In the short term, you'd be wise to get a genuine Hakko element & use genuine Hakko tips.
Then save up for a FX-951 (one heck of a bargain here in the US). Once you give this one a go, you'll wonder why you ever wasted your time & money on your current setup.

Seriously though, your iron is the one tool you shouldn't buy cheap given how much you'll use it. Desoldering stations, preheaters, and hot air stations OTOH aren't used all the time, and the less expensive Asian products make more sense.
This ^ is assuming it will take you awhile to save up the funds for a FX-951. If not however, just get the FX-951 and don't waste another cent on the Yihua 853D (you can still use the hot air section).