Holmes Quartz Heater HQH369 keeps shutting off

i know what you mean some old heaters can be a charm of warmth you can find a new one or repair parts here www.discountbargainprices.com

I have this same model doing the same thing. In my case, it starts fine but after a minute or so I can hear the fan cut out. I'm pretty sure it has to do with the fan not moving enough heat away from the sensor (high limit-safety). Either that or the safety is bad. The safety would be the easier to change out so I am starting there. Good luck!

Replace the controller thermostat.

They are the same thing. Quartz Halogen Lamps

These heaters were not designed to be serviced in the field. If it's not over a year old, it may still be in warranty. Contact Holmes through there website www.holmesproducts.com for more info.

These heaters do not have off the shelf replacement parts and were not designed to be repaired/serviced in the field. But, you can return it for repair. Go to www.holmesproducts.com
for more info.

have you checked your filters

I had the same problem. this is what i did. unplug the heater. removed the plastic panel to expose the control panel where the blinking light is.  Removed all the dust and cobweb build up, then using rubbing alcohol, wiped the white residue that was on the green circuit board. I did this 10 days ago and the heater has been working fine since then. chaz  

There is no Filter On this Model. Check to make sure there is Dirt in the Flow way of the two towers. if that is not it the back up fuse in the heater is going bad.