove tank and fill outside of the van.
 
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