Immersion Timer

cruizer101

Looking for some help on immersion timer.

Currently the immersion runs of a switch in the kitchen (On/Off, Bath/Sink) no timer.

I'm looking to put in a timer but ideally replace the current switch with an all in one unit rather than adding a separate timer.
Want unit that will fit into existing back back ideally also, as the kitchen has recently been tiled so don't want to mess with, I really should have tried sorting this first.

Something like this https://www.fastlec.co.uk/ntt03-timeguard-ntt03-7-day-compact-electronic-immersion-heater-timeswitch.html
but I can't seem to see any which have bath/sink options (maybe they do but its just not clear), only really be using sink but don't want to completely lose bath functionality.

I think this one does both https://www.amazon.co.uk/Optimum-OP-ECOSAVE-Economy-Switch-White/dp/B076HFLXLW/ref=sr_1_1?s=diy&ie=UTF8&qid=1538388349&sr=1-1&keywords=immersion+timer+dual
but ideally want to just use the old back box so keep it standard switch size.
Also don't care about boost function.

The other option may be to put timer up beside immersion and leave switch as is but thats bit messy too.

Any advice or suggestions appreciated.

coylemj

I can't see how that unit on Amazon can do sink and bath, the description claims it can but the manual controls on the front have no selector so as far as I can see, it can't.

If your switch was in the hot press then the easiest solution would be to put a single channel timer between the mains feed and the existing switch. That way, you'd leave the On/Off switch permanently set to On and let the timer take care of power. You would still need to manually select sink or bath but you said that you are almost always on sink so that shouldn't be a problem.

Having the switch in the kitchen makes it awkward and what you will need to consider is getting a two channel timer but a lot of them are not standard size so they won't conveniently fit into your existing pattress (wall) box.

You mentioned putting a timer in the hot press, I don't think that will be possible because there is currently a four-core cable running from the switch to the immersion carrying earth, sink, bath and neutral. I don't believe there is any timer that can take more than one live input.

cruizer101

I think the way the unit I linked, and some others I've come across, works is the timer part uses the bath element and the boost uses the sink.
So they are meant for nightsaver dual rate (economy 7 and 10 in the uk I think) where you use the bath element over night to heat the whole tank on cheap rate and use the boost just during the day if need a bit of hot water in evening for a shower.

So yeah I think I need a full 2 channel timer which there aren't many of something like this would be ideal, except from data sheet I think it is not rated high enough
https://ie.rs-online.com/web/p/surface-mount-time-switches/1385665/
This one is rated to 16A so I think would do it but is bigger that I want although I think it mounts to single backbox, but also it is 200 quid which is more than I want to spend
https://ie.rs-online.com/web/p/surface-mount-time-switches/8179176/

In the hot press I had thought could a timer close one side of the circuit so say the neutral and leave the bath sink separate so the timer doesn't have to deal with them, but I'm not sure is that really possible or recommended (I wouldn't be trying anything like that without a proper electrician).

I do think the wiring for immersion switch might run from fuse box at front of house back through house potentially under where immersion is to the kitchen switch at back of house and then back to immersion so if wiring could be found it could maybe be cut off and all put in immersion and just stick blank on the one in kitchen.

I'm potentially looking at trying to zone the central heating to be able to heat just the hot water cylinder, it currently just heats everything, rads and cylinder. So if I can do that I'm not too worried about the immersion anyway for the hassle and cost it might be.

dodzy

coylemj wrote: »

I can't see how that unit on Amazon can do sink and bath, the description claims it can but the manual controls on the front have no selector so as far as I can see, it can't.

If your switch was in the hot press then the easiest solution would be to put a single channel timer between the mains feed and the existing switch. That way, you'd leave the On/Off switch permanently set to On and let the timer take care of power. You would still need to manually select sink or bath but you said that you are almost always on sink so that shouldn't be a problem.

Having the switch in the kitchen makes it awkward and what you will need to consider is getting a two channel timer but a lot of them are not standard size so they won't conveniently fit into your existing pattress (wall) box.

You mentioned putting a timer in the hot press, I don't think that will be possible because there is currently a four-core cable running from the switch to the immersion carrying earth, sink, bath and neutral. I don't believe there is any timer that can take more than one live input.

The main dial with the dip switches controls one channel and the small dial on the top right controls the other, albeit, not with the same degree of flexibility. It's really just a (push on/off) boost for 1/4 hr increments up to 2hrs MAX, but on the 2nd channel. It's pretty much a replica of the Grasslin QE7/7+ layout.

So, it's 2 channel operation, with no timer function on one channel.

coylemj

cruizer101 wrote: »

I think the way the unit I linked, and some others I've come across, works is the timer part uses the bath element and the boost uses the sink.
So they are meant for nightsaver dual rate (economy 7 and 10 in the uk I think) where you use the bath element over night to heat the whole tank on cheap rate and use the boost just during the day if need a bit of hot water in evening for a shower.

dodzy wrote: »

The main dial with the dip switches controls one channel and the small dial on the top right controls the other, albeit, not with the same degree of flexibility. It's really just a (push on/off) boost for 1/4 hr increments up to 2hrs MAX, but on the 2nd channel. It's pretty much a replica of the Grasslin QE7/7+ layout.

So, it's 2 channel operation, with no timer function on one channel.

+1 the UK specs. for a two-channel timer seems to assume that you run the Bath element at night on the reduced rate and in the daytime you can do a 'Boost' by using the Sink element. So you don't have unlimited flexibility to operate either element when you choose to.

Another example.... Sangamo have a two-channel timer but the user manual says the following, I have emboldened the relevant piece .....

This product differs from a simple time switch as it has programs built in that match with Economy 7, Economy 10 and Eco 20:20 electricity tariffs. This ensures your tank operates during off peak times avoiding expensive peak use. As such this controller is not freely programmable, you can minimise the program times within your off peak period but not go outwith it

https://www.sangamo.co.uk/collections/immersion-controllers/products/powersaver-dual-flexi?variant=8397116866615