sizing a sauna heater

Sizing a Sauna Heater

 

As a general rule of thumb a sauna heater needs 1 Kw to heat 50 cubic foot of room space.  This is a general rule and an outdoor sauna or a sauna built on outside walls may need to have the heater oversized.

As an example a 6'x7'x7' sauna room should require a 5 Kw heater.  (252 cubic feet divide by 50 = 5.04).

Because a sauna is heating air, you will find most sauna minimize the ceiling height.  A 6-7 ceiling is almost always standard.  Never build a sauna in an 8 foot room as a good portion of the heat will be at the ceiling where it is not used.

Electric Sauna heaters turn off once the desired room temperature is met.  This means that a larger heater simply works less than a smaller heater so there is virtually no energy savings by purchasing an under sized sauna heater.  If in doubt always go up a size.

 Heater Sizing Chart

SIZE (Watts)

VOLTS

PHASE

AMPS

FUSING

WIRE

MIN
(Cubic

MAX
Feet)

4000

240

1

16.7

30

10

100

150

5000

240

1

20.8

30

10

150

250

6000

240

1

25

40

8

200

300

6000

208

3

16.6

30

10

200

300

7500

240

1

31.3

40

8

290

375

7500

208

3

20.9

30

10

290

375

9000

240

1

37.5

50

8

360

450

9000

208

3

25

40

8

360

450

12000

240

1

50

60

6

450

650

12000

208

3

33.4

50

8

450

650

15000

240

1

62.5

80

4

600

800

15000

208

3

41.7

60

6

600

800

18000

208

3

50.3

60

6

800

1000

Standard residential voltage for North America is 240 volts, single (1) phase.