What kind of Electric Shower install is possible with my existing consumer unit?

[fearny26]

Hi I am moving into a ground floor flat and would like to have a new electric shower installed above an existing bath tub, unfortunately due to low pressure from the hot water tank a plumber has advised a mixer shower is not an option and neither is a pump. I am rather new to all this sort of thing so apologies if anything I explain does not make sense.

The install itself seems pretty straightforward. Shower on the wall above the tub, isolator pull cord from the ceiling and then approx 10-15m cabling and trunking to the consumer unit which is in an enclosure on the wall of my bedroom.

Here's where I am unsure of the best way to proceed. The flat is setup for economy 7 tariff and as such the meter tails are split in a henley block and feed two Wylex fuse boxes, one rated to 100a and one to 60a. Both fuse boxes are also connected to an RCD rated 80a and 30ma tripping current. Both fuseboxes have a spare way each. The service fuse states 100a. The flat is all electric and has a cooker, an immersion heater, one storage heater.

As a side note once the shower has been installed it will make the boiler redundant and will likely never be used. I'm unsure if that will affect the shower install but just thought I'd mention. This will also mean the only appliance that can take advantage of the economy 7 tariff I'm currently on is the one storage heater and so I would be interested in changing the setup to support a normal tariff but I am unsure of the work needed to do that and any advice is appreciated. Finally I am renting this flat with one other person and its most likely it will just be for 1 or 2 years so while we would like to spend money on the shower and are happy to spend a little bit more if it means getting a more powerful shower. We would not be interested in any major work such as changing to a new CU as the cost will more than likely outweigh the benefit to ourselves in the short term and we are also living on a budget.

So I would like to know if its possible to wire up a shower straight into my existing setup and if so whats the highest strength of shower it can support?

Is it possible to wire up a separate shower consumer unit and would this allow for a higher rated shower?

If I wanted to change my tariff from economy 7 is it a big job or straightforward?

I have had one spark round so far but he seemed rather put off by my fusebox and I got the feeling he didn't want to know. He quoted £400 and said he could install an 8.5kw shower but anything higher and he said he would need to replace the entire CU and would be in excess of £1000.

Thanks so much
Jake

 

[telectrix]

a 8.5 kW shower wolud not be a problem connecting to that CU, maybe even a 9.5kW. altogh that CU is not ideal, there is a 30mA RCD protecting the installation, so it would be do-able without a great cost.

 

[Gary Gemmell]

Hi I am moving into a ground floor flat and would like to have a new electric shower installed above an existing bath tub, unfortunately due to low pressure from the hot water tank a plumber has advised a mixer shower is not an option and neither is a pump. I am rather new to all this sort of thing so apologies if anything I explain does not make sense.

The install itself seems pretty straightforward. Shower on the wall above the tub, isolator pull cord from the ceiling and then approx 10-15m cabling and trunking to the consumer unit which is in an enclosure on the wall of my bedroom.

Here's where I am unsure of the best way to proceed. The flat is setup for economy 7 tariff and as such the meter tails are split in a henley block and feed two Wylex fuse boxes, one rated to 100a and one to 60a. Both fuse boxes are also connected to an RCD rated 80a and 30ma tripping current. Both fuseboxes have a spare way each. The service fuse states 100a. The flat is all electric and has a cooker, an immersion heater, one storage heater.

As a side note once the shower has been installed it will make the boiler redundant and will likely never be used. I'm unsure if that will affect the shower install but just thought I'd mention. This will also mean the only appliance that can take advantage of the economy 7 tariff I'm currently on is the one storage heater and so I would be interested in changing the setup to support a normal tariff but I am unsure of the work needed to do that and any advice is appreciated. Finally I am renting this flat with one other person and its most likely it will just be for 1 or 2 years so while we would like to spend money on the shower and are happy to spend a little bit more if it means getting a more powerful shower. We would not be interested in any major work such as changing to a new CU as the cost will more than likely outweigh the benefit to ourselves in the short term and we are also living on a budget.

So I would like to know if its possible to wire up a shower straight into my existing setup and if so whats the highest strength of shower it can support?

Is it possible to wire up a separate shower consumer unit and would this allow for a higher rated shower?

If I wanted to change my tariff from economy 7 is it a big job or straightforward?

I have had one spark round so far but he seemed rather put off by my fusebox and I got the feeling he didn't want to know. He quoted £400 and said he could install an 8.5kw shower but anything higher and he said he would need to replace the entire CU and would be in excess of £1000.

Thanks so much
Jake

Forgive me if i am wrong but your E7 meter should supply all your leccie at night on rate 2 including the lights, ring main, shower, water heater etc!

Why would your boiler be of no use - dont you use hot water in the taps in bathroom and kitchen?

I am having my comfortplus white meter Horstmann replaced with an E7 for just this reason!

 

[ferg]

It really depends on how low your water pressure is.

If it's too low then some modern electric showers will stop heating when on a higher temperature setting.

 

[davesparks]

Hi I am moving into a ground floor flat and would like to have a new electric shower installed above an existing bath tub, unfortunately due to low pressure from the hot water tank a plumber has advised a mixer shower is not an option and neither is a pump. I am rather new to all this sort of thing so apologies if anything I explain does not make sense.

Considering that the whole point of a pump is to fix low pressure I would say the plumber is talking nonsense.
Talk to a couple of other reputable plumbers to get other opinions.
Personally I would avoid having an electric shower if at all possible, they are a poor, ugly, expensive substitute for a proper shower.
[automerge]1576431381[/automerge]
It might be worth looking at this new product @Dan has posted about

Shower Power Booster - Had a drop in water pressure?

https://www.plumbersforums.net/threads/shower-power-booster-giveaway-competition-ends-31st-december.111068/ There's a deal on these, but even when there isn't a deal going they can be a godsend. These little gizmos fire up the pressure of the water feeding your shower (or other taps)...

www.electriciansforums.net

Source URL: Shower Power Booster - Had a drop in water pressure? - https://www.electriciansforums.net/threads/shower-power-booster-had-a-drop-in-water-pressure.181422/#post-1594947

 

[Gary Gemmell]

Considering that the whole point of a pump is to fix low pressure I would say the plumber is talking nonsense.
Talk to a couple of other reputable plumbers to get other opinions.
Personally I would avoid having an electric shower if at all possible, they are a poor, ugly, expensive substitute for a proper shower.

Why not plumb it into the mains supply thats what i did with ours!
Only problem will be getting to the pipes if its under a tiled floor - nightmare then!

Much better pressure but still not as good as my local gym sadly!
Nice to have a power shower but each electrical item you add like a pump is just another point of failure and expensive layout in terms or reapirs and extra leccie!

 

[fearny26]

Sorry there is some confusion guys I will clear this up.

The water pressure for the cold mains is brilliant and it is this that I will use for the electric shower. The hot water pressure is poor due to the boiler/tank being at the same height as the shower and only a few meters away from the bathroom and this is the reason the plumber recommended an electric shower. I was not there when he said why he could not use a pump on the hot water tank feed but I believe it is due to the boiler being ground floor and the lack of space to install.

As for not using the boiler once the shower is in place its because its a large cupboard size tank and it would not be economical to heat the entire tank to just use a small amount of hot water for washing up each day. There are only 2 of us living here and we would not be taking baths.

I believe it would make sense to change from economy 7 as it would really only be the one storage heater on during off peak hours once the shower is in place as the boiler would probably never be used and theres not anything else I would be doing during those hours.

Thanks for you replies already
[automerge]1576432897[/automerge]

a 8.5 kW shower wolud not be a problem connecting to that CU, maybe even a 9.5kW. altogh that CU is not ideal, there is a 30mA RCD protecting the installation, so it would be do-able without a great cost.

Would you just use the spare way on the fuseboard to do this and are you able to give a ball park figure for the work?

Thanks
Jake

 

[Gary Gemmell]

Sorry there is some confusion guys I will clear this up.

The water pressure for the cold mains is brilliant and it is this that I will use for the electric shower. The hot water pressure is poor due to the boiler/tank being at the same height as the shower and only a few meters away from the bathroom and this is the reason the plumber recommended an electric shower. I was not there when he said why he could not use a pump on the hot water tank feed but I believe it is due to the boiler being ground floor and the lack of space to install.

As for not using the boiler once the shower is in place its because its a large cupboard size tank and it would not be economical to heat the entire tank to just use a small amount of hot water for washing up each day. There are only 2 of us living here and we would not be taking baths.

I believe it would make sense to change from economy 7 as it would really only be the one storage heater on during off peak hours once the shower is in place as the boiler would probably never be used and theres not anything else I would be doing during those hours.

Thanks for you replies already
[automerge]1576432897[/automerge]



Would you just use the spare way on the fuseboard to do this and are you able to give a ball park figure for the work?

Thanks
Jake

I think i see what you mean it just came across as you were using the hot water feed into the electric shower which is a bit mad as it should be a cold feed!

I presume you have a combi boiler I keep relating it to my setup which is a vented cylinder type boiler which i prefer to a combi anyway as like you I never use hot water except for having a bath so can dig where you are coming from viz a viz saving the cash on heating the water - it is a bit much just to do the dishes and splunge yer face for having a shave lol.

I wired my boiler up using a sonoff 15 amp smart switch which means i can switch it on when i am on the bus on the way home so its piping hot when i get in and i can see all the stats on power used cost etc on the inteface to the sonoff so you might consider that if you want to save cash - you can also set it on a timing basis to go on and off at set times but to be able to do it from your smartphone is just the dogs!

 

[Vortigern]

I would get a price on a new combi boiler to run your shower off of and a price for fitting an electric shower you might find it is far more economical in the long run to run off a combi and modernise your flat and get rid of the boiler tank and get more storage room. Just a thought.

 

[fearny26]

I would get a price on a new combi boiler to run your shower off of and a price for fitting an electric shower you might find it is far more economical in the long run to run off a combi and modernise your flat and get rid of the boiler tank and get more storage room. Just a thought.

Yes certainly in the future a small water heater would be ideal.

To Gary, it's actually an electric immersion heater on the water tank so yeah like you said a bit much just for a small amount of hot water use outside of showers. I'm not in a position to change anything big time right now so I'm happy to just heat up the kettle for washing up etc. Right now I'm purely focused on getting the shower in at a reasonable cost but all nice ideas for the future.