Frank Lampard, Jose Bosingwa, Branislav Ivanovic and Florent Malouda were all on target for the Blues as Andre Villas-Boas retained his 100% record in pre-season.
Villas-Boas gave goalkeeper Petr Cech his first start while Patrick van Aanholt and Fernando Torres also started.
Chelsea dominated from the off with John Obi Mikel heading wide of the target, with Bosingwa having a shot saved.
Nicolas Anelka also saw two shots blocked while a penalty appeal from Torres was waved away.
John Terry then saw a header ruled out for offside before Lampard finally opened the scoring after 37 minutes, the England midfielder slotting home from the edge of the area.
The lead was doubled shortly after the interval as Bosingwa's long-range strike was pushed onto the post and in by home keeper Pattarakorn Tanganurat.
The third soon arrived in the 52nd minute as a neat exchange of passes involving Ivanovic and Josh McEachran allowed the former to fire home.
Villas-Boas rung the changes with victory effectively assured but there was still time for Malouda to fire home after being picked out by a lovely pass from Mikel.
Source: PA
Source: PA