Some writers think all stories where there is a bunch of people talking the whole time are all the same. They don't see much difference between a full length play or television episode. When they see a show where people talk the whole time they just assume it's made of the same basic stuff. While these different media do have a lot in common in that the conflict is mainly interpersonal, they are different in other ways.

Short Vs. Long

The obvious difference between episodic TV shows and full-length stage plays is running time. Hour long TV episodes are 40-55 minutes and a full-length play is 70 or more. This may seem like just a matter of amount of pages but the difference isn't how many pages you have in your script but what's in them.

Small Situation Vs. Big Situation

A TV show is about everyday events, nothing spectacular. There may be a problem they need to solve but it's nothing extraordinary. It's the same type of thing everybody goes through but it's unique in how these characters handle it. A full-length play is based on a single important event, something you rarely encounter in life and many people never have to deal with. Rather than being everyday banal things these situations are dire and require the utmost from these characters.

Needs Other Shows Vs. Stand-Alone

A single episode of a TV series will be entertaining but not the statement that the whole season is. The episodes need each other to make complete sense and convey the totality of the characters and world. A full-length play can be the only thing you see and still be completely satisfying. You may not get to know a character's personality like in a TV series, but you will know how they react in extraordinary circumstances and feel you know them just as war buddies feel a bond with each other though only acquaintances.

Repeatable vs. One Time Event

Episodic TV story events are told over again but with slightly different circumstances. If it was the gas bill they need to pay this week in a few weeks it could be about paying the cable bill. None of these situations is so special that it can't be repeated with a little alteration. A full-length play on the other hand is a once in a lifetime situation that will not be repeated without seeming tedious. You can't have a play about a King who wants to distribute his kingdom to his 3 daughters and then have one where one the daughters does the same with three of her sons. These events are finite and definitive and can't soon be replicated.

Personality Vs. Deep Character

Episodic TV shows are about getting to know characters' personalities. You want to see how they live their daily life and how they react to normal situations. They are never put to the test but rather seen in casual circumstances. A full-length play on the other hand is about the essential nature of a character. This type of work puts all the forces possible against this character so we can see what they are truly like. When faced with the harshest of circumstances how do they react? Only under pressure do we learn the meaning of fair weather friends.

Same Person Vs. Changed Person

The character at the beginning of any TV episode will be fairly similar at the end. At the end of the season there may be some changes but no single episode reveals too much about a character or makes them become a drastically different person. A full-length play is all about change. The arc of a full-length work demands that this person confront things they never have and will necessitate capacities they have never exercised before. A character in a full-length work will be confronted with things never seen before and will see a side of their personality they never knew existed. This will not be the same character that the work started out with.

Your idea for a play may end up being more like three TV episodes rather than a single compelling piece. Don't try to fit a story in the wrong medium. Don't limit yourself to a single way of telling a story. Instead of just filling a medium with what you want, take the time to learn its many facets so you can craft something that works best within it.