Night Heater (Eberspacher / Webasto)
It became clear that we could do with some sort of heating in the back. The ambulance was factory-fitted with an Eberspacher B3L petrol-fired air heater, very nice but not in working condition when we acquired the vehicle.
It turned out to be beyond economical repair - the motor was totally seized (replacement part cost more than a new heater!) and the body was corroded - the exhaust port half snapped off just removing the exhaust pipe:
So, after a LOT of searching (petrol ones are quite rare) we came across a VW breaker selling an identical unit - brilliant! It should plug straight in, saving lots of hassle. We hit “buy it now” and waited. And waited….
…eventually, it turned up, and the outlook was not brilliant:
There was every type of wire in there (automotive, mains flex, speaker wire, doorbell, one battery lead with terminal, curly telephone cord…), plus an entire fusebox, a lump of wood, a split charge unit that looked like it had been living in a flower pot, sparky tape, sticky tape, masking tape, bad crimps, choc blocks, scotchloks, basically everything except the proverbial dead budgerigar. Still, the seller had said it was “tested working” so I set to and untangled it, taking the “easy” option of just unplugging the heater from the rats nest (thankfully the OE connectors were intact) and plugging it into the ambulance. Aaaaaand…. nothing.
After a lot of farting about it turned out we'd been sold a dud, the controller had been full of water at some point and the internals were clearly damaged:
However, even substituting our controller didn't kick it into life. At this point I ran out of goodwill and sent it back, we'd paid a fair bit for it for the benefit of “convenience” and it was no longer convenient.
After a loooong delay, the seller took it back and then after another loooong delay the refund arrived. Not impressed.
So, after a further trawl of eBay we found a newer Webasto ST2000, that took a little more fitting but ultimately worked lovely and uses less power (~35W compared to ~50W for the Eberspacher):
There's also an issue of ducting - the original install has a big duct coming up through the floor just about where the bathroom door is, not ideal. I made a new lid of the heater box that brings a vent directly out of the heater lid just near the corner of the new bed. A steel plate blocks the old hole in the heater enclosure off, and an aluminium plate (actually the offcut from the roof vent hole drilling) was turned down on the lathe with nice tapered edges and slipped under the lino to drop into the hole in the floor.
Finished floor vent at end of bed:
As the controller knob was slightly borken I used a switched potentiometer of matching specs to turn the heater on & off from the up-blinged control panel:
The heater install has been modified later by using a swirl-pot in the fuel return line to solve pickup problems.