Prolific Sitcom Directors

Such as:
Jerry Paris!

Alan Rafkin!

Both also actors and associated with The Dick Van Dyke Show.

Pamela Fryman, doncha know. Famously directed nearly all episodes of How I Met Your Mother but also a slew more:

https://en.wikipedia.org/wiki/Pamela_Fryman#Television

Plus most episodes of Just Shoot Me!, still working steadily now, a bunch of TV movies too, etc.

Thought of Bud Yorkin because of all those All in the Familys (204 episodes according to imdb); also 69 What's Happening!! episodes.

Rod Amateau directed the majority of episodes of The Many Loves of Dobie Gillis, as well as The George Burns and Gracie Allen Show, The Bob Cummings Show, The New Phil Silvers Show (and eventually finished his career with The Garbage Pail Kids Movie)

Jim Burrows (obv)
Peter Bonerz

John Howard Davies who played the title character in the David Lean Oliver Twist film later became a TV director and producer, and directed episodes of Fawlty Towers, The Good Life, All Gas and Gaiters amongst other stuff

And how many of them are ex-sitcom actors?

Anson Williams!

Jay Sandrich:

Sandrich directed and/or produced episodes of The Bill Dana Show; The Bill Cosby Show; Get Smart; The Odd Couple; Paul Sand in Friends and Lovers; Loves Me, Loves Me Not; Soap; two-thirds of the episodes of The Mary Tyler Moore Show in early seasons and recurring including the series finale; he also directed 100 episodes including the entire first two seasons and the series finale of The Cosby Show.[3] He also directed the series pilot episodes of The Bob Newhart Show, WKRP in Cincinnati, Benson, Empty Nest and The Golden Girls. His last work as a director on television was an episode of Two and a Half Men in 2003.

William Asher!

Directed 110 of the 179 I Love Lucys and 131 eps of Bewitched, plus 27 eps of Alice.

Peter Bonerz

cannot resist saying his name in my frattiest voice every time i see it

(b4 some1 ruins this for me, i know its pronounced like "bonners", please let me have this)

131 eps of Bewitched

Was married to Elizabeth Montgomery, I believe.

Also directed the bonkers 80s horror film Butcher Baker Nightmare Maker.