Shower Pump Timed Switch?

Mango Joe

Hi All,

We've too many teenagers and they like to have the longest showers & no about of pleading, reasoning or discussions on flooding the septic tank, heating bills, leaving the bathroom drenched with condensation (ceiling mould a problem now too despite ventilation being reasonable) or using up all the hot water before others can avail of it sink in with them for very long.

I'm talking about 40-50 minute showers at least...its ridiculous.

I'd like to put in a 10 minute timer on the pump to discourage this bad habit. On testing when the power to the shower pump is cut there is enough pressure to finish a shower, for example rinse out shampoo etc, but I'm hoping that the reduced pressure might cause them to finish up and get out.

I searched online a few times and other people have discussed it but I never found a solution I liked that didn't have some major downside.

The concerns I have are:

1. Potentially damaging my Grundfos 3 Bar Pump (Brilliant unit, so quiet, going 10 years plus now, recommended via Boards.ie!)

2. Killing some or all of the children by setting it up so they're reaching for an electrical switch with wet hands to resume their interrupted shower. Was thinking it would have to be IP66 touch panel/sealed or something.

Anyway....Surely there's a reasonable, tried and trusted approach, I'd love to hear your thoughts.

Thanks.

John.G

You might measure the flowrate from the shower at normal showering temperature but at its maximum flowrate, it may be giving power shower rates of flow ie > 10 LPM, you could then fit a restrictor to reduce that flowrate to say 4 to 6 LPM so that 40 minute shower uses "only" 50% of the hot water and leaves enough for a few more showers.

corkgsxr

We use a time delay switch for our heating. Old system.

One click gives 30 mins. 2 1 hour. 3 2 hours.

Surely theres a select your time versions.

Wouldn't matter to the pump

Sleeper12

Mango Joe wrote:

I'm talking about 40-50 minute showers at least...its ridiculous.

At a modest 10 lpm you are talking about 400 to 500 litres of water. At 15 lpm you are talking about 600 & 750 litres of water. You must be mistaken about the amount of time they are in the shower itself or else they are having cold showers. You couldn't have hot water cylinder big enough to store all of this water.

Why not install an electric shower. A energy rated. They only put out 3 to 4.5 litres of warm water per minute.

John.G

Interesting alright, what may be happening is that after the cylinder store is used up is that they are reducing the flow rate to match the cylinder coil rating, a 10 kw coil will give a continuous flowrate of 4.8 LPM (from cold water at 10C) much the same as the electric shower and will give a higher or lower flowrate depending on that rating. With all that showering going on I would be inclined to match the flowrate (via a restrictor) to the cylinder coil rating except that it is only rated at 5 kw or so. The electric shower is regulated to 9kw but at much higher energy costs which will be substantially more than gas/oil with that kind of apparent usage.

antix80

It may be that you're just a control freak and the bathroom is the only refuge they have from you.

Set up your own electric shower so you don't have to worry about running out of hot water. Leave your kids to it and stop catastrophizing. They'll be long gone before damp becomes a problem. You haven't even measured their water usage.

Wearb

antix80 wrote: »

It may be that you're just a control freak and the bathroom is the only refuge they have from you.

Set up your own electric shower so you don't have to worry about running out of hot water. Leave your kids to it and stop catastrophizing. They'll be long gone before damp becomes a problem. You haven't even measured their water usage.

MOD NOTE: You need to be more civil if you want to keep posting here.

Mango Joe

John.G wrote: »

You might measure the flowrate from the shower at normal showering temperature but at its maximum flowrate, it may be giving power shower rates of flow ie > 10 LPM, you could then fit a restrictor to reduce that flowrate to say 4 to 6 LPM so that 40 minute shower uses "only" 50% of the hot water and leaves enough for a few more showers.

Thanks for this advice - I don't want to affect the quality of the showers, I just want to encourage normal length showers! Its a very nice setup once its being used reasonably!!

corkgsxr wrote: »

We use a time delay switch for our heating. Old system.

One click gives 30 mins. 2 1 hour. 3 2 hours.

Surely there's a select your time versions.

Wouldn't matter to the pump

Thanks for your suggestion - I've a Horstmann switch like this on my immersion heater and think its brilliant....I did think of it but any of the ones I found looked like cheaply made and borderline fire hazards and the reputable brand ones run for too long, ie 1-2 hrs isn't practical!

Sleeper12 wrote: »

At a modest 10 lpm you are talking about 400 to 500 litres of water. At 15 lpm you are talking about 600 & 750 litres of water. You must be mistaken about the amount of time they are in the shower itself or else they are having cold showers. You couldn't have hot water cylinder big enough to store all of this water.

Why not install an electric shower. A energy rated. They only put out 3 to 4.5 litres of warm water per minute.

It's a 300 litre cylinder kept at ~70 degrees celsius, once the thermo mixer shower valve sorts that out theres how much water at 40-45 degrees? I would think its well in excess of 400L anyhow.....We've solar heating and I now find the hot water having to be topped up by burning oil....In June/July/August.

Thanks for your suggestion, much appreciated and entirely valid.... but the whole point of getting the shower pump was to get away from the miserable electric shower experience...I once read on here that "they're very convenient but you may have to run around a bit to get wet."

John.G wrote: »

Interesting alright, what may be happening is that after the cylinder store is used up is that they are reducing the flow rate to match the cylinder coil rating, a 10 kw coil will give a continuous flowrate of 4.8 LPM (from cold water at 10C) much the same as the electric shower and will give a higher or lower flowrate depending on that rating. With all that showering going on I would be inclined to match the flowrate (via a restrictor) to the cylinder coil rating except that it is only rated at 5 kw or so. The electric shower is regulated to 9kw but at much higher energy costs which will be substantially more than gas/oil with that kind of apparent usage.

Thanks for this - I'm not sure I fully understand what you're saying - Getting tripped up by the KW & LPM relationship here? ELI5 maybe!!!?!?

<MOD SNIP> NO BACKSEAT MODDING PLEASE

John.G

300 litres at 70C will give a mixed 545 litres @43C from cold at 10C and that's assuming that the HW cylinder is not getting additional heating during this period, if the shower is flowing 12 LPM then that stored supply will last a total of 45 minutes, this will require 21 kwh of energy and if you are happy with this then you can set the HW timer for a period long enough to heat the cylinder each morning to 70C but you are still left with the problem of "making" this last all day. Now because you have I presume a solar coil installed as well then its quite likely that only 150 litres are being heated in the winter by the boiler so you can adjust the above numbers accordingly.

As you suggested above you could install a timer on the pump something like the one above with a max boost setting of 10 mins which needs the boost button pressed each time a 10min shower is required, it is quite safe and may encourage less usage?.

antix80

Mango Joe wrote: »

Keep fighting the power kid, and tidy your room!!!!

Surprised you haven't wired up cctv to find out who's peeing the seat.

Mango Joe

John.G wrote: »

300 litres at 70C will give a mixed 545 litres @43C from cold at 10C and that's assuming that the HW cylinder is not getting additional heating during this period, if the shower is flowing 12 LPM then that stored supply will last a total of 45 minutes, this will require 21 kwh of energy and if you are happy with this then you can set the HW timer for a period long enough to heat the cylinder each morning to 70C but you are still left with the problem of "making" this last all day. Now because you have I presume a solar coil installed as well then its quite likely that only 150 litres are being heated in the winter by the boiler so you can adjust the above numbers accordingly.

As you suggested above you could install a timer on the pump something like the one above with a max boost setting of 10 mins which needs the boost button pressed each time a 10min shower is required, it is quite safe and may encourage less usage?.

Thanks for this John..... Yes this is what I was thinking, IP rated and 10 mins max. Also hoping to run wiring down existing conduit and mount it under existing lightswitch in hall so nobody has to go reaching into the hotpress.

When I'd started the thread I really was just looking for a discussion on ideas, assurances it wouldn't break the pump and hoping for a recommendation on a specific switch to order based on people having been happy with the one they'd installed or whatever.

corkgsxr

That's exactly the switch I have for heating. Handy cos I never used to turn it off. at night after

John.G

Ensure that it is installed correctly, a relay may have to be installed with the timer as the pump is probably ~ 400/450 watts.

Irish Steve

Been a while since I fitted one, there are timer relays available from the larger electrical wholesalers that can be programmed for on and off periods, so feasible to set up so that when the shower starts, it will detect that action, then run for (say) 10 or 15 minutes, but when it then stops, it won't restart for 10 minutes, which would avoid the problem of someone diving out to reset it with a quick power off. They're not massively expensive, and can be adjusted to set the periods with a wide range of times.

Mango Joe

Irish Steve wrote: »

Been a while since I fitted one, there are timer relays available from the larger electrical wholesalers that can be programmed for on and off periods, so feasible to set up so that when the shower starts, it will detect that action, then run for (say) 10 or 15 minutes, but when it then stops, it won't restart for 10 minutes, which would avoid the problem of someone diving out to reset it with a quick power off. They're not massively expensive, and can be adjusted to set the periods with a wide range of times.

Thanks for this Steve - We're getting very close to the end here I think

I'd always known the the best solution here involved a time delay period so that people wouldn't just keep hitting the reset button like a snoozed alarm on a Monday morning!!!

Could someone please link me to a specific product I can order, I did look but I'm not sure I'll pick the best option and I find that if your ring the counter in these shops they expect you to know the exact product you need.

Mango Joe

Can I bump this please? Still having the same issues and costs have risen dramatically since I first posted this.

I'd love to fit something like Steve haa suggested? Or whatever best solution might be.

I'm sure there's loads of people having this same issue?

Any help appreciated.

meercat

https://areliametershop.com/product/shower-timer-acqua-tempus/

youtheman

I prefer a more 'manual' method of 'controlling' the time my kids (now adults) stay in the shower. I have valves on the hot and cold supply from the pump in the hotpress. I slowly begin to close one (doesn't matter) then I switch to rapidly opening and closing. Random operation always has the desired effect, they give up on the shower. My system proved infallible as I never admitted to it, and they never asked !