Interior heater / fan housing

[colinw]

Has any any experience of removing the housing the heater matrix and fan?
I ask this for I do not any (hot or cold) air flow through the interior dash vents nor to the windscreen. Removing the large flexible hose in the engine bay from the metal duct, next to the windscreen wiper motor, which feeds the air into the top of the heater box and blowing air into the duct (using the powerful vent from my workshop dust extractor) there is no airflow through the system ie through the dash side vents or through the flap in the heater box to give air flow near the feet. It looks as though something has collapsed blocking any air flow.  The system used to work but has now failed.  Removal of the housing seems the way forward and at the same time re-furbish the heater matrix and re-furb a noisy sluggish fan..
Any help much appreciated.
Thank you.
Regards
Colin     

[makemeanoffer22]

Hi Colin, removed the heater housing from my Flavia fairly recently. Held in place with four bolts from memory 6mm, the ones at the front fairly easy to get to but those at the rear against the bulkhead a little more difficult . I had the seats out at the time which allows you to lie in the footwell and work upside down. Bolts at the bulkhead had corroded following a leaky unit but can be accessed from the engine bay and penetrating oil applied, you will find the end of one just inside the  metal cowling that the flexible inlet pipe attaches to( within the engine bay ) and the other in the opposite location near the wiper mechanism, can also be drilled out if needed. Replaced mine with stainless bolts. Unit drops out once all other connections disconnected and then remove the top panel of the unit to reveal the matrix and large flap which controls airflow.
The flap mechanism on mine had seized but easily repaired and then i replaced the matrix with one i bought online which was almost the same size, although the outlets were in different locations i managed to route the water pipes to suit. Tricky getting it back in with the foam gasket in the right position so glued in place before refitting. I think i also removed the clutch pedal to allow access to the cable fitting which is rather awkward. Good luck, regards Nigel.

[colinw]

Thank you Nigel
Lots of detail, thank you.  My fan housing sits quite low quite near the g/lever housing and looking at the two solid pipes extending into the engine compartment they are quite long and wonder if there is a problem lowering the housing and getting the pipes through the bulkhead/firewall? Tilting the assembly is the answer I suppose.
I shall save the job for winter courage.  Might reverse the water flow with a temp header tank to flush the heater matrix first.
thanks again
Regards
Colin