Heater problems help!

[V8chick]

I have a modified vr commodore sedan, which was once a v6 and now has an vr ss commodore v8 engine in. The problem I have is that I have got the air conditioning up and running again (cold/hot flow). However, the heater gadge that operates the speed of air flow does not work on high, it only seems to work on low,2,3. The other problem I have is that the only air vents that are functioning effectively are the ones that distributes air to front floor area and practically zilch from the other vents. Does anyone have any idea what it could be that is causing this problem and what it would take to correct this problem. The thing that is most frustrating is that I would really like the front windscreen demister vents operating.

[sik_vr_statesman]

hey, i dont know if this will help, but this happened to my sisters car as well (vn) and it was when i had the dash apart i'd knocked a hose off somewhere, so if u've had the dash off, it could be that so just find the one thats off and put it back on.
hope this helps

[samovp]

Sounds like the resistor for high speed on the fan is burnt out which is pretty easy to replace and also the vacuum to the level selector hasn't been hooked up after the new engine install.
The small vacuum hose comes through the firewall with the heater hoses.A giveaway is if you turn the level selector next to the radio and you dont hear any air noise as it should direct vacuum to the respective doors the vacumm hose is not hooked up.

[bobbyd]

sometimes the floor vent control leaks and wont let upper vents switch on, replace it near the heater box, my kept going to floor vent on accelaeration, had small vaccuum leak in this controller

[V8chick]

Thanks for your advise guys. I've now got it all going, works on high speed and all air vents are working perfectly. (High speed relay faulty-replaced relay and some hoses werent connected correctly).