Heater issues

[Blueford1]

Hello All,

The heater in my f100 is always blowing. It always starts to heat up after the engine is warm. I installed a new thermostat and nothing has changed. Any ideas?

Thanks.

[390FE1972]

I would check the in-line valve in your heater hose first, they often get rusty and won't open and close properly. Here is a thread that talks about the similar problem to yours: https://www.fordification.com/forum/vie ... =6&t=96179

Let us know if it is working or not, I would suggest that you pull it and make sure it looks like it is working properly.

Regards

[Blueford1]

You were right! The heater valve was stuck open.
Thanks so much.

[390FE1972]

Glad to hear you got it fixed!

[Blueford1]

Ok. So I thought that replacing the in-line valve and the heater hose worked, but it did not. The heat just blows when I'm actively driving down the road. When I stop at a light there is no heat. Any ideas?

Thanks.

[DisneysPatB]

https://www.dennis-carpenter.com/trucks ... -fresh-air.
The "foam" seals deteriorate with time. This is what you need to fix that. I am doing this in mine right now.