Choosing the right sauna heater for your home, gym, log cabin or leisure centre can be a fun and easy process, but sometimes the cheapest sauna heater might not be the most appropriate heater for your sauna. Here are a few questions that anyone looking to buy a sauna heater should ask before choosing which one is best for their circumstances.

How do I know that the sauna heater is powerful enough to heat my sauna room?

This is the first question a sauna buyer should ask. If a heater is purchased purely on price or aesthetics, the buyer may find that the heater may struggle to achieve the desired temperature within a reasonable amount of time. In some cases where a low output heater is fitted into a large sauna, the room may never achieve a good temperature.
Avoiding this pitfall is thankfully very easy if you know about it in advance, we have sizing charts to help you on our website and we publish the technical specifications for every heater, showing what size range each product falls within. Now you just need to calculate the cubic volume of your sauna room.

Calculating the cubic volume of your sauna is easier than it sounds. Simply multiply the width, depth and height of the sauna room together, this will give you the volume of air inside the sauna. There is no need to deduct the space underneath the benches. If you have a glass wall or window, or your sauna is outdoors we recommend calling our sauna specialists on 01484 937 337 and we will be happy to adjust the calculation for you to account for the extra heat requirements.

What is the difference between a single-phase and a three-phase heater?

Generally, domestic properties are single phase and larger commercial buildings have three-phase power which allows for much greater electrical capacity. At Aqualine sometimes we speak to clients who have built a very large new sauna room in a domestic property, when they come to choose their heater, they sometimes either can’t find one powerful enough or order a commercial three-phase heater by mistake.
This pitfall is also easy to avoid if you think about sizing your heater early enough in the design process.
Every heater is labelled as either single (230V) or three-phase (400V) compatible on our website, our sauna specialists can also provide further advise and assistance in selecting a heater that will be compatible with your buildings electrical supply.

How important are heater exclusion zones?

The short answer to this is very important! Each sauna heater is designed with an exclusion zone around it which varies from model to model. This is to stop the heater causing damage to the sauna benches, walls and ceiling.
Sometimes, when ordering a sauna heater for a room with limited depth, low ceilings or a general lack of availablr floor space, this can lead to heaters being installed too close to combustible materials.
A tell-tale sign of this will manifest itself over time as any timbers that are too close to the sauna heater start to darken and eventually go black. This is quite common in saunas with a low ceiling height where a tall heater has been installed.
If in any doubt, speak to our sauna specialists, we can go through your designs with you, check that they are optimal and safe, and provide options on which heaters will fit best. There are always innovative solutions such as integrating the heater into the bench using heat proof flanges, mounting the heater behind a false wall, or by installing decorative stone walls behind wall mounted heaters to protect the timber.

Does my sauna heater require ventilation?

Yes! Sauna heaters all need to be ventilated, ideally with an air intake preferably at low level near the heater, and an air outlet at high level, preferably on the ceiling or wall opposite the air intake.
Ideally your sauna should be able to turn over fresh air six times per hour, it can achieve this with two appropriately positioned and sized vents with no need for any mechanical assistance. Some sauna designs instead have gaps under the walls or door offering a simplified solution.

Why do some sauna heaters look similar but have different prices?

Some saunas heaters come in lots of different variations. The Harvia Delta range for example has a simple version featuring easy to use built in controls, a less basic version with a simple digital controller, another version with a choice of high-end controllers sold separately, and also a ‘Combi’ version which features a built in steamer and high tech control panel which can adjust both the temperature and humidity.
Don’t assume that the cheapest is always the best, for example the Combi heater provides much more control over the sauna, so for the extra initial outlay it offers a more customisable sauna experience which you can adjust to suit your mood or personal preference. Speak to our team of sauna specialists for advice on which option is best for you.

Why are stones not included and why do some heaters require such a large amount of stones?

Stones are not included in the cost because most customers are simply replacing an existing aged heater and wish to use the stones they already have.
Some high-end Harvia heaters use a massive amount of exposed stones to allow the bather to apply more humidity, it also has the added effect of allowing the heat to spread more evenly in the room and linger for longer in between heating cycles.

What other gadgets and accessories should I be considering for my sauna heater?

This really depends on what kind of bathers you are anticipating. If you are buying a sauna heater for your home, you might consider a traditional bucket and ladle with sauna essences to invoke the scent of the Finnish pine forests. If you are buying for a commercial gym or leisure centre, your primary concern will probably be the health and safety of your services users, so you may wish to recess the heater safely behind a false wall and install a Harvia Autodose system to allow bathers to add water and essence to the sauna at the press of a button, without getting anywhere near a hot surface.

Speak to our team to see if these ideas can be incorporated into your sauna room. Contact us via the Live Chat on or call us on 01484 937 337.