Are tryingto remove all the paint or just loose ?

Uhmm....well we ned to paint the wall...! So we thought, lets scrape it and then paint it over. The paint is kinda loose at some points..! So...we think to just take off at least 70% of the paint. We have been told that we need at least 3500 psi..is that correct.?

It is a brick wall so you need not worry about wrecking anything so whatever pressure you use even a very high one such as the 3500 will work.
Start about a foot from it and if it isn't coming off yet then move in closer till it comes off if you get to close seeing as its brick I really doubt it will blast the brick off.I know if it was wood you would need to be really careful.
Use a fan type spray or tip don't use a fine point or needle tip.

You can remove paint with 2500psi and have less chance of damaging the brick. You also may want to get one the tips that rotates as they make the job much faster and less chance a damaging the brick. You should wait at least 5 good clear warm days before painting the brick after you power washed it.
There are many products to paint brick and you should check with your local paint store to find out the system they reccomend.

Thanks guys....! We live in ARUBA and we don't use bricks here. We use 6" or 8" concrete blocks. The weather is not a problem...cause it never rains in Aruba..is the slogan..lol!
My question was...how much pressure do I need so the paint will come off. We are going to Miami next week and need to buy a pressure washer...so how big of a machine do I need to buy...???? I see sssooooo many and I'm confused which one to buy! I see the electracle ones from 1200 psi, and the motor ones 2500 psi..!

Again thanks guys

When you get to Miami call the local Duron paint store and they will be glad to help you with the correct power washer. The phone number is 305-468-9215