Does anyone know anything about 3 phase electricity?

[flyingjase]

I may need to upgrade to 3 phase electricity (I'm residential) due to a air source heat pump I want to get installed.

I phoned my electricity company (nPower) and the guy I spoke to didn't even know what 3 phase was, which is a bit of a worry.

Does anyone know if you can get it in a residential home?

How much it costs to install?

How long the lead time is?

What electricity company I would need to talk to to get some sensible answers?

Thanks

[hairyben]

flyingjase said:

I may need to upgrade to 3 phase electricity (I'm residential) due to a air source heat pump I want to get installed.

[b]I phoned my electricity company (nPower) and the guy I spoke to didn't even know what 3 phase was, which is a bit of a worry.
[/b]
Does anyone know if you can get it in a residential home?

How much it costs to install?

How long the lead time is?

What electricity company I would need to talk to to get some sensible answers?

Thanks

I know the leccy board are a joke these days, deal with them regularly, but Damn!

Is a single phase heat pump out of the question?

There'll be 3 phase in the street outside your door, you'll need to prep the site (varies, often install 4" duct from the mains position to the sidewalk boundary) and poss upgrades to your electrics depending what state they're in; price varies a lot but typically you'll be looking at a £1k or two for the prep and the leccy board will typically want a couple of £k.

You need to go through your provider initially, then through the network company, and they can advise on lead times. ANYTHING to do with elec co's is a nightmare and will involve countless calls going round in circles as you're passed back to departments you spoke to several calls ago, it will appear there is no-one there able or willing to undertake what you want but they do exist....

Speak to a spark and if you go ahead make sure the spark knows the score on this kind of work, the power company round here always try to cancel the works on the day claiming the sites not ready so they can charge you a nice fat £500 cancellation fee for "wasting their time" and leave you with no electric, you need someone who knows how they will try to do this and who'll basically babysit them on the day and argue them into motivating their fat arses into doing their job.

[silverthorn2151]

Wow, prepare yourself for more pain than you can possibly imagine!

Took us, i.e the client, me, the contractor and the sub-contrator 10 months to get supplies into some flats we were working on in Kilburn.

And loads and loads of quids and loads and loads of hoops to jump through.

I'm not sure I have EVER seen a 3 phase supply coming into a domestic property though and I suspect it will cause a heap of issues to deal with.

[sjj84]

Can you not get a single phase pump? Or what are the specs of the one you are looking at? You can get single to three phase convertors, they're quite expensive dependant on size, so you'd need to weigh up the costs, if you can even get one that's suitable. As said, anything to do with the electrical board is a nightmare and costs a fortune.

[flyingjase]

Ouch, this sounds like a nightmare and maybe looking at a single phase will avoid a lot of pain (and I can believe every word)

nPower called me back 10 mins ago and said, "yes we can do it sir, they are booked to install it on the 3rd of June and there is no charge"

I'll believe that when I see it, it can't be that easy!

[hairyben]

silverthorn2151 said:

I'm not sure I have EVER seen a 3 phase supply coming into a domestic property though and I suspect it will cause a heap of issues to deal with.

Yeah there's a good few places about with it- often big houses that have been converted in several flats then deconverted back to a house will have a 3 phase cut out left in (but only 1 phase in use), sometimes houses are just big enough and have enough fancy electrical carp they need it.

Had a crazy bint a few years ago who decided during the refurb that what her victorian 5 bedder really needed was electric underfloor matting... 20kW worth of it.

[hairyben]

flyingjase said:

Ouch, this sounds like a nightmare and maybe looking at a single phase will avoid a lot of pain (and I can believe every word)

nPower called me back 10 mins ago and said, "yes we can do it sir, they are booked to install it on the 3rd of June and there is no charge"

I'll believe that when I see it, it can't be that easy!

impossible, unless you already have 3 phase on site and just need a meter swap! Anything else would require a site survey just to begin with.

but yeah if you can spend more for an better inverter unit or whatever instead, do it.

[Robb F]

flyingjase said:

I phoned my electricity company (nPower) and the guy I spoke to didn't even know what 3 phase was, which is a bit of a worry.

You would have thought they at least employed people with a basic degree of electrical knowledge...

[55allgold]

Interesting - my house has 3-phase for some reason. Or at least I believe it does: there are four wires into the house. I'd always assumed this was something to do with the Economy 7 wiring that this place used to have.

Is there a good 'home' use for 3-phase? I know some industrial equipment uses it.

[DrDeAtH]

it will all turn to poo when/if EDF get involved. Couldnt organise a p*ss up in a brewery... USELESS!!!!!

[Ganglandboss]

Robb F said:

flyingjase said:

I phoned my electricity company (nPower) and the guy I spoke to didn't even know what 3 phase was, which is a bit of a worry.

You would have thought they at least employed people with a basic degree of electrical knowledge...

I once met a bloke who worked for the supply authority fitting meters that didn't know the difference!

It was the day of the 2002 World Cup Final and the landlord of a pub I'd been working on rang me up, kicking off because a load of his power had gone off, including the tellys! I rushed out and found yellow phase was down. He had only just taken the pub on and there were no seals in the service fuses (honest) so after confirming there was nothing from the meter, I found it only had an 80 amp fuse in what was supposed to be a 100 amp per phase supply. I swapped a couple of circuits to red and blue in the distribution board serving the bar so I could get the tellys back on. Cue rapturous applause and several offers of a pint. I told him he needed to get the energy supplier out but and he said that so and so in the bar worked for the leccy board and would sort it.

Two days later, I got a call. He was kicking off again because his air conditioning unit that I installed a supply to wasn't working. He was pissed off because he had been charged by the service engineer who said the problem was the power supply. I checked the supply:

Red - Neutral - 230V
Yellow - Neutral - 230V
Blue - Neutral - 230V

Red - Yellow - nothing but a bit of stray EMF
Red - Blue - 400V
Blue - Yellow - 400V

When I went to the cellar, it was obvious what the problem was. The supplier's cut-out had two fuse carriers on the red phase and one on the yellow and blue phases. The bloke from the electric board had just taken the tail out of the yellow phase and connected it onto the spare way on red phase. As the chillers were single phase and the only three phase load was this A/C condenser, everything else worked.

The landlord went upstairs and got the bloke who did it out of the bar. He had a coat on with the supply authority's logo and an ID badge behind a clear pocket on the front. When I told him the problem, he looked puzzled. He genuinely didn't know that there was actually a difference in potential between the different phases and he fitted meters for a living!

[caziques]

Who's been telling you that 3 phase is required for a heat pump?

Out of standard 2.5mm house wiring you can pull at least 5kW, which will give a heat pump something around 15kW output.

There are a few small heat pumps around that require 3 phase, but these are the exception rather than the rule.

If someone is trying to sell you a 3 phase unit when there is a single phase alternative I would go elsewhere.

[x type]

Ganglandboss said:

I once met a bloke who worked for the supply authority fitting meters that didn't know the difference!



I checked the supply:


Red - Yellow - nothing but a bit of stray EMF
Red - Blue - 400V
Blue - Yellow - 400V

commonly known as split or poly phase metering

used when 3 phase isn't available in the street ,

[Ganglandboss]

x type said:

commonly known as split or poly phase metering

used when 3 phase isn't available in the street ,

No, it was a TP&N supply until he b*ll*cksed it up.

[rex]

We have had a 3 phase supplyn installed. Needed a 4 inch duct but had no problems. Was installed by SSE with no problem. Chap that came out to assess the site came up with a good solution for not having overhead cables on the property (which most houses have in our area) and could not have been more helpful. Arrived on day stated for install, no hassles with install and Bobs your uncle. Cost about 3.5K as they dug up a fair bit of grass verge next to the pavement to hide the cable. This made the cost up to the 3.5K rather than the 2K quoted initially.

[bucksmanuk]

rex said:

We have had a 3 phase supplyn installed. Needed a 4 inch duct but had no problems. Was installed by SSE with no problem. Chap that came out to assess the site came up with a good solution for not having overhead cables on the property (which most houses have in our area) and could not have been more helpful. Arrived on day stated for install, no hassles with install and Bobs your uncle. Cost about 3.5K as they dug up a fair bit of grass verge next to the pavement to hide the cable. This made the cost up to the 3.5K rather than the 2K quoted initially.

£3.5k, that’s what I was quoted, but persevere OP, you have some barriers in front of you getting through to the right person at the electrical supplier. Once you have found them, it’s quite easy - I believe, I couldn't afford the £3.5K, but I know people who have had it done.
They send a real electrician round to do the job, who knows exactly what they are doing. None of that monkey with a code P certificate stuff.

[mrmr96]

I cant see any good reason why a regular household would need or benefit from a 3 phase supply - as none of your normal household applicances will make use of it.

[Brite spark]

mrmr96 said:

I cant see any good reason why a regular household would need or benefit from a 3 phase supply - as none of your normal household applicances will make use of it.

flyingjase said:

I may need to upgrade to 3 phase electricity (I'm residential) due to a air source heat pump I want to get installed.

hence op's requirent for a three phase supply

you should also realise this is ph so "regular" or average doesn't come into it, added to that is that some on here have interesting hobbies and workshops to play in where a 3 phase supply would have its advantages for machinery or motors, car ramps, compressors etc


ok I agree you are probably not going to put a kettle on three phase but some large cookers or heaters could be.

1. The most likely future demand for three phase electric supplies is for people who buy electric cars and want the ability to fast charge the car at home#

The last one is the stupidest reason I can think of though

Edited by Brite spark on Friday 20th May 00:25

[OzzyR1]

I'm a QS (I know, I know) and funnily enough we are doing this at the moment in a house down in Kensington.

Just got a quote from the contractor for bring a new 3-phase supply in for £3,850 incl builderwork, making good etc which seems in the right area.

[Mr GrimNasty]

mrmr96 said:

I cant see any good reason why a regular household would need or benefit from a 3 phase supply - as none of your normal household applicances will make use of it.

Apart from anything else, any equipment with a sizeable induction motor will be better off as 3 phase supply as it's cheaper to make them and they're more reliable.