[Pierre O]

Good luck! I hope it goes smoothly. I’m almost ready to buy one, but I’m waiting for a good video of the install.

For what it's worth all these heaters, independent of manufacturer, install the exact same way. Some tend to be Webasto clones whereas others are Espar clones (the generic Chinese units are mostly Espar-like but the Bison for instance is a close copy of a Webasto) but that does not impact mounting, it has more to do with internal layout and maintenance. Other than small dimensional differences (the 4 KW units being a bit larger than the 2 KW ones, and having larger heat ducting), the mounting plate, pump, fuel pickup, wiring, controller etc. are all connected and mounted in the same manner. Pick any video you like, picture the unit as being orange, and you'll be OK .

 

[Pierre O]

Personally I used the factory fuel tap. I figure if at any point we want to switch to a stanpipe all it cost us is 50 dollars for the fittings and all I have to do is put the cap back on.
As far as I know very few people put standpipes on promasters although if you look it seems quite common on ducatos which should be quite similar...

 

[Pierre O]

...plus I understand that Velit does not state that the auxiliary tap will not work; only that it may hinder high-altitude start-up. I'm a stong advocate of the stepwise approach to install and I would probably test with the tap prior to throwing the standpipe in the mix, at least to validate the rest of the install.

 

[Pierre O]

...pus for what it's worth the fuel pump is a critical (and fairly expensive) component and I'm not keen on drilling holes into it if I don't have to, on the odd chance that the manufacturer would not cover it under warranty if it fails (by itself or as a result of my intervention). For us high altitude travel is not in the short term plans anyway; but if you want to do it right now it seems quite straightforward (certainly less nerve-wracking than drilling holes for windows ). I would get a real tool to remove the lockring.

 

[Pierre O]

You mean to attach the hoses to the heater? Ours (not a velit) came with 1" worm clamps that seem like plumbing clamps. Any hardware store should have similar clamps.

 

[Pierre O]

No- to fix the hoses to the van’s frame.

Our bison kit had some steel straps about 1" wide and 4" long that you can wrap around the hoses and bolt to the frame. If your kit did not come with any, in a pinch all-round would work. The exhaust pipe is quite stiff so I used multiple straps to hold it where I wanted.

 

[Pierre O]

If they had known defects it seems they should have been more proactive and contacted customers and recalled components.

Great point. My impression is this is quite a small company; in my experience often these companies don't have the systems in place to allow for traceability to the individual component or lot level.

 

[Pierre O]

There are some pretty large companies that seem to have the same problem

Gary

For sure - traceability is one of the most complex aspects of electronics manufacturing, especially when the supply chain is global. It was not meant to be a criticism - this is something startups usually learn when they have to deal with their first recall or when a large customer imposes it.

 

[Pierre O]

Well @Showtime I heed your warning, as I do not have a need, so I have the luxury of waiting for the Empirical Data 😁.

I believe any of these RV heater furnaces can be problematic ,,, All of Them !!

I can't attest for the Velit but many/most problems with these units (independent of brand) are user caused, often through improper installation or by using outside of the altitude spec.

Inherently, due to their design, they are very sensitive to installation of the combustion air intake and exhaust, and also the fuel line. Many people disregard the instructions (line length, orientation, etc.) and many run into problems.

Ours (a General Components Bison) runs very well so far. We're just back from a 4-day trip where it ran for about 40 hours, and burned about 10 liters. It is really great to tap into the fuel tank when you have extensive usage. But you need to remember they are not "furnaces"; they are "heaters".

 

[Pierre O]

Can you clarify your statement; But you need to remember they are not "furnaces"; they are "heaters". As I do not know what you are getting at?

What I meant is they are not really designed (at least not the liquid fuel heaters) for fine temperature regulation. Combustion is optimal when they are run at full power, and the cycling on/off takes several minutes (again for the fuel heaters) and considerable power. Many have a thermostatic mode but even then the range of usable power is only about 2:1 (max to min) so the effectiveness is limited.
To me a furnace is like a Suburban RV unit, which regulates by switching on/off like a home gas furnace does. Maybe the propex units are also like that, I have no experience with them.

 

[Pierre O]

Hi RV,
Our Suburban propane furnace has been very reliable at all altitudes.
The thermostat cycles it off and on and controls the temperature within a couple degrees.
The installation is straightforward - in part because they really don't leave you any options.

I've never had to clean it or adjust it over something like 8 years. It has never failed to start and run on the first try.

It is built in the same way as my home propane furnace. It has the same sort of burner, igniter, blower and heat exchanger as my home furnace. And, it has the same safety features (flame detector etc.).

Honestly if there were a proven gasoline furnace, I might well switch to it and go to an induction cooktop and regain the space my propane tank takes up. Maybe the Velit is it, but since I have a solution that works well now, I'm going to wait and see.

Gary

Yes - the suburban/atwood (now Dometic) -type units have been built forever and ship with pretty much any RV so it's many millions of units overall. They've definitely proved to be reliable and safe and as you say, the installation is quite difficult to "mess up". They tend to be mostly installed at the factory by RV manufacturers anyway.

The webasto/eberspacher-type units have also been built forever but from what I understand the main markets are boats, machinery and heavy trucks. They tend to be mostly installed by service shops and have more ways where you can go wrong, both during installation and usage.

To us gasoline was the choice and we knew the trade-offs going in. We went with GC primarly because they support DIY customers (both for sales and after-sales) better than Webasto and Eberspacher. So far so good but fingers crossed 🤞.

 

[Pierre O]

Had a flashback, what were the VW Bug gasoline heaters, anyone remember? They were mounted in the front under the hood.

Mostly Eberspacher heaters, primitive versions of today's models but with the same operating principle.

 

[Pierre O]

That’s part of what is different about the VeLit. Webasto had to do that. Velit doesn’t. We can run it low overnight, turn it off in the morning, no worry about carbon buildup.

They describe the routine after turning it off “cooling down,” and that’s what it does. Seems like it’s just blowing the fan for a bit.

If it's like the other gasoline heaters (don't know about diesel), when you turn it off it starts by slowing down the pump and fan and turning on the glow plug. After a while it stops the pump, and combustion will stutter for a few seconds. Once it stops the glow plug will burn any residual gasoline, this is when you may get some white smoke. Then the glow plug and finally the fan will stop.

 

[Pierre O]

Curiously, over its range, the Espar uses about half the power as the VeLit, yet more than twice the fuel, for half the BTU.

I don't know about power but for gasoline that would be surprising.
Normally a 2 kw heater draws about 0.25 l/h and a 4 kw heater about 0.5 l/h. Seems the velit is the same (0.14 g/h or approx 0.5 l)?

 

[Pierre O]

You caught it. G/hr vs l/hr. My bad.

Ok - that makes sense. Really the efficiency of these things should be quite close between vendors as they all basically squirt gasoline on a flame...

 

[Pierre O]

One of our earliest and most resolute decisions was that we would NOT add diesel or propane, plus I absolutely did not want vents in the van’s sheet metal. Period. Also, if we had decided to relent on the propane two years after the initial build, there would have been major compromises somewhere to fit in a tank and heater. We understand the advantages of propane, but it is not our cup of tea. Glad it works for you.

Our previous experience was with gas Webasto, which worked perfectly as long as we ran it only on high and below 7,500 feet (with altitude adjustment). Four winters without maintenance until we got desperate one night at 8,500 feet.

💯. We also did not want propane. Of the 2 options for carrying it, I was not going to have a 20 lb tank inside. I understand they can be made safe, but I am afraid of propane. That's just me. I even treat 1 lb green tanks with considerable respect. The other option was an underbody tank. I would have been relatively comfortable with this from a safety standpoint. These are also typically 20 pound tanks if I remember well.
We camp in cold conditions in the winter. Last weekend over a 72 hour period we burned 2.6 gallons of gasoline for heat, or 300,000 BTU. Assuming 70% efficiency we got about 210,000 BTU as heat. Now assuming a propane furnance is 85% efficient we would have needed 248,000 BTU, or 11.5 pounds, of propane.
So basically this means that for us, for only a long weekend trip, already I would have had to get the tank (BBQ tank or underbody tank) filled prior to the next trip. With a gasoline heater I just pumped an extra 10 liters in when I filled up on the way back.
So to us, a gasoline heater was the compromise we were willing to live with. Again I'm not suggesting it is for everybody. For most people propane is probably the best compromise; but not for us.

 

[Pierre O]

How do you measure so precisely? So far, all we can tell is our fuel mileage is a bit worse than it would have been on this tank.

I compared how much fuel I pumped in vs how much the engine burned since last fillup (calculated from distance driven and trip computer field consumption). It arrived at 10 liters burned in the heater, which means 40 hours burn time which is in line with our recollection of the weekend. It may be 10-15% off (plus or minus) but not much more.

 

[Pierre O]

Very well then. There's a reason there arent hundreds of posts about how to keep propane furnaces operational. Propex doesnt have vents in the sheet metal, it mounts thru the floor. A propane locker is very simple, its just an airtight box that vents thru the floor, nothing to be afraid of and running tiny plastic hoses full of gasoline into the inside of the van is not safer. Liquid fuel heaters do occasionally go up in flames. I hate to hear that someone is using a gasoline heater because they perceive it to be "safe". Its a shame that they take up space in the van. I take out my propane locker in summer and use 1# green bottles for cooking in summer.

As far as I know none of the liquid fuel heaters are maintenance free, they will all soot up and require rebuild eventually.

Why would one run gasoline lines inside the van? The complete fuel line and the fuel pump are all outside under the floor in a normal installation.
And BTW RV furnaces are reliable but they do fail as any RV forum will show. And RVs do blow up from propane explosions occasionally as well. No non-trivial technology is perfect; it's all about what set of trade-offs works best for you.

 

[Pierre O]

Safety is the most important item in my mind. I do not know the “safety records” & what is “safer”. I also believe “no Forum Member here” is the keeper of such data ,,, examples with low resolution “sure”, but properly analyzed statistics 🤷‍♂️.

If we consider the DIY Van Builder On This Forum & the Typical RV Owner into the safety equation, I assume the DIY generally knows their heater system better than the Typical RV Owner. I also assume as the DIYer can fix & repair & inspect their heating system, they would generally be “safer” than the RV average.

Sometimes analysis is counterintuitive ( Like Aviation Insurance & General Aviation Twin Engine Airplanes ).

If a DIYer “fears” a fuel source, I suppose they should stay away from that fuel source.

My option is the propane furnaces In am interested in are more reliable & have fewer problems typically than the gasoline or diesel units. I reason this, by looking at the RV Industry & pondering the common fuel & equipment.

Yes, my point was not about which is safer. All I said was there is risk involved with both. What the relative risk is I do not know.

 

[Pierre O]

I rolled a paper towel up tight and swabbed the interior of the exhaust pipe as far as I could reach. It came out clean. This is after probably 100 hours of running on the lowest setting, admittedly at low altitude because that’s where we are in winter.

This is a good, quick check. One good test also regardless of brand and model is to use a CO tester such as this: Handheld Carbon Monoxide Meter Portable CO Gas leak Detector Gas Analyzer High Precision detector de gas Monitor tester 1000ppm - AliExpress periodically to see that combustion is clean. I do it once every 3 months or so, and also stick it next to the heater outlet inside to make sure that there is no leaking through the gaskets.