Fetching projects from project server through REST javascript

I have written below code to fetch all the projects, however its not working after $.ajax call. However, strange thing is, if I put a debugger in developer toolbar and debug it for long time (including jquery file) before hitting F5, it works fine and brings all project names. Below is the code.

I replaced project server url with sharepoint list REST call and it works fine.

function getProjects() {
$.ajax({
    url: "http://chnsharepoint02/PWA" + "/_api/ProjectServer/Projects",
    method: "GET",
    headers: { "Accept": "application/json; odata=verbose" },
    success: function (data) {
        success(data);
    },
    error: function (data) {
        failure(data);
    }
});}