TheSamba.com :: View topic - The official Chinese Diesel Heater thread (Webasto Knockoff)

Sun Jan 13, 2019 6:18 pm

Dave, Read the entire topic and most of your questions are answered in there. :D

Sun Jan 13, 2019 8:23 pm

It would be unpleasantly loud to run inside your van while trying to sleep. The thing really blows a lot of air and sounds like a jet engine.

You could pipe the exhaust out of a window cracked an inch, but exhausting it inside the van is a no-go. When it fires up and shuts off it blows toxic hydrocarbons. While running the exhaust is pretty clean.

The unit I referred in my previous post comes set to 6,200 ft of elevation and is supposedly adjustable for much thinner air. I am in Santa Fe at 7,200ft and it runs pretty clean. There’s a menu setting where you can enter an access code and change default settings like elevation

I should also warn you that the unit pulls about 9 amps for quite some time while starting up. Once hot the glow plug shuts off and it pulls about 2-3 amps from the blower and fuel pump. Running it cycling on-off on a cold winter night is going to take a solid auxiliary battery.

Sun Jan 13, 2019 10:02 pm

Gnarlodious wrote:
I should also warn you that the unit pulls about 9 amps for quite some time while starting up. Once hot the glow plug shuts off and it pulls about 2-3 amps from the blower and fuel pump. Running it cycling on-off on a cold winter night is going to take a solid auxiliary battery.

Propex does not have the initial start up draw, but it does pull close to 2 amps while running, it does not run all the time. The diesel heaters will "throttle down" to maintain set temp, so they run kind of all the time, but will drop to 1 amp once the van has warmed up, well, this is for the non knock off diesel heaters, but I assume the knock off diesel heaters are the same. With a propex the temp swing form when the heater shuts off to when it turns back on is 14* F, kind of a big temp swing, assuming its "cold enough" outside the diesel heaters should be able to maintain a tighter set temp with their ability to run at "part throttle".

I think power consumption between the 2 would be close, but my hunch is that the diesel will pull a bit more juice over the course of a night with its high startup draw and constant running vs the intermittent higher running draw of the propex with no heavy startup draw.

My propex has been decent, but it has not operated as reliably with my solar system as I'd like, in the winter the peak charge voltage for an AGM battery is 15.2 volts at 0* F, which is too high for the propex, so on a sunny cold day I have to run other electrical draws to get the voltage down so the heater will start up, then when the heater shuts off the voltage climbs back up, then the van cools down the heater won't come back on because the voltage is too high.

I think I did just recently solve this problem though, a DROK adjustable 12v regulator from Amazon seems to have it working well so far during driveway testing in zero degrees and blazing sunshine. EDIT- The propex has run reliably in cold weather with DROK voltage regulator.

https://smile.amazon.com/gp/product/B00CNXLDCQ/ref...&psc=1

The propex does make heat quicker than the diesel heaters, the flame chamber is much thinner lighter metal and the propane burner will ignite and run full blast tight away, where the diesel heaters need to throttle up slowly over the course of a few minutes to get to their full output, and the flame chamber has notably more mass so that also takes longer to heat up.

Pros and cons to each of them.

Tue Jan 22, 2019 10:00 pm

Just for fun a couple of days ago I was playing around with my heater in the garage.

It was approximately 15F outside and my "8kw" heater managed to hold the inside temps at about 42F.
Not real warm by any means but an F lot better than 15.

I turned my double burner propane heater on and cranked it on high.
the temps then jumped up to 50F and kinda hovered there for the time I was out there.

My garage is approximately 25x25 feet, made of block walls and virtually uninsulated.

I did measure the outlet temp of the diesel heater and it stopped around 168F.

I tinkered around with the fuel pump frequency and that changed things considerably.

With the pump set at 5Hz, which seems to be the max, the temps at the outlet reached their max.
I turned it down to 4Hz and after a couple of minutes the outlet temp dropped to around 148 before I realized that it was clearly not working and turned it back up.

There may be ways to change some other things but I have not explored that yet.

Perhaps someday I will nerd out on it and break something but I have got bigger fish to fry at the moment.

I am going to order up some more duct work so I can bring the heat to me and and carry on with my van build for now.

Wed Jan 23, 2019 10:11 am

If that heater is putting out 17,000 BTUS you should be able to heat that garage to whatever temp you want. My Colorado condo had a 17,000 btu furnace.

But that probably assumes you keep the space warm all the time.

Wed Jan 23, 2019 11:08 am

Well technically it should be putting out 27000 BTU.
The point is I suspect that it is not putting out anything close to that.
It still heats and it would do awesome in a smaller space or a properly insulated space but, as expected, the output numbers are probably fluffed a little bit by the seller.

Wed Jan 23, 2019 12:15 pm

vwhammer wrote: With the pump set at 5Hz, which seems to be the max, the temps at the outlet reached their max.
Did you happen to take a reading to know what the "max" temps were at this point?

I recently bench-tested a couple of 5KW units running on kerosene, and my non-contact IR thermometer was reading around 300-310*F directly off the core (not the fins) of the heatsink inside the unit at full running temperature. Even dialing it back to the 2.0-3.0Hz range, I never saw the heatsink drop much under 200*F, though I admit I was more interested in measuring max temps than anything else.

Wed Jan 23, 2019 1:24 pm

I would love a lower vent temperature. I noticed that on some of the YT videos that people had reasonable output temps. My Webasto is a hot muther. You can't put your hand in front of it and the ducting has to handle high temperatures. IIRC it was up around 270 degrees which I believe is within spec but it is too freakin hot. I would love it if mine was 168 degrees. Seems safer for sure.

I also saw some videos that mentioned you can get into the heater settings that are password protected and change things. Not sure if that gives more options than the controller that have some of those options on the display, they might not all be the same ECU-wise.

Wed Jan 23, 2019 1:42 pm

tristessa wrote: Did you happen to take a reading to know what the "max" temps were at this point?

Sorry I may have worded my statement wrong.
I mentioned that I measured 168F.
That 168F was the max temp I saw at the end of the piece of duct work that you get with the heater. (don't know what length that is)
This was measured with a thermocouple placed right in the center of the pipe about 1 inch in measuring actual air temp.

Wed Jan 23, 2019 2:11 pm

I was kind of hoping to run the unit a little lean by slowing the pump down which I also hoped would bump the output temp a little bit.
This did not happen.

Don't know if changing the fan speed would do anything either.
I will say that when I changed what I think is the pump frequency it did sound like the fan slowed down some.

It's hard to say if this is because the frequency thing that I am adjusting is actually changing the fan speed and not the pump frequency or if the fan slow down is a function of the control scheme changing things based on the temp measurement it receives from it's onboard thermocouple.

If the frequency thing is actually changing the fan speed this may explain why the temps dropped.
Less air would mean it was running a bit on the rich side which might drop outlet temps.
I could not see the exhaust outlet while I was tinkering so I can't say if there was any change in the exhaust output.

Anyway I may have to set this up and do some proper tests.

For starters I am curious if it is simply a setting change between the gas and diesel versions or if there is actual hardware differences.

Secondly I am curious if settings could be changed for high altitude.

my 2kw unit has a high altitude function so I will have to see if I can tell what changes that one is making to run at high altitudes.

There is no good reason for me wanting to know any of this info other than maybe I can maximize the output and fuel usage with a few simple settings or possibly make it a multi-fuel deal.

It could be set up pretty conservative at the factory to make it kind if idiot proof.

Wed Jan 23, 2019 8:42 pm

The Hz adjustment is the pump frequency. The heater ECU adjusts the fan speed up/down to go with the pump frequency .. within the upper/lower limits set in the passcode-protected settings where one can adjust the min/man fan speed and min/max pump frequency.

Adjusting the heater output with the Hz is possibly a better way to set the output for long runs than a temperature. Set it for 2.2Hz and it'll run all night at that level. Set it for 18C and once it hits that it idles down on low until temperature drops, then ramps back up until it hits 18C again...

Good to know what temps you were reading and what you were reading it with. I used the IR thermometer because it's what I have in the garage, no thermocouples kicking around right now.

Mon Jan 28, 2019 2:15 am

Got my real 2kw heater yesterday.
Here is a comparison video between the 2kw and the 5kw

Wed Jan 30, 2019 5:39 pm

Installed my 2kw Sunday.
Still need to tidy things up and finish boxing in the heater but otherwise I’m happy with it.

Wed Jan 30, 2019 6:11 pm

That's about where we mounted the heater in my buddy's Syncro, only I got crafty with some pieces from the local HVAC supplier so the heat comes through the opening leftover from the OEM rear heater. Wish I had a picture...

Wed Jan 30, 2019 6:41 pm

Nice!

Wed Jan 30, 2019 7:21 pm

tristessa wrote: That's about where we mounted the heater in my buddy's Syncro, only I got crafty with some pieces from the local HVAC supplier so the heat comes through the opening leftover from the OEM rear heater. Wish I had a picture...

That’s one of the changes I’m gonna make. I just wanted to get it in and running. I need to replace that kick panel anyway, and until this install the leaking rear heater core was still in the way.

Wed Jan 30, 2019 7:35 pm

I have had a 5KW installed for a couple weeks now. I removed my Propex HS2800 and twin propane saddle tanks. We winter camp a lot and can burn through propane quickly. It was getting difficult to always find a place to fill them. Most of the people do not know how or act like they don't when I pull up. It was installed in the same footprint as the HS2800. So I realized about a 100lb weight savings on the van too.

The 5KW is too much when the temps are above 40°f outside. I usually open up the top vent and zip open the sides to let the heat escape. But I recently tested it a -04°f with the poptop up and the diesel heater was perfect. You could hear it cycling up and down as it maintained the set temperature of 22°C or about 72°f.

It does not use much fuel or wattage.

So far, I am sold. Time will tell.

Wed Jan 30, 2019 7:46 pm

Why exactly did you go with a diesel unit and not gas? Setting money aside - and if you had it to do again - what changes would you have made?

I love your setup for sure! Great work! I'm actually planning on deleting my propane tank and switch to 1lb canisters.

Personally, it's more attractive - and worth the money - to invest in a gasoline heater and tap into the fuel tank. However I'm more of a weekend warrior. I would rather refill the gas tank via some jerry cans.

Wed Jan 30, 2019 7:52 pm

shagginwagon83 wrote: Why exactly did you go with a diesel unit and not gas? Setting money aside - and if you had it to do again - what changes would you have made?

I love your setup for sure! Great work! I'm actually planning on deleting my propane tank and switch to 1lb canisters.

Personally, it's more attractive - and worth the money - for me to invest in a gasoline heater and tap into the fuel tank. However I'm more of a weekend warrior. If anything, I would rather refill the gas tank via some jerry cans.

I chose the diesel heater because of the volatility of gasoline. I also have been using Kerosene and #1 Red Diesel at a 4 to 1 ratio. Just enough red to see the fuel level in the tank. Since the 5KW is usually running it's lowest setting, kerosene does not soot up like diesel. My wife likes that the heater is always on and not cycling on and off. You can adjust the air/fuel mixture and get these to burn really clean and use very little fuel and power. For those who never camp in really cold conditions, I too would recommend a 2KW for our vans. But it sure is nice to crank it up and stay toasty! I also plumbed the stove to run on the 1lb cans. It works great! Cheers....

Wed Jan 30, 2019 8:00 pm

I went with diesel because of the cost, nothing more. Excellent bang for the buck.

Syncro Jael, have you tried adjusting yours using the pump frequency instead of the temperature setting? I'm looking forward to experimenting with mine this weekend, going camping on the Oregon coast with the WetWesties. Worst case if I get too hot is that I crack open the roof vent a tad, but I tend to be cold-blooded so I'm not sure "too hot" is possible. You can take the boy out of California, but you can't take California out of the boy...