Heating water... Best way

witchwood

We are looking for a new way to heat our water. We only use it for showers and washing up etc. Not heating. We currently have an unvented immersion tank. We think this is a very expensive way to heat the little water we use. We are not on mains gas here. Was wondering about a lpg tank with a boiler. Was also thinking about connecting a back boiler to our wood burner, but that would mean either having the burner going all year, or switching back to electric water in the summer when we don't need the wood burner. We live in a heavily wooded area and solar panels are not an option either. Any suggestions gratefully received. 

lohr500

How are you heating the house?  

witchwood

lohr500 said:

How are you heating the house?  

Woodburner. We live in a small log cabin, and so not many rooms to heat. 

Alnat1

How long do you heat the water for each day and what temperature is the tank set at?

witchwood

Alnat1 said:

How long do you heat the water for each day and what temperature is the tank set at?

The thermostat hasn't got a temperature gague... just a + or -. It is on all the time... the thermostat just kicks in when temp drops. 

ctdctd

Put a time switch on the immersion heater and organise your day to try and have showers and washing up at about the same time.

Then set the timer for the minimum period required to get enough hot water - this will get your existing electricity usage as low as possible. Check how much this saves and then decide if a different method would be more economical.

witchwood

ctdctd said:

Put a time switch on the immersion heater and organise your day to try and have showers and washing up at about the same time.

Then set the timer for the minimum period required to get enough hot water - this will get your existing electricity usage as low as possible. Check how much this saves and then decide if a different method would be more economical.

All of those are good ideas. Thank you. It does have a timer on it... just we have never used it! Simple things that I guess we already knew. Showers and washing up are all done in the evenings anyway and so half way there.  Hopefully will save us a few and the hassle of of different methods. 

Alnat1

We gradually reduced the time the tank is heated, now find 40 mins in the morning is plenty for 2 showers and hubby's shave. Can always boil a kettle for washing up if needed.

As there's a thermostat somewhere on the tank, you say it turns on and off so it should be possible to alter the temperature setting somehow. Is there a make/model number you can google? We have ours at 50C.

witchwood

Alnat1 said:

We gradually reduced the time the tank is heated, now find 40 mins in the morning is plenty for 2 showers and hubby's shave. Can always boil a kettle for washing up if needed.

As there's a thermostat somewhere on the tank, you say it turns on and off so it should be possible to alter the temperature setting somehow. Is there a make/model number you can google? We have ours at 50C.

We need 4 showers a day, well 2 of us most days and the kids when we throw them in there! In the winter we have a kettle on the go on the wood burner all the time so we actually boil the electric kettle less. 
Was told temp has to be at least 60c to kill off bacteria and legionnaires in the pipes? 

doodling

Hi,

witchwood said:

Alnat1 said:

We gradually reduced the time the tank is heated, now find 40 mins in the morning is plenty for 2 showers and hubby's shave. Can always boil a kettle for washing up if needed.

As there's a thermostat somewhere on the tank, you say it turns on and off so it should be possible to alter the temperature setting somehow. Is there a make/model number you can google? We have ours at 50C.

We need 4 showers a day, well 2 of us most days and the kids when we throw them in there! In the winter we have a kettle on the go on the wood burner all the time so we actually boil the electric kettle less. 
Was told temp has to be at least 60c to kill off bacteria and legionnaires in the pipes? 

If, as you state, the system is unvented then legionella is much less of a concern as the water will remain chlorinated until it is used.

If the immersion heater is mounted in the side of the tank towards the bottom then it is also highly likely that if it is set to (say) 50C then the top of the tank will reach 60C+. (To be honest the numbers on the thermostat should be considered a guide and should really be checked with a thermometer in any event if the precise temperature is important to you).

If hot water is your main use of electricity then you might want to consider heating overnight on economy 7 but you need to do the maths - it isn't always cheaper.