Towel rail timer

[Russell griffiths]

Following on from another thread, what sort of timer can be used with an electric towel rail, the flex outlet is already in position but is permanently on so I would like the ability to run it for a few hours a day. 

Edited August 29, 2017 by Russell griffiths

[Nickfromwales]

Any timeclock tbh, as long as the 230v AC rating of the contacts is rated accordingly.

One like this is a neat all in one solution with fuse, isolator and timer in one. 

https://www.electricaldirect.co.uk/product/fused-timer-spur-white-875917?vat=1&shopping=true&mkwid=s_dt&pcrid=157072925424&pkw=&pmt=&gclid=EAIaIQobChMImvPe06j81QIViL3tCh1q5AusEAQYASABEgKxx_D_BwE

[Russell griffiths]

Could I use an immersion  timer. @Nickfromwales

Edited August 29, 2017 by Russell griffiths
Crap spelling as usual

[PeterW]

Yep you can use anything that can handle 16A resistive load ...

 

I have one time clock controlling all floors and towel rails - comes to 1450w all in so a little over 7A

 

 

[Russell griffiths]

ta very much. 

[Jeremy Harris]

I used immersion timers.  Cheap, fit a standard back box and easy to programme.  Ours is on the landing, so it outside any zone.

[Russell griffiths]

Thinking of our new build rather than this old crock we live in now, if you have the timer remotely situated how have you got the flex from the towel rail to it ?  Have you replaced the flex that they are supplied with. 

[Nickfromwales]

7 minutes ago, Russell griffiths said:

Thinking of our new build rather than this old crock we live in now, if you have the timer remotely situated how have you got the flex from the towel rail to it ?  Have you replaced the flex that they are supplied with. 

Have a break in the supplied cable, say 100mm into the stud wall and inline crimp it to the cable coming from your timer / controller. 

This one came with a cable transit at cost, but a piece of 15 or 22mm chrome pipe with a pipe collar would do it. 

[Jeremy Harris]

It's easy to replace the supplied cable, usually.  Neither of our towel rails came with a cable fitted, just terminals and a seal and cable clamp under the cable entry cover where the element is fitted.  If doing this, remember to use heat resistant flex, not standard PVC stuff that may go brittle and crack after a while.

[Gone West]

I used these for my electric towel rails.

 

http://www.timeguard.com/products/time/immersion-and-general-purpose-timeswitches/7-day-fused-spur-timeswitch

[Guest Alphonsox]

We used something similar from screwfix

 

http://www.screwfix.com/p/greenbrook-t205-scr-kingshield-7-day-fused-digital-timer-spur-switch-230v/7643g

[Russell griffiths]

Thanks everyone most helpful ?

[Crofter]

Quick question for the ill informed.

If I have E7, do I need to sync my towel rail's timer with the off peak time? Or does it run off two diffeent circuits?

[Jeremy Harris]

12 minutes ago, Crofter said:

Quick question for the ill informed.

If I have E7, do I need to sync my towel rail's timer with the off peak time? Or does it run off two diffeent circuits?

 

 

Everything in the house that's turned on during the E7 period will be charged at the E7 rate, there's only a single circuit.  There used to be two circuits for the older off-peak storage radiator type systems, where only the heating and hot water circuit was switched and charged at the off-peak rate, but I think that disappeared many years ago now.

 

So, if your towel rails are turned on during the E7 period, the energy they use will be charged at the E7 rate.  If they are turned on during the peak rate period the energy they use will be charged at the peak rate.  If you only want them on during the E7 period then you need to fit timers that make sure they only come on during that period.

[Crofter]

Thanks Jeremy, I get a bit confused because my current house uses a rather peculiar dual circuit system.

If I could drift the thread a little, I have yet to get my head around the wiring of the UVC- there are two immersions, and I gather that the lower one is designed to go on the E7 supply, with the top one used for boost. There must be multiple ways of skinning this particular cat, e.g. a simple switch for the boost (pref one that times out after an hour, so it can't be left on all the time), and a timer on the lower one set to sync with the E7 times- or is it better to get a fancy all in one box to control both? Perhaps a question for @Nickfromwales?

[Nickfromwales]

One of these

[Temp]

Nick may correct me but I thought that with a dual immersion the top one was the "normal" element and the lower one was the boost? The idea being that hot water rises so the tank heats from the top downwards. So normally only the top element is used and only the top part of the tank is heated. Then if you know demand will be higher you turn the bottom one on so it heats down to a lower point. 

[Nickfromwales]

20 minutes ago, Temp said:

Nick may correct me but I thought that with a dual immersion the top one was the "normal" element and the lower one was the boost? The idea being that hot water rises so the tank heats from the top downwards. So normally only the top element is used and only the top part of the tank is heated. Then if you know demand will be higher you turn the bottom one on so it heats down to a lower point. 

Normally I'd say yes, but as this is not a huge UVC in a nice rental I'd say stick with the lower for maxing the UVC out on e7 and just have the upper as boost ( eg you can put a sign saying "please press once before showering for continuous hot water" if it was deemed necessary of course. It ( the boost heater ) could even be triggered by flow to the shower via a flow switch and contactor, and a timer. 

Its just one of those things where there are a lot of eventualities that need to be considered. A boost switch is a simple backup / contingent.  

[Nickfromwales]

@Temp

In the 'old days' they had a switch marked Sink / Bath and that toggled between a high up immersion and another near the base. As @Crofter is renting this out he can't really set times for low / peak DHW demand, so it's got to be ready to rock pretty much 24/7 in occupancy.   

[Crofter]

47 minutes ago, Temp said:

Nick may correct me but I thought that with a dual immersion the top one was the "normal" element and the lower one was the boost? The idea being that hot water rises so the tank heats from the top downwards. So normally only the top element is used and only the top part of the tank is heated. Then if you know demand will be higher you turn the bottom one on so it heats down to a lower point. 

 

My gut feeling is that it would be the other way round. When you use boost it's because you're in a hurry, so you don't want to wait for the whole tank to heat up, hence you use a higher up element and just boost the top of the tank. Could be wrong, and often am...

[PeterW]

I'm going for one of these linked to the upper immersion. 

 

http://vi.raptor.ebaydesc.com/ws/eBayISAPI.dll?ViewItemDescV4&item=331040175427&category=57215&pm=1&ds=0&t=1497958701000&ver=0&cspheader=1

 

Lower is the E7 overnight one, and hopefully with 300 litres of water we will never need to use it ..!!

[Crofter]

1 hour ago, Nickfromwales said:

One of these

 

That's rated at 3kw... would I run just the e7 immersion off it, and have something else for boost?

[Crofter]

6 minutes ago, PeterW said:

I'm going for one of these linked to the upper immersion. 

 

http://vi.raptor.ebaydesc.com/ws/eBayISAPI.dll?ViewItemDescV4&item=331040175427&category=57215&pm=1&ds=0&t=1497958701000&ver=0&cspheader=1

 

Lower is the E7 overnight one, and hopefully with 300 litres of water we will never need to use it ..!!

 

That looks lovely and easy to use- perfect for my guests!

[Stones]

15 minutes ago, Crofter said:

 

My gut feeling is that it would be the other way round. When you use boost it's because you're in a hurry, so you don't want to wait for the whole tank to heat up, hence you use a higher up element and just boost the top of the tank. Could be wrong, and often am...

That's certainty the way the immersions were wired in the West Cost holiday let we used to use, and how our most recent rental was set up.

 

The holiday let only had a 150 litre cylinder which meant we needed to boost it every evening, for at least an hour.

[Jeremy Harris]

1 hour ago, Crofter said:

Thanks Jeremy, I get a bit confused because my current house uses a rather peculiar dual circuit system.

 

 

The dual circuit system used to be the standard system when off peak rates were first introduced a long time ago, but persisted for a fair time in some areas.  These usually have a time switch, separate off peak meter and separate switched circuit for all the off peak loads, often storage heaters and an immersion heater for hot water.

 

When Economy Seven was introduced, things were simplified, so there was sometimes just a single circuit with a dual rate meter, with an in-built time switch.  There could also be dual circuits with E7, but all electricity consumed on both circuits during the off-peak time is charged at the lower rate.  Things then got more complex again in some areas, when controlled off-peak systems were introduced, along with schemes like the E10 dual off-peak period schemes (only available in Scotland and North Wales, I think).  It very much depends where you live, as it seems Scotland has the widest variation of off-peak tariffs, AFAIK, whereas down here we get E7 or nothing, as far as off-peak tariffs are concerned (unless you're still on one of the legacy tariffs).

Edited September 18, 2017 by JSHarris