Turning Up The Heat

Tweaked the fuel line setup to my liking. Not entirely sure this will be the final design but it's close to how I want it, including the fuel filter. I might fit a quick disconnect downstream of the filter but as yet undecided.

 

Been a while since I updated this thread, due to ill health that I've already documented on this forum. On the final leg now and finished drilling out all the holes in my custom made stainless steel box, for the diesel heater and tank to fit into. Next job is to powder coat the box, before fitting it out. New concrete pad going down outside, that the whole setup will sit on.

 

So I finally got the stainless steel box back from the powder coaters. Went with a light tone green to blend in with the garden. Should hopefully have all the bits ready by tomorrow for a final test fit before it's permanently sited outside on the concrete plinth, ready to connect up to power. After that I just have to drill the hole through into the garage for the hot air delivery duct and it'll be almost complete.

 

Hmm. Now you got me thinking. Had it fabricated so long ago now, I cant remember!! Could well be. Main thing is it won't rust!!

 

So I have finally finished assembly of the heater enclosure. All that remains now is to lay the concrete slab outside (which is being done next week, site the enclosure on it and fit it out, connect up the electrical supply and drill the hole through the wall for the hot air outlet duct to enter the garage.

New rubber feet fitted. These will allow a small air gap underneath the enclosure and should there be a diesel leak, for any fluid to drain out through the pre-drilled holes (more on those later)







Next up was the main hot air outlet duct, that will aid in routeing the delivery pipe from the heater to the outside wall mounted flange. Specially manufactured silicone gaskets will ensure a heat resistant seal between the two halves of the duct. As always stainless steel fasteners used throughout.







Next I had to bond in the three ambient air ducts that will allow the intake fan to draw in fresh external air. Here are the two on the inlet side of the heater case.



Now time to fit the exhaust outlet duct, which will be connected to an extension and a silencer, mounted at some distance from the enclosure to prevent any gases from being drawn back in. However just to be safe, should there be any rise in CO levels, I have a detector fitted in the garage that will alert me of any combustion gases entering the building.

 

Next was the lid, hinges, lock and gas struts.







Electrical supply gland fitted





Rubber seal will prevent the ingress of any water when the lid is closed.





Last job was fitting the insect grille over the drain holes. I cut this to size and painted it in hammerite to prevent corrosion.







And here is the finished article ready to receive the heater, wiring, fuel tank and filter. The two remaining holes are where the fuel filter will be bolted to the enclosure internally.

 

I was simply going to embed a small plastic channel into the slab under the enclosure drain holes, so any fuel leaks will drain off to one side, though we are talking about very small amounts of diesel here.

 

So the concrete slab is done, as is the ruddy great big hole in the garage wall, courtesy of a 92mm diamond core drill bit and a bloody heavy drill. Really chuffed with the end result and no damage to either the render or the plasterboard.

Outside wall, with no cracking or flaking render, thank God. Drilled out and plugged four holes that will retain the screws for the external ducting flange, which I will additionally seal to the wall with an exterior mastic.



Decided to paint the concrete slab black with heavy duty masonry paint. The surrounding path is going to get landscaped in January, so I didn't fancy a bare concrete lump sticking out the ground. You may ask why it is so high. This is due to the differential in height between the ground outside and the floor in the garage. If it was any lower the ducting would have exited into the garage, just above the skirting board. You will barely notice the vent inside, once the grille is in place.



Minimal damage to the plaster inside. Very relieved.



Here's a view of the electrical feed out to the external junction box and where the ducting will come into the garage. All inside a 110cm foot print, which keeps the direct hot air, clear of the bikes.



Some of the ductwork, ready to fit. I will try and crack on tomorrow. Just waiting on some other parts to arrive.

 

So today I fitted the through wall flanges, vent and ducting. Quite an ordeal, as I had to nibble out some of the blockwork to allow the jubilee clips to fit inside the hole, that clamp the ducting to the exterior flange and to the internal vent outlet. The exterior flange is basically two flanges back to back, to provide a boss onto which the ducting that runs through the wall, can attach to and the other one, a means to connect to the heater. These were sealed together with mastic and then more sealant applied between the wall and reversed flange to prevent water ingress. In addition, I added some exterior silicone sealant around the periphery of the flange where it meets the wall to prevent any water creeping behind. The whole thing was then screwed to the wall to secure it in place.
The "fun" started when I had to mount the internal vent. I won't go into detail, suffice to say it took a long time due to some complications but I got it sorted in the end. Very pleased with the outcome.

In case you are wondering there are four screws holding the plate to the wall. The extra two holes were already drilled when I bought them, so I just plugged them with silicone to prevent another possible entry point for moisture.





This is the internal vent plate. There is a white cover that clips over this, which rotates to direct the hot air flow and has louvres to control the amount and angle of the flow. They can also be closed completely, when the heater is not in use, to prevent any wee beasties crawling in.



The hot air vent is well clear of the bikes and once the white fascia is fitted you will barely notice it.



Next job is to fit the interconnecting ducting from the exterior wall flange to the heater outlet then wire up the QD cable to the exterior junction box. After that it's a case of installing the heater and tank and it's almost complete. Light was failing by 3.30pm so I called it a day.

 

It's been a while since I posted up on the heater, so here is where I am at now. The heater is now complete and running. Approximately 1.5 degree temperature rise in 1 hour, so obviously to heat a double garage it's not as quick as a van or tent, where these heaters are normally intended to be used, but I'm not that fussed, as if I want to work in there, I just switch it on a few hours beforehand and it's up to a comfortable temperature by the time I venture out. I am considering a mod to draw air in from the garage, contrary to my original design and am waiting on some parts to arrive from the US. This will effectively then re-circulate the air, as opposed to drawing in a fresh charge from outside, so the heater is not working as hard. On full chat it currently burns around 0.4 litres per hour, so with a 30 litre tank that's around 75 hours of running time at a constant setting, but as of today it's actually consumed 10 litres of fuel in a little over 29 hours, so I'm pretty happy with that. Anyhow enough chat, here are some more pictures.

Exterior junction box wiring complete



Main electrical feed into the enclosure



Internally, this is the quick release connection to the heater.



Fuel filter and fuel lines in place



Internal ducting for hot air outlet and exhaust



External ducting connected to wall flange inlet



Exhaust pipe and silencer fitted. I made up some aluminium stand-offs to step the silencer away from the render and added some heat reflective foil to protect the paint. Now issues so far after 30 hours of running time.



Here's the whole setup.





Last job was to fit the internal vent plate/cover.



Finallly, finished up the integration with Home Assistant so now I can control the heater from anywhere (even when away from home over WAN). It is also integrated with Alexa for voice control.

 

Video of Alexa initiated heater start

https://youtube.com/shorts/D4NCGkLEs7I

Also animated the icons representing the GPIO functions of the heater, so I get a visual indication of their state based on a returned parsed JSONout string. Last job on the list will be to fit a new bespoke silent pump and integrate the text-speech, speech-text functions in HA for full control of the heater, as well as HA send me notifications or voice alerts if for example the fuel runs below a certain level, a timer is active, frost mode was enabled etc etc.