How long do I have to wait to get a replacement stove from my landlord?

I recently moved in a new apartment. On the 2nd night in, I tried to warm up left over pizza in the oven. Less than 5 minutes, the fire alarm went off. There was no fire or smoke. Thinking it was a fluke, maybe the stove needed to be cleaned. The next night, we tried it again after cleaning the stove, the carbon monoxide alarm went off. So we reported it to our super. He sent his maintenance guy over and said there was no leak. Not convinced we called PSE&G and they came and inspected. There was a carbon monoxide leak and it came from the stove. They advised us to replace the stove since it was old and beyond repair. We immediately informed our super and he told us that they would replace the stove on the weekend. That was more than a week ago. What is a fairly reasonable time to wait for the replacement? My super is a bit flaky since he gives us a different story all the time. First was he was going to replace it right away but now he's saying that he has yet to hear from the landlord. Should I withhold paying rent until I get a replacement? Also, I suggested to the landlord that I buy the stove and have it installed, then he would just refund the cost. I already sent him 2 emails but he has not responded. Please help. Thanks.