Could those more familiar than myself with Seasons One and Two of Barney Miller tell me if Chano appeared in all episodes, or if I recall, were there several episodes in which Chano was absent? If anyone can help me out, I'll be eternally grateful - this is very important to me, and it's been on my mind for some time now. Thank you!

I want to know why Chano left all of a sudden.

Sierra left to star in another show, also created by Danny Arnold, called "AES Hudson Street". It tried to capture the "Barney Miller" vibe in a hospital setting; it died after only two or three episodes.

Two decades later, Arnold reworked the show; now it was called "Stat". Sieera was no longer involved, but the premise, and even some of the character names, were the same. Once again, it lasted about three episodes. It was Arnold's final network series.

Could those more familiar than myself with Seasons One and Two of Barney Miller tell me if Chano appeared in all episodes, or if I recall, were there several episodes in which Chano was absent? If anyone can help me out, I'll be eternally grateful - this is very important to me, and it's been on my mind for some time now. Thank you!
Chano was in every single episode from the first 2 seasons, except "Experience" and "Stakeout", both from Season 1.

Sierra left to star in another show, also created by Danny Arnold, called "AES Hudson Street". It tried to capture the "Barney Miller" vibe in a hospital setting; it died after only two or three episodes.

Two decades later, Arnold reworked the show; now it was called "Stat". Sieera was no longer involved, but the premise, and even some of the character names, were the same. Once again, it lasted about three episodes. It was Arnold's final network series.
AES Hudson Street lasted 5 episodes - it aired from March 23-April 20, 1978. I wonder if any other episodes were filmed but never saw the light of day.