40A Flow Switch

[LED Lighting]

Hi everyone

I am looking for a water flow sensor/switch to turn on a 11.5Kw shower.

The flow sensor/switch must be capable of handling 40A for a period of upto 2 hours of use.

Does anyone know of such a thing if one exists?

 

[LED Lighting]

What wrong with an old fashioned hot water tank with an immersion heater?

No room to place it in the flat!
already thought about this one but not an option

 

[KAS1]

Can they not use the "Public Baths" sorry just thought I was back in the 19340/50s or go to the local swimming pool a couple of times a week

I should of explained in the op.

the issue is this property is using a 5L (under sink) hot water tank to fill a bath, sinks, shower (non electric). The current tenants won't use the shower!

they have asked me to find away of filling the bath with hot water, I have looked at demand hot water heaters but can't find anything suitable.
I think the 2hrs was an over guess but could happen as tenant has been known to leave hot water tap on for hours.

has anyone else got any other ideas?

 

[LED Lighting]

The current tenant has learning difficulties (didn't want to go down this route) and refuses to use the hot water mixer shower!

this is the same reason way they sometimes leave the hot water running!
most if the time the carer runs the bath.

 

[Marvo]

I be very careful for liability purposes if you alter an appliance in order to make it operate in a way that it was not specifically designed and supplied to do so you will end up in court if something goes wrong.

In answer to your question I've never seen a 40A flow switch. We regularly use Johnson controls flow switches but the largest AC3 current capability is 16A as far as I know. Chances are if you do find a 40A flow switch it's going to be pretty large so I'd also suggest using a small flow switch together with a contactor.

 

[Richard Burns]

Can you not have an instantaneous hot water system and install a cut off timer so that it can only run for x minutes before it stops, I.e. enough time to run a bath. These can go up to about 8kw which shoudl have enough capacity if they have an attached tank.
If it is stopped and switched back on the timer resets, then if there is a problem the tenant is doing it deliberately.

 

[brighter_spark]

why couldnt you use an immersion heater?? surely thats got to be more cost effective. installation wise and power consumption wise?
also why a flow switch, ive never heard of one before how do they work.

thanks

 

[LED Lighting]

The idea is to install the shower in the water cupboard to supply hot water to the house, as you have to be able to turn the shower on and off - which people could forget to do I was thinking about using a flow switch (when there's water flow it closes the switch - allowing current to flow, no water flow - switch open)
either have the 40a supply attached to the flow switch or use a relay in between to lake the load from the switch just to turn the shower on and off, keeping bills down and stop it over heating.

 

[Tridentsystems]

Bad idea all round.

 

[LED Lighting]

Bad idea all round.

Thanks for your comment but please alaberate or offer a better option.

 

[babylonsBurning]

Some showers (maybe most, not sure) state that the hose (outlet) must always be open (not connected to tap, etc).

 

[HandySparks]

The idea is to install the shower in the water cupboard to supply hot water to the house...

This is a really bad idea. The instructions for every electric shower I've seen say do not restrict the output flow. They usually have a blow-out valve which ruptures on excessive output pressure and releases the pressure.

What about something from this page:
Redring Powerstream Instantaneous Water Heaters from Fastlec.co.uk

I suspect that you might have to get a plumber in who's registered to fit unvented water heaters.