2 problems till now

[KiaDxb]

i am having a very strange issue wid my car.

1st when i switch on the heater, there is no heat only cool air so i fill up the gas and the same issue

2nd and last even when my car doors r closed there is a hissing noise coming from the door. can i fix this

your early reply is thankfull

[KiaDxb]

Check if the heater has been unplugged by previous owner or the heater switch is working fine. As car heater uses the engine heat thru radiator and heat up the cabin, no much A/C or A/C compressor job. check the switch its gone bad and not switching to hot mode.

About hissing noise, identify the side its coming and then remove the door inside beading and refix it nicely. If needed fix beading with little bit of silicone inside and it will seal that air leak, easy.