Air Conditioning - Newbie!! Please help!

Hi, im wondering if someone can help me!

Im from the UK and have a portable air conditioning unit. After being on for around 10-15 mins the "coolness" stops pumping out and the AC unit goes silent. The fan still pumps out air but it seems to be warm air, and it will do this for around 25-30 mins before the unit starts up again and the cool air pumps out.

Is this normal? As the AC unit is actually making the room warmer because of the warm air it is pumping out the majority of the time.

Thankyou in advance!

Is this a newer unit? Older?

Sounds like the compressor is shutting off on you, it either is a low charge, or dirty coil on the outside coil.

I had a Window Unit do the samw thing if the outside temp was above 85 it would start and stop if it was below 85 i would work fine. start with the coils take it out of the window and take it outside on the driveway remove the outer cover of the unit you should be able to hose down the coils try to avode the electrionics also clean the fan and the rest of the unit with a damp rag give the fan some oil to leave the unit open in the sun to dry out if you plug it in with it still wet lets just say you won't forget to do that again :D

Is this a newer unit? Older?

Sounds like the compressor is shutting off on you, it either is a low charge, or dirty coil on the outside coil.

This being a portable, how do you get rid of the condensor air ??