Feeling a light amout of heat inside?

[legaspi89]

When I was driving my car the other day. I feel like if the heater was lightly on and I didn't have the heating or cooling system on at all that day. My brother who was in the passenger seat said he felt the heat coming from the upper part of the floor. What can the problem be?

[fdryer]

Well, for one thing, engine heat always radiates back through the firewall and the heater core can never be shut off as a shut off valve doesn't exist so hot coolant is always circulating through. The key to keeping heat from entering is using the temperature selector dial/knob to adjust a temperature blend door; this door selects how the HVAC box flows outside air through the a/c evaporator coils, the heater core or both. Usually its not bothersome for most but selecting the coldest temperature closes off air flow through the heater so incoming air isn't warmed as it flows through the heater core. All outside air will flow through the condenser coil whether the a/c is on or not.

[legaspi89]

You always pull through fdryer. I'll definitely trying adjusting the heater to colder temperature. Doesn't it bother me that much. But I just like to have a good maintaining car. lol
Thanks again.

[born again]

The cable is actually adjustable where it connects to the temperature control flap. If you still get heat at the minimum setting you may need to adjust the cable to completely close the flap. You should feel a bit of resistance in the knob as the flap closes.