I have "overhauled"/"refurbished" my heater box (HB) 3 times to the point of it's working increasingly better each time. Now it seems to work as intended. (Yes, it took 3 times. I am setting new records for decreasing times required to remove and install a HB.) Seals, bushings, flaps, heater valve (HV), Bowden cables and adjustments, flushed HB radiator, epoxyed cracks, lubrication, lever functions, misc. adjustments, etc. All seems to open, close, flow, blow, defrost, and function exceedingly well. 3-speed fan works swimmingly.
However, with the temp lever on COLD (HV closed) and the flow lever on HEAT (allows air into the footwell; HB radiator flap closed), the air from the HB into the footwell usually is uncomfortably warm (sometimes hot; occasionally sorta/kinda cool; not desired in summer). I realize the HEAT flow lever on OFF setting is not designed to completely stop outlide air from going through the HB radiator but; rather, the air mixes with cold air from the cowl. (Additional info: With the temp lever on HOT, I can cook a beef roast.)
1. In the COLD setting, shouldn't cowl air eventually (rapidly?) cool the radiator if the heater valve is closed so pass-through air to the footwell is not heated? Seems so.
2. Any explanations for the aforementioned uncomfortable (at least in the summer) warm air? I got none.
Thanks to all of you who have contributed so much HB information to 2002FAQ. Such info has been exceedingly helpful during my Adventures into HB Refurbishments.
Larry