My comments on using these heaters:
1. Waterproof the heater control board using Servisol Plastic Seal 60 or equiv. (remove board and mask the connectors - taking care not to damage the motor Hall sensor).
2. If there isn't a main wiring connector then strain relief the wires using hot melt glue where they are soldered to the PCB.
3. The main harness connector (connect the heater to the control/pump/power) sometimes isn't properly sealed (see pic).  They use automotive connectors with wire grommets and internal plug seals.  Sometimes there are no seals installed at all and, even if they are (see pic) they haven't installed blanking seals on the unused contact locations (leaving an open channel straight into the centre of the connector). Seal with PU or other non-corrosive sealer.
4. Tank bottom should be above heater and the pipe shouldn't have any upward sections.  You must use the semi-rigid pipe for the section between pump and heater (soft-wall pipe will dampen the pulses from the pump that the heater relies on).
5, Prime the fuel system with the heater pipe end disconnected (to avoid flooding) to remove ALL air bubbles in the feed pipe.  Most controls have a priming function available (hold OK and down arrow buttons).

Mine arrived a few days ago too and looks to be very well made. Excellent value for money and cant wait to get it fitted and try it out


The air intake should be taken from outside the cabin for various reasons but primarily safety to prevent any possible CO build up should an issue occur and also to separate the combustion system of the heater from the warm air/ breathing space air.


Plenty online topics you can read on this.

My diesel heater arrived today


I assume this will be ok to mount on its side as glow plug looks to be in a similar orientation with exhaust out the side or the bottom


There are two pipes, one is for air in take and the other is exhaust. Obviously the exhaust needs to be vented outside , but does the air intake need to be vented to the outside, or is it ok for it to be left inside the cabin?

Ross is correct, I use the control panel, there is a remote for it somewhere, either way the heater goes through the cool down cycle including restarting the glow plug and pulsing fuel through the burner to blow off soot.
The 2ltr fuel tank sits in the glove box, the heater runs for about 18 hours on the lowest setting using 2 litres.

I've been told that you need to operate these heaters using the control panel rather than just switching off.  The heat exchanger gets very hot and from what I've heard,  just cutting the power without going thro the run down cycle can let heat get into the circuit board and fry it.  You can do a rapid reboot using a power switch without too much issue  - for instance if priming or following a lock out - but if you don't plan an immediate restart it needs to run thro the cooling cycle and shut down.  Its a bit of a hassle and can take 3 or 4 minutes,  but the efficiency and output makes up for a minor delay in shutting it down.

Steve,


I just seen where you fitted the diesel heater on your Otter maintenance log. 
Where have you installed the diesel tank?
Is the on off switch on your dash or are you relying on the remote control?

Yes, if you remove the cover to check where the glow plug is before installation you'll be fine.
I used two insulation gaskets to reduce the heat transfer to the metal plate, this isn't necessary, I was erring on the side of caution.
My exhaust is run through the cabin hence the twin wall pipe and stainless silencer with the drain hole sealed. I also have a carbon monoxide monitor which is advised, it has not gone off after about 30 hours of testing. I will not be running my heater during sleep overnight.

Mine is on its side - starts and runs no problem.  Exhaust runs under the engine to it's silencer so warms it up on a cold morning.  You don't need any special outlets through fom/grp provide you leave some clearance around the exhaust outlet (the supplied mounting plate covers/seals the hole).


The device is designed for through panel installation - the exhaust shouldn't be run inside the cabin area for safety (fumes, heat and noise) any more than you would run the engine exhaust through the cabin?

Hi Steve, when turning the heater on its side I take it that the exhaust and inlet pipes exit on the side? it runs fine like this and only the glow plug needs to be moved to the top position? Is this correct?
I notice the cheap prices are valid through to the 7th January so I think I'll take advantage too.

Sounds good.
If you put the heater on its side as I have, the glow plug has to be at the top.
The power lead on my heater was at the 'wrong' side, it turned out the glow plug was opposite, it was easy to read route the cable to come out on the glow plug side as I needed, then swap the blanking plug etc.

Thanks Steve,
I've just ordered a 2KW heater with all the fittings including through hull exhaust & extra pipe & elbows for about £70.  So that will give me something to do while I'm off on sick leave :-)

Al, these heaters were on sale from AliExpress last week, I paid £54 for a 2kw complete kit.
I would upgrade to the better exhaust pipe, the twin wall stainless bulkhead exhaust outlets are not that expensive as are the 2 litre compact fuel tanks.

I've fitted one to the otter, it's just done 18 hours on 2 litres of kero.
The exhaust is the slightly tricky bit, I would recommend the double skin ex pipe and the same fitting you see in Ross's photo. I've just bought a 2kw version which is more compact and lighter than the 5kw, I would recommend that for a surveyor although both will work.

Photo of our thro hull fitting.  Camera was on a skew but the outlet is horizontal.

The last Chinese unit I bought came with a complete fitting kit and optional thro hull exhaust stub suitable for GRP.  This was double skinned stainless and very little heat gets through to the mounting points on the hull but I don't know how foam would tolerate it.  The actual exhaust pipe gets very hot and needs to be supported to prevent vibration resonance.


I've fitted  4 Webasto and 3 Chinese units so far and the Chinese ones have been a fraction of the cost and much more highly specified with a full fitting kit including fuel tank.  Depending on where you fit it, your insurers might require an automatic fire extinguisher.  You will need a swan neck on the exhaust to prevent any water getting into the heater !  I know its obvious,  but don't exhaust into the plenum of get combustion air from it either !      Be aware of petrol fumes in the craft and not just near the fuel tank - that's a big potential risk.    You may need to fit a spray shield over the outlet !  Just a few ideas :-)