Can Dometic 310 Toilet be Replaced with a 320

Updated 09/29/2025 | Published 04/27/2025

Question:

I currently have a model 310 Dometic toilet in my RV. I want to replace with a model 320. Will the 320 fit in the same space i.e. didtance from flange to back wall, etc. Also is the water input to toilet the same - on the same side, same height from floor? My supply comes up through floor snd has an angle on it to go into toilet fill valve. I want to make sure I don’t have to modify water supply line

asked by: Glenn

Expert Reply:

Hey Glenn, there is a 1 inch difference for the "rough in" dimension between the two toilets you mentioned. The 310 has this dimension at 10 inches whereas the 320 part # DOM27FR has this dimension at 11 inches.

So if you have at least 11 inches between the center of the mounting flange to the wall you'd have the needed clearance.

If that checks then it would be an easy swap as everything else is a direct match and wouldn't require any modification.

expert reply by: Jameson C

Jameson C.

9/26/2025

Hey Glenn, did you find that you had the necessary clearance for the Dometic 320 in your RV? I'm curious to know if the swap was as easy as expected, as it could help others considering a similar upgrade.

Glenn H.

9/26/2025

@JamesonC- yes it was easy and I Had the clearance. However, you need to nake sure you have the clearance on your rv. For my rv, it did mive the toilet closer to the back wall, but it fit!