The International Cessna^® 170 Association

I'd like to find a better cabin heat control box than the stock one on my '52B. It doesn't shut off completely, doesn't distribute heat nicely, and the dump vent when heat is off is a little small for the larger volume of air from the Lycoming 180. I don't have access to a lot of options to look at and so I'm asking for ideas please. Thanks.

Maybe a cabin-heat valve from a later model 170/172? If you run across anybody with a later 170/172 eyeball their set-up if you can,then check the salvage outfits for that part.You might need to look at some illustrated parts catalogs for later models,don't know if there's anything like that online or not (probably not).
An old 170 News in my collection (#2/97) has an article by a guy in eastern Washington with an IO-360 powered B model who added a VW heater blower to the heat valve for forced air heat. I also seem to remember reading about someone who added a SECOND heat valve to the firewall.

Eric

Heat valves for early 60s 150s (I forget exactly what year) look just like our heat valves except they have a 3 inch opening instead of a 2 inch. I'm planning on changing mine out to one of these some time and also add a second one on the right side. Both would require an approval. Later 170s and 172 heat setups are a lot more complicated than the earliar models and involve ducting inside under the instrument panel

That's a good tip Bruce. The Lycoming needs a 3inch anyway and there is an adapter for changing mine but my valve is not in great shape and leaks alot of hot air into the cabin when you don't want it. Eric I don't need much heat being in WA in the summer and AZ in the winter so I'm not really after a complicated system. I wonder if the dump area is bigger on the 150 box. I'll have to look at one.

I've got the old headliner out and am installing the Javelin tank. I ordered the BAS harnesses today. Besides the new headliner I'll be repainting all the door jambs, interior pieces and the revamped instrument panel also so I'll probably be all Winter with this. Eric I'll have to loose my IFR Instrument to gain a hole for the manifold pressure gauge. Darn!

Dave, in the summer, when I donn't need or want the heat, I disconnnect the scat hose at the firewall and tie it to the engine mount, facing down with the help of a tie-wrap. I hate the hot foot you get from it. JD

I just come across the part number for the 3" heater control valve,
#C450247-2

I don't remember exactly what year this is from but it is a early 150.

Thanks Bruce. I'll look it up in a parts book and see if it will work.

Dave

I have a friend with an old 7AC Champ that had an exceptionally good heater in it, and would get too hot in the sumer. On them old Champs they only had one heat muff that provided cabin heat and carb heat both, unlike the 170. Well he decided he would unhook his cabin heat hose also. However it dumped the heat overboard so fast that when he got carb ice he couldn't get rid of it and it just kept building. He ended up making a safe emergency landing and hooking back up the hose, and it ran fine then. He was a little and telling me the story. But it was a good lesson learned.
Shawn