Please explain immersion heaters to a simpleton

[Slinkie]

Hi all,

Having owned a house for the last 10 years with a combi boiler I have recently sold and moved into rented accommodation that has an immersion heater hot water system. Currently I have no hot water from our hot taps. The boiler is on (if that makes any difference) and the land lord has told me that all is ok and if I want hot water quicker I need to press the "boost button" and leave this on for 15 mins.

My understanding is that with this system that hot water should be instantly available and it is only limited by the volume of water in the tank. If I want to wash my hands after using the toilet and I haven't had the foresight to turn the boost on 15 mins before I get no hot water.

Surely this isn't correct? I am trying to get this resolved asap, it's critical at the moment as my wife is recovering at home from major surgery and so cleanliness is even more important at the moment.

 

[Bug One]

https://www.which.co.uk/reviews/home-heating-systems/article/home-heating-systems/immersion-heaters

 

[Freakbro]

Immersion heaters (in my simplistic terms) are just a big kettle.

You usually have them on a timer to come on for X amount of time, say, early in the morning and early evening to heat the tank of water (basically when you think you will need it). If you need hot water out of the times set, you use the boost button.

What is the timer set to at the moment?

Does the tank/pipes around it get hot?

 

[touch]

Mine takes several hours to heat up but there was no noticeable difference in electricity usage when I changed from turning it on/off as required to leaving it on 24/7

 

[bremen1874]

They switch themselves off when the water is up to temperature. If you don't use the water, and the insulation is good enough, the water will stay hot for a long time before needs to switch back on.

 

[psd99]

Mine takes several hours to heat up but there was no noticeable difference in electricity usage when I changed from turning it on/off as required to leaving it on 24/7

probably due to the thermostat that sits inside there, afaik it only draws a lot of leccy when the water needs warming up.

 

[Freakbro]

I think that's the eternal debate isn't it? Whether it's more efficient to leave it on 24/7 on thermostatic control so it just kicks in to top up the temperature compared to just heating the water from cold when required.

I dunno, I switched mine off years ago and don't use it as I don't really have any need for hot water from the tap

 

[psd99]

I quite like an immersion heater, especially when the if the boiler goes on the blink and you're left without boiler on a combi boiler system.

Good backup plan, but it takes up valuable space.

 

[Slinkie]

Thanks for all the replies, I have checked the settings and it is set to come on for 2 hours in the morning and 4 hours in the evening. I have extended these times however, having just tried to get hot water from the kitchen tap it never gets above slightly warm after running for 5 mins. The hot water is only used for sinks/ taps in the house as we have electric power showers in the bathrooms.

The landlord can only suggest we press the "boost" switch 15 mins before we need water however this is no good for washing hands after using the loo etc. I'm not really sure what the "boost" is but I don't want to leave it on all day if there's any detrimental effect on the system.

We've been in this house for just over 2 weeks and, due to my wife's surgery, have both been in hospital for 4-5 days of this. I'll have a look into the requirements of the landlord to provide hot water to us but that's another topic.

 

[Dave M]

If it's actually a power shower (pumped) then it's off your tank.

Boost just turns the water heater on for an hour, outside of the usual timer settings.

Just set the timer to be on all the time - either the tank loses heat quickly or you're using a lot.