[RV8R]

After the initial start up failure, and it started again just fine, and ran all day. Outside temp was 35 and the can was at 70 when we hopped back in. I’ll keep an eye on the voltage coming from the battery next time. I had driven 2 hours and the 100amp hr lithium should have been topped off. Thanks for the advice.

Typically less of an issue with LFP, but the liquid fuel igniters (glow plugs), can take a bit of 12v power. You can verify the voltage at the heater with a multimeter when it is attempting to ignite.

None of these heaters are “flawless” but hope you do not suffer any further issues. Good Luck with it & please report back your experiences ,,, Good or Bad 😁👍.

 

[teethandnails]

Typically less of an issue with LFP, but the liquid fuel igniters (glow plugs), can take a bit of 12v power. You can verify the voltage at the heater with a multimeter when it is attempting to ignite.

None of these heaters are “flawless” but hope you do not suffer any further issues. Good Luck with it & please report back your experiences ,,, Good or Bad 😁👍.

I have to go out of town for a week tomorrow, but I can check that when I get back. I have it wired into my fuse block with a 20amp fuse on the block plus another 20amp in line.

 

[RV8R]

I have to go out of town for a week tomorrow, but I can check that when I get back. I have it wired into my fuse block with a 20amp fuse on the block plus another 20amp in line.

Hey @teethandnails

I am not at all saying that you have “voltage drop”, just that I experienced that with my $150 cheap Amazon Diesel heater ,,, so made mention. That diesel heater came with a wiring harness that in my mind was too long & too thin of wire ,,, ok for amps but not for voltage drop.

Regardless; If you want to know more about that & circuits;

Top Left Hand Corner of that Chart 3% Critical;

Blue Sea has “Critical Loads” @ 3% voltage drop on their chart. You can see a significant reduction of the circuit length allowed @ 3% on critical vs 10% non critical.

Part 1: Choosing the Correct Wire Size for a DC Circuit - Blue Sea Systems

Engineering high quality marine electrical components for safety, reliability and performance

www.bluesea.com

 

[RV8R]

I have to go out of town for a week tomorrow, but I can check that when I get back. I have it wired into my fuse block with a 20amp fuse on the block plus another 20amp in line.

Hey @teethandnails

I am not at all saying that you have “voltage drop”, just that I experienced that with my $150 cheap Amazon Diesel heater ,,, so made mention. That diesel heater came with a wiring harness that in my mind was too long & too thin of wire ,,, ok for amps but not for voltage drop.

Regardless; If you want to know more about that & circuits;

View attachment 112380


Blue Sea has “Critical Loads” @ 3% voltage drop on their chart. You can see a significant reduction of the circuit @ 3% on critical vs 10% non critical.

Part 1: Choosing the Correct Wire Size for a DC Circuit - Blue Sea Systems

Engineering high quality marine electrical components for safety, reliability and performance

www.bluesea.com

 

[larry barello]

Ok, after resetting the heater, I fired it up again and it’s pumping hot air into the van! Not sure why it took two goes, maybe due to the higher altitude it needed a minute to adjust. For reference my house is at 5280ft, and I’ve started the heater 5 times with issue in the past week.

Sometimes, after a long period of non-operation (> 6 months) my Webasto takes two tries before firing up. I am guessing a bubble develops in the fuel pickup or delivery lines that needs to be purged.

The elevation change might have caused a bubble to form and the two restarts to flush out. It's also possible that with the new installation heater is still purging stray bubbles from the line.

 

[RV8R]

Sometimes, after a long period of non-operation (> 6 months) my Webasto takes two tries before firing up. I am guessing a bubble develops in the fuel pickup or delivery lines that needs to be purged.

The elevation change might have caused a bubble to form and the two restarts to flush out. It's also possible that with the new installation heater is still purging stray bubbles from the line.

Exactly;

 

[teethandnails]

Exactly;
View attachment 112393

I have observed pockets of air in fuel line and assumed this was normal

 

[RV8R]

I have observed pockets of air in fuel line and assumed this was normal

It is a bit of an achilles heel on the fuel delivery.

Typically going up higher altitudes in a closed system any trapped air “expands”.

Your system’s fuel lines should be tight so the pump does not suck in air from the connections ,,, also setup to self purge ,,, air rises in the lines. The issue with air in the lines is;

1) When it (if) reaches the burner, there is a lack of fuel

2) In the line “dose pump” cycles rely on the fuel hydraulics (no compression), & if enough tiny bubbles exist the air can compress on the pressure side or expand on the suction side, reducing the dose pumps ability to do it’s job.

 

[Pierre O]

I have observed pockets of air in fuel line and assumed this was normal

"pockets" of air (meaning air gaps of few millimeter length or more) are definitely not normal, they usually mean air gets sucked in somewhere between the tank and the pump.

 

[teethandnails]

"pockets" of air (meaning air gaps of few millimeter length or more) are definitely not normal, they usually mean air gets sucked in somewhere between the tank and the pump.

So, I am at altitude again (10,500ft) and the heater through the 07 error and did not start up properly. I looked under the van, and saw gaps about an inch to 3 inches in the fuel line. I primed the system for about 30 seconds, and it started fine. It sounds like I need to tighten the fuel lines to the pump then? Should I use black fuel lines vs the clear with the black junctions for a better seal?

 

[Pierre O]

So, I am at altitude again (10,500ft) and the heater through the 07 error and did not start up properly. I looked under the van, and saw gaps about an inch to 3 inches in the fuel line. I primed the system for about 30 seconds, and it started fine. It sounds like I need to tighten the fuel lines to the pump then? Should I use black fuel lines vs the clear with the black junctions for a better seal?

Yes, probably your pump is sucking air; likely due to a small air leak between the tank and the pump. It's probably a very small leak, otherwise it would not prime at all...

I don,t know what pup velit uses but our bison heater has a fuel pump that dispenses 68 microlitres per pulse; that represents about 1 1/2 inches in the hose. So 3 inches means maybe 2 clicks where the heater doesn't get gasoline; it's quite significant especially if you have several such air blocks in your line.

Supposedly the rigid line is necessary between the pump and the heater to get proper fuel delivery but I would guess normal fuel hose is probably OK between the tank and the pump, although I never tried it.

 

[teethandnails]

Yes, probably your pump is sucking air; likely due to a small air leak between the tank and the pump. It's probably a very small leak, otherwise it would not prime at all...

I don,t know what pup velit uses but our bison heater has a fuel pump that dispenses 68 microlitres per pulse; that represents about 1 1/2 inches in the hose. So 3 inches means maybe 2 clicks where the heater doesn't get gasoline; it's quite significant especially if you have several such air blocks in your line.

Supposedly the rigid line is necessary between the pump and the heater to get proper fuel delivery but I would guess normal fuel hose is probably OK between the tank and the pump, although I never tried it.

When you say rigid line, you are referring to the stand pipe? I will tighten the clamps on the line going to the pump to start and go from there.

 

[Pierre O]

When you say rigid line, you are referring to the stand pipe? I will tighten the clamps on the line going to the pump to start and go from there.

No I meant the rigid white/translucent line normally shipped with your heater kit.

 

[teethandnails]

No I meant the rigid white/translucent line normally shipped with your heater kit.

Got ya

 

[Pierre O]

No I meant the rigid white/translucent line normally shipped with your heater kit.

One thing you can try if the velit has a purge mode is to take the line connected to the heater, remove it and dunk it in a glass of gasoline and run a purge cycle to see if you have bubbles.

 

[83Grumman]

I will tighten the clamps on the line going to the pump to start and go from there.

Put a drop of oil on the hose under the clamp. I've seen fuel lines and hoses pinch from clamps when the clamp "gathers" the rubber on one side. I always use a bit of oil under clamps on hoses.

 

[LanVan]

So, I am at altitude again (10,500ft) and the heater through the 07 error and did not start up properly. I looked under the van, and saw gaps about an inch to 3 inches in the fuel line. I primed the system for about 30 seconds, and it started fine. It sounds like I need to tighten the fuel lines to the pump then? Should I use black fuel lines vs the clear with the black junctions for a better seal?

Here's a long shot: I had a situation once where I went low elevation to high but the gas tank got more empty than I had planned en route, obviously exposing the draw tube in the tank. The combination required me to prime the line but it worked OK after that. @Pierre O 's suggestion to check for ongoing bubbles in the line is a good one as it will expose any leaks upstream from the pump. Downstream there should be some air but not 3" worth.

I've had a long and tense relationship with my Velit heater, of which I was an early adopter. I've replaced ECU's, controllers, burn chamber, and pump, re-run fuel line and in general messed about with it much more than I had hoped. Customer service has been long on sending me parts but relatively short on real answers. Is it a bad unit? Not really. But I do not believe for a moment that they have magically solved the elevation issues that go with this primitive style of heater and my part-time job as beta tester proves me right, as does the fact that the new controller includes a "Cleaning" mode. Nothing in the marketing or included manual suggested this is required, quite the opposite.

Most of my problems with the unit stem from the false idea that Velit has figured out how to run reliably at altitude. I'm sure some people have had better luck than I, but my time with the Velit have taught me these things:

1. Always run the thing on high for 10 minutes minimum after any time at lower output, regardless of elevation. This will help keep the carbon buildup at bay.

2. If you keep getting fuel error codes, check the flow rate. You can do this while checking for bubbles. Time the pump in prime mode and measure the output. According to Velit, the pump should put out 11-14ml of fuel per 30 seconds of running in prime mode. When I did this measurement, I did so for a minute and measured 28ml, despite getting fuel warnings. It turns out that the atomizer screen in the burn chamber had started to get carbon build-up and the heater is not smart enough to know that it was getting fuel, just not igniting. So, that brings me to. . .

3. Don't assume the error code you see is accurately describing the direct issue. In my case, I was chasing false fuel flow problems when the real issue was related to basic shortcomings of this design: carbon build up when used at high elevations and/or long usage at less than highest output.

There's a lot to like with this machine, and it has added immense comfort to our shoulder and winter season camping, but it's not magic and has let me down multiple times in a variety of situations. I am hopeful that future issues will be avoided by running on high for 10 minutes (or more!) every single time I use it. I've not been back to high elevations since replacing the burn chamber and rigorously following the 10 minute rule but I am optimistic I've finally gotten to a stable place.

Good luck in your journey, I hope it does not take as much of your time as it did mine to achieve reliability.

 

[Pierre O]

Here's a long shot: I had a situation once where I went low elevation to high but the gas tank got more empty than I had planned en route, obviously exposing the draw tube in the tank. The combination required me to prime the line but it worked OK after that. @Pierre O 's suggestion to check for ongoing bubbles in the line is a good one as it will expose any leaks upstream from the pump. Downstream there should be some air but not 3" worth.

I've had a long and tense relationship with my Velit heater, of which I was an early adopter. I've replaced ECU's, controllers, burn chamber, and pump, re-run fuel line and in general messed about with it much more than I had hoped. Customer service has been long on sending me parts but relatively short on real answers. Is it a bad unit? Not really. But I do not believe for a moment that they have magically solved the elevation issues that go with this primitive style of heater and my part-time job as beta tester proves me right, as does the fact that the new controller includes a "Cleaning" mode. Nothing in the marketing or included manual suggested this is required, quite the opposite.

Most of my problems with the unit stem from the false idea that Velit has figured out how to run reliably at altitude. I'm sure some people have had better luck than I, but my time with the Velit have taught me these things:

1. Always run the thing on high for 10 minutes minimum after any time at lower output, regardless of elevation. This will help keep the carbon buildup at bay.

2. If you keep getting fuel error codes, check the flow rate. You can do this while checking for bubbles. Time the pump in prime mode and measure the output. According to Velit, the pump should put out 11-14ml of fuel per 30 seconds of running in prime mode. When I did this measurement, I did so for a minute and measured 28ml, despite getting fuel warnings. It turns out that the atomizer screen in the burn chamber had started to get carbon build-up and the heater is not smart enough to know that it was getting fuel, just not igniting. So, that brings me to. . .

3. Don't assume the error code you see is accurately describing the direct issue. In my case, I was chasing false fuel flow problems when the real issue was related to basic shortcomings of this design: carbon build up when used at high elevations and/or long usage at less than highest output.

There's a lot to like with this machine, and it has added immense comfort to our shoulder and winter season camping, but it's not magic and has let me down multiple times in a variety of situations. I am hopeful that future issues will be avoided by running on high for 10 minutes (or more!) every single time I use it. I've not been back to high elevations since replacing the burn chamber and rigorously following the 10 minute rule but I am optimistic I've finally gotten to a stable place.

Good luck in your journey, I hope it does not take as much of your time as it did mine to achieve reliability.

I spent considerable time designing and manufacturing sensing systems; the reality is usually it is tolerances that hurt performance, unless (or even if) you spend considerable time characterizing each component and calibrating each sample.

For instance, "11-14 ml" is a quite large tolerance; of course it is a bell curve and maybe most samples are close to the nominal value but the issue with volume manufacturing is tolerances add up; unless your Cp / Cpk are good you will get either a very low yield or (more likely) many customer complaints.

There is no magic so what you're suggesting is sound ways to maximize the performance of any liquid fuel heater.

 

[kenandlinmarie]

So, I am at altitude again (10,500ft) and the heater through the 07 error and did not start up properly. I looked under the van, and saw gaps about an inch to 3 inches in the fuel line. I primed the system for about 30 seconds, and it started fine. It sounds like I need to tighten the fuel lines to the pump then? Should I use black fuel lines vs the clear with the black junctions for a better seal?

The weak point in my installation was the nylon to rubber junction just before the fuel pump. The hose clamps supplied by Velit couldn't be tightened enough so I had to buy some worm gear clamps from Lowes instead. My issue was a dripping of fuel and air in the line while trying to start the heater.

The Lowes small worm gear clamps solved that issue of having air in the fuel line and dripping fuel during startup. After clamping I tapped and flicked the bubbles out of the line going up to the heater. It's working great now.

I also have 1/4" rubber fuel line protecting the nylon line like a conduit against road debris. But no clamps are needed around that as you can see.

 

[teethandnails]

The weak point in my installation was the nylon to rubber junction just before the fuel pump. The hose clamps supplied by Velit couldn't be tightened enough so I had to buy some worm gear clamps from Lowes instead. My issue was a dripping of fuel and air in the line while trying to start the heater.

The Lowes small worm gear clamps solved that issue of having air in the fuel line and dripping fuel during startup. After clamping I tapped and flicked the bubbles out of the line going up to the heater. It's working great now.

I also have 1/4" rubber fuel line protecting the nylon line like a conduit against road debris. But no clamps are needed around that as you can see.

View attachment 112761
View attachment 112760
View attachment 112759

How tight are you wrenching down those clamps?