samsung windfree question

im not sure if i just don't get how the thing works, but im wondering if there's a way to have it act like an actual heater. what i mean by this is, when the thermostat reaches temp, it tells the furnace to stop pushing warm air and the system turns off until temp is below. my heat pump seems to heat just to a degree below (unless the thermostat is wrong) and it keeps it a degree below and just runs constantly. like I genuinely don't understand this and my electricity bill has been like $550 for an apartment because these damn things never stop. help!!! people really think this is efficient heating??? I mean I'm in the northeast and it was -11 outside when I woke up but....if it doesn't work why am I meant to rely on it then?

edit to elaborate a little more on the severity, my aunt owns a 3 bedroom, 3 story house, she pays $150 for electricity in the next town over. also yes I am running it in eco mode. I have two in my apartment that run constantly in eco.