1995 Ford Escort

Heater problem
1995 Ford Escort 4 cyl Front Wheel Drive Manual

I have a `95 Ford, Escort, 1.9ltr.
I have replaced the thermostat and temp. Sending unit to the guage. Tha heater blower fan works fine, but I still get no heat. When the car gets warmed up, I get a small amount of heat for a very, very short while. The engine gets hot in the summer time at an idle. Do you think this could be the cooling fan switch?I do my own work, so any advice will be appreciated. I don`t want to spend $40.00 on a switch if this is not my problem.
Thans, Andy
Andy Stewart
January 21, 2009.

Andy, with the engine hot, running, and the heater in, are both heater core hoses getting hot?