Van heating Queries

Finally connected up my heating on my splitty basically the ducts/pipes were missing between the fan housing and heat exchangers + between the heat exchangers and the body. Heat is now coming through but there is a lound baffle/exhaust noise now in the front of the van - any ideas? I don't think I am getting exhaust fumes in the van as I cannot smell anything however I will double check with a carbon monoxide tester, my thinking was I have an exhaust leak somewhere and the noise is travelling up the heater tube, the noise gets louder under load. Any ideas or similar experiences?

The other problem I have is the heater control in the front, mine is a (63) single column between the kick panels and is currently open to put heat out by my feet, I cannot seem to close it and direct heat to the screen. How does it work as I cannot find any info, the little handle thing does not move which maybe down to the respray but I am not sure how it should move i.e. up or down or right to left. Any ideas or experience on this one?

I recon your right with the sound traveling up the pipe, best to doa test as you said to be sure.

Yep carbon monoxide alarm went off straightaway - back to the cold for me! Surprised how much noise a leaky heatexchanger makes. Anyone got any decent ones lying around - will give the going rate for them.