Strings and neck are a balanced system. Change the strings and the balance can shift, even if you used the same gauge.
Work through these causes:
- Heavier strings: more pull on the neck means more forward bow and higher action. A small truss rod adjustment usually fixes it.
- Strings not settled: new strings stretch over the first day. Retune several times before judging the action.
- String not seated: check that each string sits down in its nut slot and saddle groove. Press each one in gently.
- Saddle movement: on some bridges, saddles shift or tilt when the strings come off. Check their height.
- Bridge tilt on a vintage-style tremolo: a heavier set can pull the bridge forward, changing string height. Adjust the springs to rebalance it.
- Weather: acoustics in humid conditions can swell, which raises the action.
If you didn't change gauge and the action is still high after the strings settle, the guitar may simply be due for a setup. If you prefer an easier feel, consider a lighter set such as S942 in Power Wound Nickel or P1048 in Phosphor Bronze.