Wood-Fired or Gas-Heated?
Which Hot Tub System Is Right for You?
Wood-Fired or Gas-Heated?
Which Hot Tub System Is Right for You?
AquaRelax hot tubs can be equipped with either a wood-burning stove or a gas heating system — both designed for efficient outdoor use.
In this article, we’ll explore the key differences between the two: how long it takes to heat the water, which is more energy-efficient, and which system suits your home or holiday property best.
Wood-Fired Heater
Fast water heating (on average in 2–2.5 hours)
No need for gas or electricity connection
Suitable for any property, including off-grid homes
Creates a special ambiance: scent of wood, crackling fire
No need for gas or electricity connection
Suitable for any property, including off-grid homes
Creates a special ambiance: scent of wood, crackling fire
Gas Outdoor Heater
Fast water heating up to 24 kW without wood or constant monitoring
Runs on propane gas cylinder with automatic shut-off in case of overheating or water flow stop
Efficient consumption — up to 4 kg of gas for 1200 L
Runs on propane gas cylinder with automatic shut-off in case of overheating or water flow stop
Efficient consumption — up to 4 kg of gas for 1200 L
GAS WATER HEATER 20–24 kW
High-performance gas water heater designed, for example, for hot tubs and spas.
The heater has high power output for fast and safe water heating. Flow rate — 10 L/min, the temperature difference between the inlet and outlet is 25 °C. This means a temperature increase of approximately 15 °C per hour for 1000 liters of water.
Nominal power: 20 kW (30 mbar, 1.5 kg/h)
With a 30 mbar regulator and 2 kg/h consumption, the power output is 24 kW.
Gas consumption: 1.5 – 1.6 kg/h
Heating time for a 1200-liter tub (from 6 to 37 °C): 2.5 hours
Gas usage: 4 kg
Fuel: Liquefied propane gas (LPG), operating pressure 30 mbar.
Suitable for heating water in hot tubs, spas, showers, dishwashing, etc.
Heater dimensions:
Height: 740 mm
Width: 345 mm
Depth: 160 mm
The heater has automatic ignition, activated by a minimum water flow of 7 L/min. The HGUNION19 pump included is specifically designed for this purpose.
If the water flow stops, the gas is automatically shut off. The same happens if the outlet water temperature exceeds 75 °C or the flame goes out.
The heater features a digital temperature display for inlet water.
An optional protective box is available to shield the heater from wind and rain. The front panel of the box can be removed during use. The case is made of heat-resistant material on the back and sides, with a slanted thermal shield on top to direct the heat outward.
The heater has high power output for fast and safe water heating. Flow rate — 10 L/min, the temperature difference between the inlet and outlet is 25 °C. This means a temperature increase of approximately 15 °C per hour for 1000 liters of water.
Nominal power: 20 kW (30 mbar, 1.5 kg/h)
With a 30 mbar regulator and 2 kg/h consumption, the power output is 24 kW.
Gas consumption: 1.5 – 1.6 kg/h
Heating time for a 1200-liter tub (from 6 to 37 °C): 2.5 hours
Gas usage: 4 kg
Fuel: Liquefied propane gas (LPG), operating pressure 30 mbar.
Suitable for heating water in hot tubs, spas, showers, dishwashing, etc.
Heater dimensions:
Height: 740 mm
Width: 345 mm
Depth: 160 mm
The heater has automatic ignition, activated by a minimum water flow of 7 L/min. The HGUNION19 pump included is specifically designed for this purpose.
If the water flow stops, the gas is automatically shut off. The same happens if the outlet water temperature exceeds 75 °C or the flame goes out.
The heater features a digital temperature display for inlet water.
An optional protective box is available to shield the heater from wind and rain. The front panel of the box can be removed during use. The case is made of heat-resistant material on the back and sides, with a slanted thermal shield on top to direct the heat outward.
In the photo — the AquaRelax wood-fired heater for a hot tub, installed in the technical compartment.
AquaRelax Heating Systems — The Heart of Every Hot Tub
We use high-performance heaters, specifically engineered to deliver fast and even heat distribution. Depending on your space and preferences, you can choose:
Our heaters can be installed outside or integrated into a dedicated technical compartment.
Since we manufacture them in-house, we guarantee the highest quality in every detail.
We use high-performance heaters, specifically engineered to deliver fast and even heat distribution. Depending on your space and preferences, you can choose:
- Wood-burning heater — completely off-grid and atmospheric, perfect for remote properties or nature-focused settings.
- Gas heater — compact, automated, and convenient; ensures fast heating with zero effort.
Our heaters can be installed outside or integrated into a dedicated technical compartment.
Since we manufacture them in-house, we guarantee the highest quality in every detail.
© 2025 AquaRelax
