The laws differ from state to state. Some states do not require that and ac unit be repair, because it is considered a luxury item. (which when you are 6.5 month pregnant and it's 90 degrees sounds insane, I know). So the first step is to know what the rules are in your area.
As I read this, you say they came out and looked at it Tues, as in two days ago? A repair like replacing the whole ac unit can take over a week. When our rental property ac went out and needed replacing, we had to wait for the unit to come in AND then schedule installation. It took nine days. (Fortunately, for everyone involved, it went out in the fall.) Landlords in our area have about 7 days for major repairs, but there are exceptions...like waiting for parts.
Do not assume that your landlord will pay for a hotel. We did once and will never again - we were seriously taken advantage of. Do not check in and take the difference out of your rent. Unless that is written in the lease or you have written permission, you can be seen as failure to pay rent.
Arm yourself with information, find out what is expected in your state. In Texas no AC is considered hazardous to your health. If it's not repaired in a timely manner, tenants can end the lease, sue or repair it themselves and deduct the cost from rent. But you have to have everything carefully documented.
Call or email (you'll have record) your landlord and talk to him. Find out when he expects things to be repaired.
If it's not happening ASAP and you want to stay, find out what he's going to do to make it right. He may be willing to pay for a hotel. Or do something like we did. Last summer our tenants broke the ac (long story). The part was on back order and would take three days to come in. Summers in Texas are over 100 degrees. So we purchased a window unit for them to use in the living room. Not ideal for everyone to sleep together, but it was the best compromise we could come up with until the part came in.
Find out the rights in your state. Document everything and then proceed from there.
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