8k chinese diesel heater in DP class A for dash heat

[Captain8]

There are sensors and alarms. So far I've had errors for no fuel (didn't prime enough), low voltage (tried running both on same thin gauge wire) and just today had an overheat error (both heaters on for about 2 hours) the screen shows if low voltage, if using fuel pump, if intake/exhaust is flowing and a little gauge for how warm the air is

[Fridge Defend]

Originally Posted by geordi

1) gentleman from Australia who has created an upgraded control for them that he calls the Afterburner.

2) I don't think it needs an optical sensor b/c it monitors the housing temperatures. If there's no fire, then there's no heat. It is pretty good at monitoring that,

3) b/c I have had difficulties purging the air from the fuel line (it is a tiny PWM pulse pump) and had to restart the heater multiple times to get it to light off at the beginning of the seasonal use.

4) Ignition is via a glow plug that should light off the fuel spritzed at it, but if the fuel flow is not sufficient, then it just fails out with a timed program. Then it goes into shutdown mode where the glow is disabled and it blows high volume air through to purge / dry out the combustion chamber before shutting down entirely. The shutdown program runs for around 45 seconds-1 minute or so.

5) On startup, it will spool up the fan first, then you can monitor the power usage and see when the glow plug is energized, it starts the fuel pump shortly after. If there is ignition, then the housing will start to warm and the system will drop back the power (glow plug off) and it becomes self-sustaining as long as the fuel cycle is maintained.

6) Heat generation is controlled by the fuel pulse speed and the fan speed - Although the fan is not terribly strong, so any restrictions in the outlet will reduce the airflow and the housing temperatures will be higher, the program will reduce the fuel flow to maintain around a 350 degree housing temperature... But with that reduced airflow, you are getting less heat in the cabin! It will adapt the fan speed and fuel pulsing once a temperature setpoint is reached, so it isn't just an "on/off" type of operation. It will slow down considerably at both fan and fuel pulsing (one pulse about every 3/4 second, and one pulse equals about 1/4 teaspoon of fuel) and stay like that until either you change the operation, or the setpoint becomes higher than the incoming air temperature from the cabin. Then it will ramp up again automatically.

7) As far as monitoring the combustion, it knows what it is injecting for fuel, so if the temperature starts dropping, then it knows that there was an issue (fuel out / flame out) and will go into the shutdown program with that error code displayed. The Afterburner control system just gives me a webpage display of all the information that the heater has, plus the option of app control, as well as a small OLED screen on a little control box. Everything that makes the heater run is still within the heater itself, his system is only interfacing through the existing remote control harness. I like it b/c I get more control and programmability (timers, etc) and even the ability to adjust the fuel mix, but the heaters will NOT allow outside control of the fan speed - I think b/c that is linked to the combustion system.

I built my setup with as few restrictions / bends in the pipes as possible, the diesel exhaust pipe exits horizontally right at the surface of the original furnace door - just like the original LP furnace did. There is no air intake for inside air anywhere near there, so as long as my furnace box is sealed up inside the wall (it is) then the "outside" side of that box behind the furnace door is only ventilated to the outside world. The only time that there is any smoke from the system is when it is starting up and the fire is "cold" or if it flames out and is running excessively rich once it does light off. During normal operation, the exhaust is not smelly, although there are zero combustion treatments happening... A good hot fire consumes everything though.

It only uses about .1 liters an hour while running, roughly 16-20 ounces for a visual reference. During my holiday trips, it would be operating 24/7 like this, and did a pretty decent job at keeping a 40' coach comfortable.

First, thanks for taking the time to explain the control system in detail

1) Yep, someone has recognized shortcomings, and these shortcomings could result in safety issues?

2) A fired system needs flame sensing to avoid a situation where the combustion chamber is not getting raw fuel in it that could cause a fire.
Although diesel is very safe due to its ignition point, just ask the folks with Sherman versus Tiger tanks in WWII, flame sensing is an important control on any burner.

3) PWM is the method of control for the burner rate via the pump.

Q1) Do you know the pump pressure?

4) Sounds like safety is via timer and combustion chamber temperature, that is all.

Q2) Do you know the amp draw for startup and running?

5) Glow plugs can fail, and they have to be more than red hot to ignite diesel. Again, this is of concern, a no flame situation is bad. But we may assume that safety has been built in so that the amount of fuel is limited in the combustion chamber. Also, the orientation of the heater I assume is critical to avoid pooling of unburned fuel.

6) If you read some of our posts on 'wind stagnation' for refrigerators, this can be an issue. Diesel requires excellent atomization of the fuel combined with turbulent air flow. In my years doing diesel repair, there were some Navy PT diesels that had some ingenious methods to increase combustion efficiency.


7) You can put a thermocouple/pile within the combustion chamber to determine if flame is lit.

Thanks again for the input, sounds like one can plan on building a control system if one wants to have a good system.

Again, amp draw is what I would like to know?

Also, how much noise do they make?
Our Suburban heater is so noisy we never use it at night, and most of the heat just goes out out the exhaust pipe. As a suggestion, a Dinosaur board may be modified to make a safer controller with an ignition system and flame detector built in. But, sounds like the system you have works well.

Paul and Mao

[96 Wideglide]

I'm curious how Webasto and Espar can justify 20X to 30X the price, for their identical units .

I'm sure they are a little more refined, probably a bit quieter. I could see them charging 5X more, but up to 30X the price ?

[Captain8]

What I read is they draw about 10 amps with the glow plug and about 1 amp when running. I plugged both mine into the same spare wiring and if I try to start both at same time the voltage drops on the line and they'll get a low voltage error, so I have to start 1 then wait 10 minutes and start the other.

Mine are right outside and we can't hear anything other than the fuel pumps clicking. The airflow isn't very strong and since they're ducted about 5ft it's really quiet inside. Outside they sound about as loud as our propane heaters sound outside (which are a lot quieter outside than inside).

I plan on using an aftermarket controller or just programming the stock remote to a nodemcu so I can remotely control the heaters anywhere.

[Captain8]

After some use I found some issues.
The heat is so hot it's melting my plastic defroster vents.
If 12v power is lost for whatever reason fumes get into the intake and RV gets smokey.
Both exaust ends came off and needed duct taped to keep on.
Get errors quite a bit and need power unplugged to reset.
One of the fuel pumps quit working apparently. So waiting on a new one

[Cougarkid]

Only 50 gallons? I can go through a gallon overnight in my 42’ class A when the temps drop to 25 outside. I can’t count how many gallons I have burned! I always keep at least 10 gallons on hand. Helps that the Rv and the toad (Jeep JLURD) are diesel, too.

On my 3rd season with my $125 8KV Chinese diesel heater. Only thing I have done is blow canned air thru the blower fan to clean it up some.
It is mounted under the fridge, next to the 30,000 btu propane furnace that hasn’t seen use since the install. Side mounted on a steel plate, exhaust pipe sealed to heater with stove pipe sealer. Exhaust goes outside via a thru-hull exhaust (marine style). Combustion air comes in via a clamshell over the tube. Carbon monoxide detector, too.
“Return” air is from under the fridge, just like the propane furnace. Tank is in the basement, on drawer slides on a wall. Pull it out to fill it up.
I bought the 4-port / 4-hose style. 1 port connects to the Rv factory line that runs to the wet bay for freeze control. 2 hoses blow out from under the fridge and aim towards the middle and front of the coach. The 4th hose goes along the wall towards the back bedroom, with a splice and the unused pipe. Heats the bathroom and bedroom.

BTW, I did NOT play with the settings. Just installed it and turned it on.

[96 Wideglide]

Originally Posted by Cougarkid

Tank is in the basement, on drawer slides on a wall. Pull it out to fill it up.

Coach fuel tank too far?

[Cougarkid]

Originally Posted by 96 Wideglide

Coach fuel tank too far?

No, don’t want to tie it in. Last thing I want to do is deplete the fuel for the coach when we are out boon docking!

[moisheh]

https://ww2.arb.ca.gov/resources/doc...ters-checklist

[Captain8]

Originally Posted by Cougarkid

No, don’t want to tie it in. Last thing I want to do is deplete the fuel for the coach when we are out boon docking!

I teed off the generator line for this reason. It'll always leave at least 1/4 tank

[96 Wideglide]

Originally Posted by Captain8

I teed off the generator line for this reason. It'll always leave at least 1/4 tank

Any issues with the generator pulling the fuel from the line feeding the heater?

Could this be causing your faults? Heater needing to re-prime itself.

I've just begun bench testing one. They seem to be happiest with the fuel line constantly full, without air bubbles, from tank right to heater.

[Captain8]

Originally Posted by 96 Wideglide

Any issues with the generator pulling the fuel from the line feeding the heater?

Could this be causing your faults? Heater needing to re-prime itself.

I've just begun bench testing one. They seem to be happiest with the fuel line constantly full, without air bubbles, from tank right to heater.

Nope no issues with fuel yet but I did have a fuel pump die on me already. There are 2 fuel lines going into my genny and I just guessed on which one was the feedand not the return. My genny fuel line is pretty small but I almost never use the genny since I have 800ah lithium, 3000w solar and mostly use the RV for daytrips.

My issues are mainly
E05 which is overheating, which I'm guessing is because I have 2 heaters next to each other as I only seem to get that error when they both are running.
E01 which is low voltage under 10V. Also almost only get this when starting both heaters up at the same time.

I ripped out my dash AC and redid the dash completely. I apparently have huge airleaks so when driving it gets freezing which we run both heaters full blast, one for defrost to heat the windshield and other goes right in the middle to keep us warm. We noticed on last trip that even with both these at full we're freezing. Even though the defrost vents are so hot they're melting the plastic vents (180degs per my flir) when driving they're actually putting out cold air on the far side. Once I find a way to make a replacement vent duct that'll fit the area I'll be able to actually insulate it. Although reflectix max temp is 180 and these things pump heat that hot so I'll have to test how hot the ductwork is.

I have the heaters mounted up high above my generator so the exhaust is piped below it and behind. I'm thinking having them so high in a small place the heat from the exhaust and ducting gets trapped in that corner when driving and its where the intake holes are (there's no ducting on intake) so the hot air is coming in causing overheating. Especially when driving since there's apparently a ton of air coming into there from I guess the front cover and must be pushing that hot air up.
I plan on moving them lower to the side of the generator then putting something like wood to cover that whole area and insulating the entire thing with just holes for the ducting. Hopefully creating some small storage for air hoses and a few tools.

[96 Wideglide]

Sounds like you've got leaks big enough to stick your arm through!

Have you checked down where your steering shaft goes thru the floor?

[Captain8]

Originally Posted by 96 Wideglide

Sounds like you've got leaks big enough to stick your arm through!

Have you checked down where your steering shaft goes thru the floor?

This is my 1st RV and really only time I've actually been in one in motion so I'm not sure whats normal or not so learning as I go. Unfortunately the wife is too afraid to drive it and isn't good at finding leaks which only seem to be able to be found when driving. I was hoping redoing the dash would fix the issue since I removed the dash AC but didn't really help. I know there was big holes on the vent register things which I taped up but apparently that didn't help much so hopefully once I make something then insulate the entire area and insulate all behind the front of the RV it'll fix the issue. I also added R30 all up top by the clearance markers which had like no insulation but it didn't help much. I plan on redoing the entire cabinetry next so i'll be certain its sealed. We do have a leak on the top right corner above the windshield somewhere I can't see but I'm assuming thats the window seal but it hasn't been warm and I don't want to caulk the outside when its real cold. I figured it won't seal very well.

I haven't done too much under the drivers side foot area yet but I haven't noticed anything obvious yet. Maybe I'll check that area out and add some interior insulation this week since its like 10 degrees out and I really don't want to work on the front in the freezing.