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Where to hang a sauna thermometer

Updated: October 2026

The heater display says 90 °C and the wooden dial is still in the seventies. That gap is usually the room, not a broken needle. Where to hang a sauna thermometer decides which layer of air you are reading. A Finnish cabin is hotter near the ceiling than at the bench, and the controller sensor often sits above the stove so it can run the heater. The dial is there so you can see the air around your head. Listings and GBP prices are on the [sauna thermometer comparison](/hub/steam-baths/sauna-thermometer). We did not heat a cabin or move a sensor. A qualifying amazon.co.uk purchase can earn a commission at no extra cost to you.

The heater display says 90 °C and the wooden dial is still in the seventies. That gap is usually the room, not a broken needle. Where to hang a sauna thermometer decides which layer of air you are reading.

Our top picks

Ulsam Ulsam Round-01

Best overall

Ulsam Ulsam Round-01
7.8/10about £12.89
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TFA TFA 40.1055.50

Rank 2

TFA TFA 40.1055.50
8.2/10about £14.39
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Hojalis Hojalis dial and hourglass

Alternative

Hojalis Hojalis dial and hourglass
6.4/10about £16.99
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On this page
  1. 1.Why the two numbers disagree
  2. 2.Where to hang the dial
  3. 3.Hole, hook or screws
  4. 4.What you do not adjust

Why the two numbers disagree

The two numbers are doing different work. Harvia’s English MyHarvia note puts the heater sensor above the stove at the ceiling, where it can switch the stove, and a second sensor about 20 cm below the ceiling on the opposite wall reads the air around your head. A mechanical dial is closer to that second job. While the room is still heating, Harvia describes a gap of 10–20 °C as normal. That note is about Harvia’s own sensors, so it does not certify your wooden gauge. Auroom’s sheet illustrates a ceiling at 100 °C, an upper bench around 70 °C, and the floor around 40 °C, as leaflet figures, not a measurement of your cabin. Oceanic Saunas says never hang the gauge above the heater, or it chases the set point. HUUM treats a gap beyond about 10–15 °C as a placement check, not a reason to move the 230 V sensor.

Where to hang the dial

Hang the dial on the wall opposite the heater, about level with your head on the upper bench. Oceanic usually puts that spot about 30 cm below the ceiling, and Auroom’s sheet uses 20–30 cm below the ceiling. Fischer’s English sauna note repeats head height and says not to place the gauge directly above the heater. Some US pages put a point 1 m above the sitting bench. That is a different sentence, and in a tall cabin it can sit in cooler air than head height. Measure from the ceiling, then check you can read the face from the seat. Keep the gauge out of the door draught and the plume off the stones. A dial above the heater reads the set point rather than the bench. A steam cabin is a different climate, covered on the steam room thermometer page.
Ulsam Ulsam Round-01

Testsieger

Ulsam Ulsam Round-01
7.8/10about £12.89
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Hole, hook or screws

Look at what arrived before you drill. Several gauges in this set ship with a hole or a keyhole and no screws. TFA reviews mention a hanging hole. Ulsam is specified as freestanding, and a review mentions a keyhole. Hojalis lists two screws for the hourglass strip. A slot needs a single screw or a picture hook in sound timber. A strip that lists two screws needs both, or it swings. Do not drill the heater wall. The cable and the controller sensor are already there. Use a freestanding dial only when the leaflet says so and the shelf is at head height, not above the stones. A long screw through a thin lining can pierce the vapour barrier, so stop if you cannot find solid timber. Which scale you ordered sits on the sauna thermometer buying guide.

What you do not adjust

The dial is not the cut-out. It does not switch the heater or replace the sensor that limits the stones. Leave that sensor where the heater manual put it, almost always above the stove at the ceiling. Moving it so the numbers match is 230 V work. Call an electrician if the sensor or the supply has to move. A large gap after the room is hot is a placement check first. Once the cabin has levelled, the wall gauge should still read lower than a ceiling sensor, because bench air is cooler. A new needle that never moves is a return under the Consumer Rights Act 2015. Hanging it over the heater does not repair it. If you are still choosing, see best sauna thermometer.

Common questions

How high should a sauna thermometer hang?
Hang it at head height on the upper bench, about 20–30 cm below the ceiling. A figure of 1 m above the sitting bench is a different convention. Check you can read the face from the seat.
Why is the wall gauge lower than the controller?
The controller sensor usually sits above the heater so it can run the stove. A dial on the opposite wall reads cooler bench air. Harvia describes a 10–20 °C gap as normal while its room is heating.
Can I hang it above the heater so the numbers match?
The numbers will move closer, because the dial then sits in the same hot pocket as the controller sensor. You will be reading the set point, not the air around your head. Oceanic, Auroom, and Fischer all say not to hang the gauge directly above the heater.
Does a sauna thermometer need screws?
Not always. Several listings arrive with a hole or a keyhole and no screws. A slot needs one sound fixing, and a strip that lists two screws needs both.
Should the thermometer be on the heater wall or the opposite wall?
Put it on the opposite wall. The heater wall holds the controller sensor, the cable, and the hottest plume. The stove wall agrees with the set point more often and tells you less about the bench.
When should I call an electrician about the temperature gap?
Call an electrician when the heater sensor or the 230 V supply has to move, not when the wooden dial reads lower than the controller. If the sensor cable is damaged, that is electrical work and it sits outside hanging a gauge.

Related pages

Analogue or digital sauna thermometer

Sauna thermometer

Best sauna thermometer: 581 ratings or a low price

Sauna thermometer buying guide: scale, unit and power

Steam room thermometer: Finnish dial, wrong climate

Sources

Sources taken from the research digest. Listings were checked on 19 October 2026.

  1. Oceanic Saunas — combined thermometer and hygrometer (retrieved 19.10.2026)
  2. Auroom — thermo-hygrometer sheet (retrieved 19.10.2026)
  3. TFA Dostmann — analogue sauna thermo-hygrometer 40.1055 (retrieved 19.10.2026)
  4. TFA — English instruction column, climate bands (retrieved 19.10.2026)
  5. Wild Sauna UK — analogue versus digital (retrieved 19.10.2026)
  6. legislation.gov.uk — Consumer Rights Act 2015, section 9 (retrieved 19.10.2026)
  7. GOV.UK — product safety advice for businesses (retrieved 19.10.2026)
  8. Redbridge Council — saunas and steam rooms code of practice 3 (retrieved 19.10.2026)