Santon Premier water storage tank

[Wanttoleavesky]

I have gas boiler for central heating and hot water. We have a Santon Premier water tank in our en-suite which holds 150l.

We have the timer set for hot water to come on twice a day; once first thing for showers and then late afternoon for kids bath and maybe a shower. I didn't even think the hot water tank would use electricity but turns out it does (after googling electricity saving tips). So can we turn this off and still have the hot water required for morning shower, hand washing during day, one sink of hot water for dishes and bath for kids?

Whilst reviewing our electricity usage I realised we use over twice the national average for a standard 3-bed detached house and are using much more than neighbours with a similar house and way of living so I'm trying to work out ways of saving electricity and some money.

Does the hot water cylinder have an immersion heater or heaters? Have you perhaps got those set to come on as well as well as the hot water on the heating controls?

Not sure, will go and check as I'll need to look out the manuals. We only have one timing control box which is for hot water and heating which is in the utility near the boiler. We do have a switch labelled "water heater" near the cooker in the kitchen which is at the back of the house but the hot water cylinder is in the ensuite at the front.

the front panel mentions "immersion heater elements"

Have a look around the hot water cylinder for any kind of switch or timer. They are usually in the cupboard with it or nearby.

Theres no timer but there is a switch in the cupboard and in the kitchen. It also doesn't have a jacket and all the pipes are exposed so I'm thinking a trip to B&Q for some insulation this evening.

I'm confused though about conflicting info on the internet.

So having the immersion element in the hot water tank means that if the boiler breaks we'll still have hot water as we can heat it up using electricity unlike a combi boiler, I understand that. But surely if my gas boiler breaks I can simply turn back on the immersion switch and get hot water once its warmed up rather than keep it on all the time?

Not sure I understand what you are asking. Yes, if the boiler fails you can still have hot water using the immersion heater. Yes, once the water has heated up you turn the immersion heater off.

Electricity is about three times the cost of gas so it may be cheaper to switch the hot water on using the boiler controls for a while if you need to top up the hot water and the boiler is working.

if your cylinder is heated by the boiler, you should turn off the immersion heaters until the day the boiler breaks down.

what colour is the cylinder?

If it is a modern round white one, the heat losses are so low that it won't cost much to leave the boiler set to HW on all the time. It is slightly more economical to time it for on from half an hour before, to half an hour after, bath and shower times. That way it will be able to reheat for the next bath while you are splashing around in the first one. There will be plenty remaining for washing hands and dishes through the rest of the day. Cost of gas to heat a modern cylinder with a modern boiler may be as little as 50p a day, perhaps half that if you live alone.

We've got a conventional gas boiler which is on a timer to heat the water twice a day with the occasional boost if required. We've also got a hot water tank in a cupboard which I knew held the hot water as it does run out.

However what I'm learning today is that the hot water tank has a heating element inside of it which seems to be on all the time (hence our ridiculous electricity bills) and I'm wondering if I can turn off the heating element in the hot water tank and only turn it on again if the gas boiler breaks.

So I thought I was heating the water with gas, but maybe not. My gas bill is less than the average but electricity almost three times more than the national average so maybe this is why and I just need to turn off that switch!!

This is what we have.

At the moment the timer is set for less than an hour in the morning and about an hour around 4/5pm so I thought but if the switch in the top corner is turned on then I suppose it’s heating it’s self and not using the gas boiler.

Why do we have two switches though? One in the cupboard and one clearly labelled in the kitchen.

show us your switches and timer please

and all the pipes around the cylinder and boiler

Sorry I’ve not been back sooner. Pictures attached.

We turned off the water heater switch in the kitchen and still have hot water but it’s definelty cooler than before as in we can run a bath for the kids and not use much cold water.

The main reason for this discovery was our electricity bill was horrendous but it still looks like we’re going through 22kwh per day even with this turned off which is crazy. I was hoping that was the main culprit but i’ll need to do more investigation.

if your boiler is a fairly modern one, and the HW is turned On, it should be able to heat a bathfull of water in half an hour. If it is not as hot as you would wish, look at the temperature setting on your boiler. in winter it should probably be about 70C. The temperature on your cylinder has to be lower (because heat flows from the hotter to the colder thing) and typically about 60C. It was probably preset on installation and you are not expected to change it, it should be checked as part of the service routine, especially if you express any doubts on the temperature.

if you have a thermometer, test the temperature of the HW as it comes out of the hot tap.

I see you have two thick white flexible cables going into the top of the casing, these are probably for an upper and a lower immersion element. The cables probably feel a bit rubbery. Each of them will use 3kWh per hour costing about 50p all the time it is turned on until the water reaches its target temperature, and one of them would take about two and a half hours to heat the entire cylinder (so much slower and more expensive than the boiler) so see if you have two switches and if they are both turned off. If you stand at the electricity meter while an accomplice turns them on and off, you will probably notice a difference in the speed the meter spins or flashes, unless the water is already fully hot. There may be one or two hatches on the side or front of the cylinder (not visible in your photos) for access to the elements, you don't need to touch them.

It is very important that electric immersion heaters cut out before the water becomes scalding, your thermometer will detect that. Some very distressing accidents have occured when they overheat. They are adjustable, and fairly modern ones also have an overheat cutout.

Thanks. I’ll try turning them both off as we unfortunately don’t have a wee dial that goes round on our meter otherwise I’d be like my dad and siting watching it spin round!! It’s just a digital numerical meter.

Should I give all the pipes and tank a jumper?

Oh, and boiler is a Worcester and put in 5 years ago

the cylinder looks like a modern unvented one, so there will be an insulating layer already. You can see an external shell, the actual cylinder with the hot water is inside it, and the gap been cylinder and casing is packed with insulation.

It would be best to insulate all the pipes. They are probably 15mm and 22mm diameter. an old system may have 28mm.
The "bylaw" grade is thicker and better, but not essential unless the pipes are in an unheated area such as a loft, shed or cellar. I use it though, as long as there is enough room to to fit it. You can cut it with a serrated knife.

The white cables go into the sockets in the photo. Only one has a switch so I’ve turned that off now so hopefully that’ll make a change.

Hey, just a wee (probably not required or interesting) update.

We've had the hot water tank turned off and the water was not at all hot or enough for kids bath or a shower in the evening. We could just get a shower in the mornings but I was having to turn on the HWT at 4pm to get enough hot water for the evening.

So when we got our boiler serviced recently I asked the plumber and turns out that the zone valve for the hot water was broken. So when the timer was telling the hot water to come on the zone valve wasn't fully opening so it wasn't heating the water. However the reason we were getting some hot water in the morning was that I've still had the heating coming on first thing to take the edge off when the kids get up and the zone valve for the heating also works the hot water.

So its all sorted now and hopefully our electric bill will be greatly reduced.