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Hello all
Been working on getting my restored Harrison Fresh Air Heater and restored Ranco valve going in my ‘50 Truck

It is freshly restored with a new heater core and 12v motor; additionally I changed the 160 degree thermostat to a 195 for winter
Everything is running correct I think
During my swap of the thermostats today, I disconnected the heater lines to make sure I had no clogs and ran the hose through it
First through the Ranco to the heater core; I adjusted the knob on the Ranco to allow more flow and it worked
Then I disconnected the Ranco valve and ran from the heater inlet to the outlet hose (going to the water pump)
Both tests were good and no clogs
Buttoned everything up and went for drive
At all speeds, low, med, and high, no hot or even warm air
Got home and checked the heater hoses
Hot going on from the thermostat housing and Ranco and hot coming out of the heater outlet to the water pump

The motor is spinning counter clockwise which should be drawing hot air from the heater core

Any thoughts are appreciated
Ranco
heater hose
Restored Heater

I would try bypassing the ranco by joining the two hoses together and see what happens,that way you should have full heat .

Thanks Kevin
I did that and it worked. Kind of bummed on how my newly rebuilt Ranco wax the problem

If you don’t mind not having original ,you may be able to get a aftermarket valve that will work .The trick would be to find one that worked with the original knob in the inside ,if I remember right the control on the inside is a turn knob instead of a push pull.Someone has used theses before look through some posts to see maybe someone posted the valve they used

I would check with the guy that rebuilt the Ranco . He may have some ideas. You have a beautiful heater and it should work as new. If it is not too much of a job for you I would run the hose from the water pump to the Ranco heater valve inlet. Then if you have an extra heater hose laying around run that hose from the heater valve outlet back to your water pump. Fill with coolant making sure you have air out of the system . This will bypass the heater itself and let you test the valve only . I would set the valve to the open or Warmer position . Start the engine and bring up to temp (make sure no air pockets) . If working correctly the inlet heater hose temp right next to the Ranco and the outlet hose right next to the Ranco should be nearly identical in temp . If you have a heat temp gun that would be the best . If not the old hand on the heater hose test should work. They should be nearly identical in temp. I think you said you tested the Ranco valve but to me it seems like you are not getting flow thru your valve as the evidence shows when you bypassed it. Good luck . Should be easy to get this solved.