Poor heater


I've got a H reg sportrak that's just had the headgasket done, before that went I noticed the temp gauge hardly moved( and still dos'nt) and the heater is not the greatest(it gets warm fairly quickly but is never what you could call hot). I have'nt had the car long and have'nt owned one before so I'm unsure if this is normal.
Could the thermostat be faulty, would this cause the chg to blow? would like to avoid that again if possible.


Temp gauge should move half way.
If the head gasket blew due to over heating then it could do a repeat. Did the garage check the cooling system for circulation? A 'H' Sporty is elderly. At that age the engine radiator is usually full of grime and the tubes will be blocked.Does the radiator coolant need frequent filling?
Try touching the top of the radiator whilst the engine is hot.The heat should be same as that through the heater matrix. Alternatively look towards the rear of the engine, left hand at back, there are two pipes which supply the heater matrix. Touch those pipes: are they as hot as the radiator, or as hot as the heater. If the heater is significantly cooler than the pipes then suspect a coolant blockage inside the heater's matrix.