Sauna in outhouse

[musicspark]

I have been asked to fit a sauna in an outhouse. It is a TT supply and the building is only 1 meter from the house.

In addition there is to be a 16 A radial for a few workshop tools and a 6A Lighting circuit

I was intending to fit an earthed Metal 4 way CU and have looked at special locations (section703 in the BRB) but any tips, suggestions, or helpful info would be welcome.

 

[Andy™]

i would go with an insulated IP rated CU instead of metallic

 

[musicspark]

[quote name='Andy

 

[musicspark]

Incidentally, how many Amps will yer average sauna draw?

 

[Andy™]

whats your average sauna?

id guess 3KW, but they may have larger heaters

 

[musicspark]

[quote name='Andy

 

[Lurch]

I've just done one that was 3ish kW for the heater, plus a couple of lights. The controller was rated for 4.5kW IIRC.

The CU I would use insulated if it was just a building for the use of the sauna and nothing else, if the CU is in the workshop then whatever you like I suppose.

 

[Andy™]

depends on situation - if its likely to get damage, then metallic may be an advantage.

 

[PC Electrics]

One of the voices in my head is telling me that if the earthing is TT then regs require an insulated CU. Haven't got my books to hand, so maybe someone else could try and find it in the OSG?

Edit: it's on page 24 and applies to the main CU only wrt the tails not being RCD protected. As yours is a sub board and the supply to it will be RCD protected a metal enclosure is okay.

 

[Lurch]

One of the voices in my head is telling me that if the earthing is TT then regs require an insulated CU.

In general, then yes, unless you can ensure the live end of the tails will not come into contact with the enclosure, and this only applies to the main tails from the meter to the first RCD.

 

[PC Electrics]

Ta Lurch, you added yours as I was editing mine.

 

[musicspark]

I've never connected one before, are there considerations for the cable regarding heat.

how should i approach this?

 

[musicspark]

Ta Lurch, you added yours as I was editing mine.

Glad to see you guys are on the ball

 

[PC Electrics]

There's a section for saunas in the BRB. Have a look. I'm sure you need 105C cable for the heater.

 

[Lurch]

I've never connected one before, are there considerations for the cable regarding heat.

Only if it's likely to get hot!

Basically, a sauna is like an immersion heater at the bottom of an old tin bin. Wire it in whatever you want, twin to the controller, heat res flex to the heater is the usual way.

 

[musicspark]

Only if it's likely to get hot!Basically, a sauna is like an immersion heater at the bottom of an old tin bin. Wire it in whatever you want, twin to the controller, heat res flex to the heater is the usual way.

I was thinking of 1.5 butyl or hofr; which would be best?

 

[Lurch]

I was thinking of 1.5 butyl or hofr; which would be best?

Yes!

Either\or, personal choice really. Check the instructions first, it may give some recommendations and guidance.

 

[PC Electrics]

Well, well. You learn something every day.

17th edition, 703.52 requires the wiring to the heater to be heat resisting, but does not give a guide temperature.

Whereas 16th edition, 603-07-01 required 180C thermosetting (rubber) insulated cord to the heater.

So I'd say put in the best you can reasonably get hold of - at least 85C flex such as would be used on an immersion.

 

[Andy™]

One of the voices in my head is telling me that if the earthing is TT then regs require an insulated CU.

but only for non-RCD protected wiring - so you could have an RCD in plastic enclosure, and then tails into metal DB

 

[musicspark]

[quote name='Andy