Edit, V2 now below as well.
Here’s a 3d print file I drew up for an inlet adapter for 5kw (2kw – 8kw) Diesel Heater units. This allows connecting of 75mm Ducting (normally supplied for outlet only) to the inlet side of the heater unit without removing the inlet screw cap. The inlet screw cap acts as a debris screen and also holds the lid on the unit and should remain in place on all setups.
Adding ducting to the inlet side is ideal for recirculating room air through the heater unit (most efficient way of heating) when the unit is located outside.
It’s very basic, it pushes on and fits snug. I have fitted one to my heater and it works great. If anything it could a tiny bit bigger on the outlet just to make the 75mm ducting a little more snug. If you have someone that has a 3d printer it’s an easy print and won’t take long or use much filament.
If you don’t know someone with a 3d printer they are available on the likes on eBay, see my spares page
Also check out my CDH Calculator
Version 1

3d Print File – CDH Inlet 75mm Ducting Adaptor (5KW)
.stl file, zipped
Version 2

3d Print File – CDH Inlet 75mm Ducting Adaptor (5KW) V2
-Added a lip around where pipe slides over to help make it a a little tighter
-Added 4x small notches inside to help make a little tighter onto debris screen
.stl file, zipped
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