What Size Xtreme Boat Engine Bay Heater Do I Need for a 24-Foot Sea Ray Stored on a Trailer?

Published 10/28/2026

Products Featured in This Question

Xtreme Heaters Boat Bilge Heater - 400 Watts - 15' Cord

$359.95

Xtreme Heaters Boat Bilge Heater - 600 Watts - 15' Cord

$419.00

Xtreme Heaters Boat Bilge Heater - 800 Watts - 15' Cord

$469.00

Question:

I have a 2008 Sea Ray 240 Sundancer with a MerCruiser inboard/outboard engine. I keep it on a trailer next to my house in Tennessee and we usually get a few nights below freezing each winter. Would the 400 watt Xtreme heater be enough or should I go with the 600? I'm trying to avoid having to winterize it every time we get a cold week.

asked by: Doug

Expert Reply:

Hey Doug!

For your 24' Sea Ray, I recommend the Xtreme Heaters 600W Boat Heater # XH368FR.

While the 400W model # XH298FR is generally recommended for boats up to 24', stepping up to the 600W model makes sense since your boat is stored on a trailer and loses heat faster than one sitting in the water if that makes sense.

We also have the 800W model # XH668FR for larger boats up to approximately 35', although that would likely be more heater than you need.

All three have built-in thermostats that automatically turn on around 40°F and shut off around 55°F.

Will your Sea Ray be stored outdoors with a cover, or inside an enclosed building?