Zoneline

my GF has two heaters Zoneline who stopped working at once. it makes sounds really strong and does not disperse the heat and makes other sounds as normal as the fan works but only blows cold air.

Check power on terminal 2 heating elements by a voltmeter
If you have the power, this means that the heating element (s) damaged
If there is no power, turn to the son, fuses, adjusting the thermostat
regarding the fan noise, it is necessary to clean (and fan filters)
success