Thermomate 10L Outdoor Water Heater - Portable 2.64 GPM Tankless

In this review of the Thermomate 10L Outdoor Water Heater the bottom line is simple: it is a compact, propane-powered tankless unit best suited for RV owners and campers who need instant hot water without a large footprint. The single biggest reason to consider it is the high power output-up to 68,000 BTU/hr-with an advertised 2.64 GPM flow so hot water is available on demand when water supply and gas are adequate. The review evaluates setup, safety features, low-pressure startup and real-world use from the perspective of outdoor and mobile water heating.

Key Features

• Instant hot water: Maximum output up to 68,000 BTU/hr delivers fast heating so users rarely wait for hot water when supply and gas are sufficient.
• Steady flow rate: Rated at 2.64 GPM to support showering and basic camp chores without the need to preheat a tank.
• Low pressure startup: 0.7 PSI minimum startup with two magnetic water flow sensors lets the unit operate in low water pressure conditions common in some campsites.
• Multiple safety protections: Built-in overheating and flameout protection automatically shuts off gas at high temperatures or if the flame goes out, reducing safety risks.
• Anti-freeze drainage: A drain plug allows you to empty residual water for winter maintenance to prevent freeze damage in cold conditions.
• Portable design: Compact dimensions and light weight make it easy to store and carry for road trips and short-term installations.

Who It's For

The Thermomate 10L suits RV owners, campers and outdoor enthusiasts who need a portable, propane-powered tankless heater that is easy to install and does not require preheating. It is especially useful where compact storage and a higher BTU output are priorities, and for users who may face low incoming water pressure since it can start at 0.7 PSI.

Those who should look elsewhere include households that need steady whole-home hot water or installations where water pressure is unreliable below the stated minimum. Also, if durable commercial-grade components or premium shower fittings are required, some users have reported mixed build quality and accessory fragility.

Pros & Cons

Pros

• High heating capacity provides rapid temperature rise for on-demand hot water.
• Low pressure startup and dual flow sensors improve reliability at weak water supply points.
• Compact, lightweight design is convenient for RVs and camping storage.
• Safety features like overheating, flameout protection and drainable anti-freeze design add peace of mind.

Cons

• Some customers report inconsistent heating performance and occasional accessory failures such as the shower head.
• Build quality impressions vary; a few users found components less robust than expected for heavy daily use.

Specifications

Brand	thermomate
Power output	Up to 68,000 BTU/hr
Rated flow	2.64 GPM
Low pressure startup	0.7 PSI with 2 magnetic sensors
Safety features	Overheating and flameout protection, anti-freeze drain
Package contents	Gas water heater, gas regulator, shower head & hose, user manual, fitting kit
Size & weight	21.7in L x 7.1in H x 13.0in W, 17.9 lbs

Our Verdict

The Thermomate 10L Outdoor Water Heater is a practical choice for campers and RV users who need high BTU output and reliable low-pressure startup in a compact package. It offers valuable safety features and winter drainage for seasonal use, making it good value for mobile applications, though buyers seeking long-term heavy use or premium fittings may want a more robust alternative.

Frequently Asked Questions

Can this unit be used at high elevation?
Yes, but ensure water pressure does not drop below 0.7 PSI and confirm propane supply and regulator performance at altitude.

What hose fittings are required for a garden hose?
You need a female 3/4in GHT connector and a male 3/4in GHT connector to match standard garden hoses.

How do you winterize the heater?
Open the drain plug on the bottom right by turning counterclockwise and disconnect water lines to fully drain the unit.