Landlord hasnt fixed furnace i havnt had heat yet this winter its 6 degrees out?

it all started in november i thought my propane was empty spent 600 on filling it they said still 10%in there so furnace problem then it would kick on normaly for around 10 min then trip the limit switch about a month went by with my landlord knowing about it and paying dec rent still no heat now jan payin half the rent ,end of jan now she had a guy she know come over for approx.7-8 hours and he says we should be all set but the furnace still does the same thing, now its 6 degrees out i had a water line break ,had to stay in a hotel for a night ,and bu another heater,my elect.bill was around 500.00 from keeping our stove and having elec,.heaters on all this time,she has asked my wife if we had the rest of the rent for the month also now me personaly i think my rent is paid for the month and should call a repair man myself i already have they said its the heat exchanger wat should i do rents do again and havnt had heat all winter?