Dont have a lease ? and land lord wont fix my heat?

i dont have a lease but ihave been living in this house for 10 yrs when my parents have moved out i took over the rent and my land lord never gave me a lease to sign ... and now my heating systems is broke and they had some one come out and look at it and they said its going to cost to much to fix it and that they arent going to fix it now and i live in virginia and its been cold i have 2 small children and im pregnant and we have been use kerosene for a source of heat which isnt good for my kids or me but i have to keep my family warm some how i was just wondering being i dont have a lease is there anything i can do about my landlord not fixing my heat .. please and info would be helpful thanks