Setting up your boiler?

Giblets

I was just looking at some advice on setting up my hot water system. I have a gas boiler (that also feeds to the central heating) and tank with immersion heater.
I've just realised my immersion heater is on permanently, so reading up have switched that off (as apparently costs 3-4 times gas), or is it worth keeping on at a lower temperature?.
So that just means I should adjust the boiler on/ off settings, so possibly early morning for showers and early evening for the kids bath?
Any advise, especially with the immersion heater.

Talldave

You should treat your immersion heater as being for emergencies only when the gas boiler has failed. I would replace the switch with a timer control switch that gives a 30/60/90 min type boost, which will ensure that it can never be accidentally left on, but will openly admit that that's a bit extravagant, especially if you had to pay an electrician to do the job.

As for timings, it really depends on usage.  We have our system configured for a couple of hours in the morning ending just before the first person gets up and then a longer period in the evening that covers dinners/bathtimes/bedtimes.  But we have a 300 litre tank - if yours is smaller an hour in the morning might be OK.  Experiment and see?

macman

Turn your immersion off and keep it for emergency use only.

matelodave

As others have said, turn off the immersion heater - it's costing you 4-5 times more than gas.

If the boiler has a temperature control, set it to around midway or 60-65 degrees. It the tank has a stat then set it to 60 degrees. Set the programmer or whatever controls your hot water timing to come on for about 2 hours approx 1.5 hours before you get up and see if there's enough hot water for your morning ablutions and to last you until about teatime. Then put it on again for another hour or so to see if you've got enough hot water for washing up and bath time through to the next morning. If you run out then put it on for a bit longer (say another half an hour)

There's no advantage it keeping the tank boiling hot all night when you are asleep , or during the day if you are out for most of it. Leaving the hot water turned on all day will just keep reheating and wasting heat through the pipework- juggle with the timer to optimise the on/off times and duration.

You can also minimise your use of hot water by making sure you dont let it run down the sink when washing or rinsing stuff - use cod where possible. Every time you run the hot tap you waste a lot of hot water just sitting in the pipework to get cold until you run it again.

Take shorter showers, shallower baths and perhaps fewer of them. Showers can use a lot more water than a bath if they have a high flow rate and you spend a long time in there - consider fitting an eco shower head or flow restrictor.

We get away with heating our tank for about an hour and half in the mornings just before we get up and that gives us enough hot water for a couple of showers and hot water right through to the next morning (it will even last two days but the second shower on the second day is  a bit lukewarm).

Ectophile

matelodave said:

As others have said, turn off the immersion heater - it's costing you 4-5 times more than gas.

If the boiler has a temperature control, set it to around midway or 60-65 degrees. It the tank has a stat then set it to 60 degrees. Set the programmer or whatever controls your hot water timing to come on for about 2 hours approx 1.5 hours before you get up and see if there's enough hot water for your morning ablutions and to last you until about teatime. Then put it on again for another hour or so to see if you've got enough hot water for washing up and bath time through to the next morning. If you run out then put it on for a bit longer (say another half an hour)

There's no advantage it keeping the tank boiling hot all night when you are asleep , or during the day if you are out for most of it. Leaving the hot water turned on all day will just keep reheating and wasting heat through the pipework- juggle with the timer to optimise the on/off times and duration.

You can also minimise your use of hot water by making sure you dont let it run down the sink when washing or rinsing stuff - use cod where possible. Every time you run the hot tap you waste a lot of hot water just sitting in the pipework to get cold until you run it again.

Take shorter showers, shallower baths and perhaps fewer of them. Showers can use a lot more water than a bath if they have a high flow rate and you spend a long time in there - consider fitting an eco shower head or flow restrictor.

We get away with heating our tank for about an hour and half in the mornings just before we get up and that gives us enough hot water for a couple of showers and hot water right through to the next morning (it will even last two days but the second shower on the second day is  a bit lukewarm).

How does it take so long to heat your water?  My boiler is on for 40 minutes a day.  Admittedly, if I have run the tank cold the previous evening, then it's not really as hot as it should be the next day, but it's usually enough.

I'm a light user of hot water.  Maybe if I used it more, the boiler might need to be on for 40 minutes twice a day.

matelodave

It usually heats in less than an hour (but a bit longer in the winter). It's a heatpump so the flow temp is only 50 degrees - we only heat the tank to 45 degrees. It only uses 1 to 1.5kwh when it does it. It boosts to 60 using an immersion once a week

smjxm09

60C is the temperature to kill bacteria In the tank so set it no higher and no lower.

Robin9

This is what we have to do in our village hall and we do a daily boost to ensure the stored temp 

HSE guidance https://www.hse.gov.uk/healthservices/legionella.htm

The primary method used to control the risk from Legionella is water temperature control.
Water services should be operated at temperatures that prevent Legionella growth:

• Hot water storage cylinders (calorifiers) should store water at 60°C or higher
• Hot water should be distributed at 50°C or higher (thermostatic mixer valves need to be fitted as close as possible to outlets, where a scald risk is identified).
• Cold water should be stored and distributed below 20°C.

Giblets

Thanks all!
Boiler seemed to be on  for about 1hr 30 in the morning, but no other times, so have switched off the immersion heater and put an extra 40min schedule later afternoon/ early evening. So far the better half has drained it once (leaving the hot water running whilst cleaning), so I got myself into trouble discussing not doing that lol

Out of interest, cylinder was from early 90's, and had a medium layer of insulation on it, none of the pipes in the airing cupboard were insulated, needless to say the airing cupboard was very warm, the pipes were hot to the touch and the cylinder certainly very warm to touch. As such I've picked up an insulation jacket (I had wrap the lengths horizontally around the jacket as the tank had been built in tight with the shelves!), and had some spare armaflex insulation tape (only 3mm thick but put on a couple of layers on) but the airing cupboard is now much cooler. The pipes (with insulation on) are only slightly warm and cylinder cool, feeling under the jacket the cylinder is nice and hot (so its not losing the heat at much).

matelodave

The more insulation you put on the less heat you'll lose

macman

Bear in mind that, in winter, heat loss from the airing cupboard is not really lost, as it heats the house.