hot tub supply in domestic dwelling 32A, 100A supply

[ian w j]

Help Needed !!
The wife has just purchased a hot tub off eBay! I am a spark but not a bright one!! I was just looking into what's required for the supply and they are stating 8-10kw load 32-40amp supply. To an an isolator and have Rcd protection.. yeah ok so far. I know about the zones regarding position of isolator and other equipment as per the regs, but I am stressing about the demand and diversity of the installation. I'm going to do the work and get a friend to pass it off and certify.

Currently I have a 100amp single phase domestic supply.

The dis board has:
2 x 32a rings
1 x 32a radial cooker supply with single socket(cooker is 13a socket)
3 x 6a radial light
1 x 6a smoke
1 x 6a water(no immersion heater)

I've done a diversity calc not taking into account the smoke and the heating time clock and come up with 103amps using a 32 amp supply to the hot tub.
My supply is 100amps !! Is this right??

 

[normanton]

I think there has to be a certain element of common sense here. I mean unless you plan on running the jacuzzi, shower, cooker, every appliance in the house and have every light in the house switched on, I'd say you'll be fine :coolgleamA:

 

[UNG]

No offence but do you know all aspects of electrical wiring? The sparkys on site who I meet can only wire houses, when it comes to star /delta delta 690v and control circuits with relays and plc's, the don't have a Scooby do either! We all have different fields that we are good in and when I am not sure Is ask.:89:

Sounds like you are from the recently qualified part of the industry who believe it is split into domestic, commercial and industrial and you cannot have the knowledge or be qualified to work in all of them

I agree to an extent but regardless as to what field your in this is very basic stuff ???
Only you know what your house is pulling so only you can make a decision as to whether your hot tub will overload your supply???
Say for instance your correct and your main fuse is 100 amp, do you seriously think you will pull over 100 amps at any one point????
If you are that worried why dont you switch on everything in your house and clamp it to see what your pulling !!!

And how many DNO fuses or any fuses rupture at their exact rating

I think what has been forgotten is that your hot tub will only likely ever pull 32A when first heating up. It'll just be ticking over keeping temperature, etc. for the rest of the time. If you are that worried about it turn everything else off when you first power it up!

A mate of mine has a hot tub that at the time of installation was advised it needed a 30A supply I've had a clamp on it a few times and with all the pumps (2 water, 1 air ) and heater running it draws no more than 25 Amps in normal use it is drawing about 17 Amps (heater and 1 pump). The air pump is very rarely used as it tends to cool the water very quickly and not getting many hot days in this country you want to keep all the heat you can in the water

welcome to the forum dude,check out Manchester Evening News 22nd July,Tuesday this week,Title;VERY HOT TUB...

Having read that and looked at the pictures I wonder whether that is a result of some one discarding a cigarette over the fence as they walked past. If the control equipment in the tub caught fire I would have thought it would have melted the pipes and the tub and released the water onto the fire. A mate of mine has had a few problems with his hot tub which is nearly 10 years old but this has always tripped the MCB or the RCD when a fault has occurred so it is possible the Manchester fire could have been caused by a bad installation

 

[Engineer54]

Looks like you're all talking to yourselves again, the OP hasn't been seen here for 2 days!! lol!!

 

[telectrix]

perhaps he drowned.

 

[ian w j]

This site has really helped! I now know where all the sad electricians hang out! Goodbye

 

[PEG]

...Just cut out the second article in the Evening News,regarding another hot-tub fire. I am folding them,and inserting them in the instruction book my good mate gave me,prior to his pending install. I feel they lend weight to my future quote...:bow: ...and to the OP, "sad,electricians ?" ...never bin' accused of being either...

 

[Colfly]

now look fella pull yourself together, if you look at what you have posted again you will see you have the same as everybody else in your street except some of them have 10kw showers as well, come on man get a grip.

It is normally a 80A fuse inside. With your board up to full load tong test your incomer. For your hot tub run a 6mm T+E from your 32A mcb this will future proof your circuit. Just think there are thousands of these things are sold for peoples homes and not a problem as you are not running your board at full load on each circuit ever.

 

[DPG]

It is normally a 80A fuse inside. With your board up to full load tong test your incomer. For your hot tub run a 6mm T+E from your 32A mcb this will future proof your circuit. Just think there are thousands of these things are sold for peoples homes and not a problem as you are not running your board at full load on each circuit ever.

Worth checking the thread date. This one is 8 years old.

 

[7029 dave]

Worth checking the thread date. This one is 8 years old.

Some old names in this post, memories.

 

[DPG]

I love post 55. Good old Eng54 eh!

 

[7029 dave]

I love post 55. Good old Eng54 eh!

Yeah miss Eng54 RIP, he loved these !!!! lol

 

[Gavin John Hyde]

If worried get a priority unit so the hot tub and cooker cant both be on. Alternatively one of those matte units with whole house monitoring. Get the 60a one, route hot tub through it and if use in house goes too high the device cuts supply to hot tub. Designed for evs but can be used for other things

 

[littlespark]

I think the OP gave up on this thread well before the rest of them.
I’m just imagining a huge hot tub, sitting in the garden, full of cold water. The wife fuming because someone couldn’t take friendly advice.

Pulling 60 amps with what he was saying?
No chance.