Immersion timer

monseiur

Not sure if this is a plumbing or electrical query - elderly relative living alone wants to replace an APT timer on immersion to something more user friendly like perhaps a digital time clock. She basically needs to be able to pre set immersion to switch on twice or three times daily. Checked on line and have narrowed it down to two : EPH 1 Channel Digital Timeclock R17 and Hortsmann (Secure) Economy 7 Quartz Timer. I am not familiar with either. Which one should she go for ? Any recommendations for other good quality makes/brands would be greatly appreciated. Must be simple/easy to operate and reliable. Budget up to €100 approx

Thanks.

Sleeper12

https://switchcraft.ie/pss-powersaver-select-electronic-timer.html

This is a great one. Has a boost function as well as digital timer

monseiur

https://www.boards.ie/discussion/comment/121415039#Comment_121415039

Thanks Sleeper12 - that one seems more user friendly than the ones I selected and is reasonably priced.

Sleeper12

I've had that one in my own home for around 15 years. It's a little old fashioned now because it's not smart but still a great timer.

TheSunIsShining

Is there a smart controller that has the bath and sink option available does anyone know?

blackvalley

Slightly off topic but is there any clear evidence that putting your immersion on a timer is actually any cheaper to run than leaving it on constantly.

Read an article recently suggesting that using a timer to heat up the immersion from almost cold to normal temps is inefficient.

Have my own on a timer and works well but it’s an interesting theory

Wearb

https://www.boards.ie/discussion/comment/121417963#Comment_121417963

Heating the amount of water that you need at the temperature needed as close as possible to the time needed, is the most economical.

It's easier to understand if you understand that heat loss is proportional to the difference between the temperature of heated object (water in this case) and the temperature of the surroundings. The hotter the water The greater the difference in temperatures and therefore the greater the heat loss.

blackvalley

Would be very interesting to put a meter on the immersion and monitor electrical usage for a month with immersion permanently on and a month timed. As Wearb has said timed is more efficient but it would be interesting to see the actual difference

kirk.

https://www.boards.ie/discussion/comment/121417818#Comment_121417818

Probably but you can't simply replace a standard immersion switch with a smart switch .

It wont comply with wiring rules on its own without an isolator present

TheSunIsShining

Tks. What about basic timers? Is there one that can be used that covers the bath/sink option?

ptogher14

I recently did this over a number of months. Over the years I have always left the immersion on 24/7 over the summer months. This summer I trialled several different ways and measured to see what the cheapest. It was marginally cheaper to only put the immersion on for a couple of days rather than leave on 24/7. I'll pull out the exact figures later. For reference, I have a modern well insulated tank. Obviously also a lot of variables from household to household.

cnocbui

https://www.boards.ie/discussion/comment/121417963#Comment_121417963

The timer would be more economical. Look up Newton's Law of Cooling, which states something like that the rate of heat loss is proportional to the difference in temperature. If you had a cylinder with spectacularly good insulation that would change it a bit, but leaving it on constantly would bankrupt someone of meagre means.

I once had 3 phase power with a 3 phase instant hot water heater which heated mains water at 7bar of pressure and high flow rate to hotter than you could stand. No storage tank or heat loss. It was probably the most efficient way to provide HW you can have.

riddles

https://www.boards.ie/discussion/comment/121419362#Comment_121419362

Any idea what it costs to use immersion to heat water for a year - I remember seeing something like 200€ a year before electricity prices increased.

windowcills

Immersion on all day in the summer is a disgrace

Put on the immersion for 10mins and take a 3min lukewarm shower

Watch out for legionairs disease as it very dangerous to people on the internet

DublinDilbert

Nothing wrong with the screwfix one:- https://www.screwfix.ie/p/lap-digital-immersion-timer/1804r

It has a boost button on the top right.

10-10-20

I love the analogy of the kettle as a somewhat exaggerated example of that discussion on whether you should heat water continuously or only on demand.

ptogher14

Currently we use approx 125kwhr a month on the immersion which equats to approx 54euro a month. The hot cylinder is a factory insulated tank, as most modern day ones are. For reference there are only two people living in the house.

The difference between timing the immersion and leaving it permanently on was marginally. Permanently on worked out 1.95 a day vs timed for an hr in the morning and evening worked out at 1.70 a day.

Wearb

https://www.boards.ie/discussion/comment/121423224#Comment_121423224

That's 13% more expensive when "permanently" on.

I put permanently in parenthesis because the immersion would be controlled by its thermostat. Also the heat loss would be directly related to the immersion set temperature.

coylemj

On the topic of whether you can have a timer which can handle sink and bath, you can but, in this part of the world, it is always an Economy 7 model which only allows you to heat the bath element during off-peak (as defined by Economy 7) periods. I have never been able to find a two-channel immersion timer which give you full control over both circuits.

I have this Timeguard timer for several years now, it allows you to set a schedule for several on/off cycles per day or to do a one or two hour boost, all controlled from anywhere by a mobile phone or tablet. Since I bought mine, I see that they have added support for Google Home and Amazon Alexa.

It needs to be installed upstream from the Sink/Bath switch as it's a single channel timer i.e. you will still need to manually switch betwen sink and bath.

https://www.timeguard.com/products/wi-fi/wi-fi-switches/fstwifitu-wi-fi-controlled-fused-spur-tuya-edition/