Add to favorites
Boat Engine Compartment Heater Built-in Thermostat, 800W Boat Cabin Heater with Safe PTC Element and Waterproof Fan HMA800 Multi-Use Boat Bilge Heater to Prevent Your Cabin Pump from Freezing, White by Therelmax - Used condition

Boat Engine Compartment Heater Built-in Thermostat, 800W Boat Cabin Heater with Safe PTC Element and Waterproof Fan HMA800 Multi-Use Boat Bilge Heater to Prevent Your Cabin Pump from Freezing, White

Brand: Therelmax

Condition: Used
$14353
$36398
-61% Save $22045
Updated: 3 days ago

Description

【Extend Your Boating Season】You won't have to worry about freezing damage with the THERELMAX boat engine heater. The boat engine compartment heater keeps the bilges warm and dry, whether you patrol the waters or just like taking your boat out on colder days, you'll always be good to go with an engine compartment heater on board. THERELMAX marine engine block heater will also help you to significantly reduce your winterizing costs.

【Built-in Adjustable Thermostat】Equipped with an adjustable thermostat that return control to the user, allowing for more applications. Perfect for a boat bilges, RV bays, wellhouses, greenhouses, workshops, lithium warmers, service van, recreational vehicles, and more! (Temperature range: 41℉-86℉. For boat engine compartment heating applications, it is recommended to set the temperature to 46℉.)

【3s Fast Heating】This Marine Heater with 800W safe PTC ceramic heating technology rapidly heats the bilge compartment. This prevents critical engine and compartment components from ever getting close to freezing temperatures.

【Built for Ultimate Reliability】This boat heater features a rust-resistant aluminum alloy case, a sealed electronics module, and a waterproof fan to provide consistent temperatures throughout the engine compartment. We live and breather harsh marine environments, so we designed each component with reliability in mind.

【Trusted Quality】The housing and core components are made of powder-coated epoxy aluminum alloy and aluminum to prevent rust, extend the life of the heater. We are confident in the quality and construction of each products and ensure that all of our products are produced and certified to regional, national, and international industry standards. THERELMAX offer a 1-year warranty to cover manufacturing defects.

THERELMAX offers a cost effective, energy efficient solution that improves battery performance and increases the resale value of your boat. You won't have to worry about freezing damage with our signature boat engine heater. The boat engine compartment heater keeps the bilges warm and dry, so you'll have a boat that still works like new. A THERELMAX marine engine block heater will also help you to significantly reduce your winterizing costs. When the batteries are protected, you can rest assured that your boat is ready to go. Whether you patrol the waters or just like taking your boat out on colder days, you’ll always be good to go with an engine compartment heater on board.

Sold by

Amazon Warehouse

Verified Retailer

Official Amazon outlet for open-box & returned items

  • Backed by Amazon's A-to-Z Guarantee
  • 30-day return policy
  • Ships from Amazon fulfillment centers
  • Price verified on Amazon

Product Details

SKU:
awhd-us-b0dbt3h37n
Model:
HMA800-W
Country:
US
ASIN:
B0DBT3H37N

Shopping Smarter

Common questions about buying open-box and refurbished.

Why buy refurbished or open-box?
Refurbished and open-box products offer the same performance as new at a fraction of the price. You're already saving $220 on this listing. They've been inspected, tested, and are ready to use — the only difference is the price tag. Buying refurbished also reduces electronic waste, extending product life cycles and keeping functional devices out of landfills.
What's the difference between open-box and refurbished?
Open-box products are customer returns that have been inspected and confirmed functional. They may show little to no use — often the item was returned simply because the buyer changed their mind. Refurbished products have been professionally repaired or restored by technicians, tested to meet or exceed manufacturer specifications, and sometimes come with a warranty. Both are a smart alternative to buying new.
Why use OpenBoxFox?
Finding refurbished deals is time-consuming — you'd have to check Amazon Warehouse, Reebelo, Dyson Outlet, and others separately for Therelmax products. OpenBoxFox aggregates these listings in one place, so you can compare and find the best deal without the legwork. We update pricing daily so you always see current availability and real savings.
Is it safe to buy refurbished?
Yes. Products listed on OpenBoxFox come from established retailers like Amazon, Reebelo, and Dyson — not unknown third-party sellers. Each retailer has buyer protection policies, return windows, and in some cases warranties. You get the price advantage of used goods with the purchase security of a known retailer.

Sign in to save items

Save favorites and get alerts when prices drop.

or

We'll email you a link to sign in instantly — no password needed.