Heater box refurbishment

While I am struggling with how to fit the windscreen seal (thread) I am going to make a start on something that should be nice and easy and straight forward and refurbish my heater box which is sat on the bench. Can anyone point me in the direction of a good guide (preferably with lots of pictures) or is it very obvious once you get in there? I remember reading a thread on here by someone who had used camping mats to replace seals and I know it has been done lots before but I am struggling to find a write up, possible because it is so basic once you have pealed it apart.

It is pretty staight forward. The box is rivited together so these need drilling out to get it apart.
The internal flaps and the way the hot/cold air is directed are easy enough to understand as is the motor/fan.
There are 2 different types of cores, straight pipes and bent, the elements are different sizes so you need the right one.
I packed all round mine with some rubbery foam so that the air went through the core and riveted it back together.

You can see below the panel I took off which let me get to everything.



There is a seal to the bulkhead and a seal to the inlet air pipe.
I bought new ones from Bearmach or LR Direct, it made life easier to get it all back in, the main seal to the bulkhead is a bit traumatic to get it in the right place and stay there.
I also fitted new resistors so that slow was a bit faster than standard.

Much better than before.

I knew I had to drill out the rivets, that is my plan for this afternoon to start to clean up ready for paint. I also need to test the motor as it is off the replacement bulkhead so is currently un known. I was hoping to flush out rather than replace the core, and I have the inlet and outlet seals already.
It was the internal packing and seals I was unsure of but your pics make it look very basic so I will dive in and see what needs doing.

It is quite basic really. To stop the flaps 'clanking' ahgainst the sides I stuck some rubber mat on one side of the flap (cold in) and the wall (divert air to core) using some heat proof spay on carpet glue.
I was a bit unsure however it's been through a winter and still 'works' as expected (ie the flaps operate smoothly and make a reasuring 'thwock' sound).

Make sure you get the correct length of rivets !! If they are too long they foul the flap

I used camping mat but I don't think I did a thread on here about it but I'm pretty sure I have mentioned it. The stuff you want is soft and warm to the touch , there are cheaper not as good mats out there. I used 2 or 3 layers glued together for the bulkhead seal, used it on the flaps and even made the sound deadener under the gear levers out of it.

Well I have completed the heater box rebuild, you were all correct that s is very straight forward and simple once it is apart. Everything was painted



The heater matrix was repacked with neoprene tape and the vet flaps were resealed with neoprene tape as well.



Lots of rivets later and it is back together and for good measure I have seam sealed the whole thing to try and get as much warmth as possible out of it. I know this will make future disassembly more challenging but the last time I did any work on it was 10 years ago so I sure it will be fine for a good while yet.