Looking For Small Tankless Water Heater That Can Be Mounted In Enclosed Space

Updated 01/27/2026 | Published 01/09/2026

Question:

Hello, I have an adventure style trailer I can send a pic to help visualize. I am currently rebuilding it with built in water tanks and I am looking to hard mount an instant hot water heater. I am wondering if there are any options out there for hotwater heaters that are rather small and can be placed in an enclosed space. We are currently running a no name hot water heater brand from amazon but it needs to be hung up outside the trailer to work properly. Wondering what my options are. Thank you

asked by: Roger T

Expert Reply:

Hey Roger, thanks for reaching out. Based on what you described, the Excel RV Tankless Water Heater # EX93FR is a strong option to consider for your trailer rebuild. It’s much smaller than most tankless units at 11-1/4 inches wide, 14-5/8 inches tall, and 5-1/4 inches deep, making it well-suited for enclosed compartments or other tight mounting locations.

Unlike many portable heaters, this model is designed for hard mounting and does not need to be hung outside to operate properly. It’s vent-free, requires only minimal clearances (about 2 inches on the sides and 8 inches above), and runs on propane with D-cell batteries for ignition, so no 12V or shore power is required. That makes it a good fit for off-grid or custom trailer setups.

In terms of performance, it delivers up to 1.6 gallons per minute, which is ideal for tasks like washing dishes or taking quick showers. The main things to plan for are proper propane supply, water connections, and ensuring the mounting location meets clearance and ventilation guidelines.

Take a look at the picture I included. It shows a solid example of how this thing can be installed.

Feel free to email me pictures of your build. I'm definitely interested to take a look!

expert reply by: Jesse M

Excel RV Tankless Water Heater Example
(click to enlarge)

Jesse M.

1/27/2026

Hey Roger, how did the Excel tankless water heater work out for your trailer rebuild? It sounds like a great match for an enclosed setup. Sharing how it performed could help others planning similar off-grid builds.