I picked up the car a couple weeks ago, when it was brutally cold here, and noticed that the heat was not blowing hot air. It was only barely warm, so I mostly just used the defroster/floor setting, and I made a mental note to have the thermostat changed.

 

The other day, I was fiddling around with the heater and pressed the Recirculate button, but it did not light up. However, when I pressed the dash/floor button, the Recirculate button lit up and the heater began to put out very hot air.

 

This is great because the car warms up quickly in very cold weather, but a by-product of using this setting is that in a matter of ten to fifteen minutes, the windows begin to fog up, so I have to switch back to the defrost/floor setting which clears up the windows, but only produces mildly warm air. So my daily commute of over an hour consists of alternating between the two settings every ten to fifteen minutes.

 

Does anyone know why the heater only puts out hot air when the recirculate button is active and if there is a remedy?

seems weird, dunno that I have read of that specific set of problems unless there has been some non-OEM re-wiring of something.

 

the A/C compressor running with defrost is the main thing you need to prevent fogging so, if there's a a/c issue - that 'may' be part of the problem.

 

almost seems like 2 different issues.

 

hope someone with experience with the older cars chimes in.

In my 97 Imorza Outback Sport, I have also experienced the problem with the windows fogging when the controls are set to recirculate, so I just never use that setting, but it still throws hot air when recirculate is off.

 

I cant understand why the air isnt hot in the 98 Legacy unless the recirculate is on.

Most cars will not allow you to use the re circulation setting while in defrost, for exactly the reason that you're stating.

 

Where does your temperature gauge typically read?

 

 

I suspect you have a weak thermostat, preventing the engine from getting all the way up to temperature, which limits the amount of heat energy the heater core is able to transfer to the air passing through it. If it's pulling air from the interior, it's already somewhat warm, and it's much more efficient. But pulling from outside it just cannot keep up.

When I use the recirculate button, the air is instantly much hotter than without it. I mean really hot. A weak thermostat is what I originally thought but it seems like the difference is just to much too quickly.

 

Now that its gotten a lot warmer out, the difference still exists.

 

The temp needle reads just a little below halfway.