Can I use My HPS now? Without Air INTAKE?

I have a 400watt HPS..I have a fan sucking air out..My temps are low 80's..

I will be getting a 80cfm fan in a couple of days for passive intake.
Right now im sucking the hot air out using a coo-tube + 170cfm fan.

WILL THIS BE OK FOR 1 WEEK OLD PLANTS...BABIES WITH JUST 1 SET of Leaves?

I have cfl on them now but want advice so I can switch my hps on.

If i do this I will be removing the cfls,and throwing the hps on them..

Would it be ok if they ar 82F with the HPS?

Your plants should be fine if the temp doesn't get over 85 degrees. However, favorable temperature for cannabis plants to grow in is 73 degrees. I would say if you don't have more than one CFL, to go out and buy a few more to raise your seedlings into adolescence. Than switch them to the HPS. That's one route. Another would be to get some more fans circulating air, or an air conditioning unit works well to but drains moisture from the room. Hope if helps.