Electric immersion- water not heating

Hi folks,


Know nothing about plumbing, any thoughts welcome.



Setup/issue:



- There’s two tanks you can heat through electrical immersion- a large one (bath- timer switch) and small one (shower/’boost’ switch)

- Bath tank never seems to get hot enough to use, which is a pain because it’s the one that works on the timer. We never use it as a result.

- For the shower the water seems to be getting heated reasonably ok, but the water coming out of the tap/shower only gets so hot, and gets lukewarm/cold very quickly. The ‘boost’ being on for an hour would only get you one reasonably hot shower (and we don’t hang about in there I promise)

- You can boost this by flushing the toilet or by running the cold tap in the sink, so the hot water is there but it’s not ideal as you can imagine, and not just because of the risk of a scalding

We’re renting, and I mentioned this to the landlady in the second week, but Murphy’s law when she came round to see what was what it worked perfectly (nb we did have the immersion on for a good two hours before her visit so y’know).

She suggested having it on for an hour on timer in the morning and boosting when needed, but as it’s just the two of us we really don’t need that much water heated that often- we really have a much greater need for a quick shower in the evenings but having a boost immersion switched on for 90 minutes each time seems really excessive for this.


If the consensus is that we should be heating the large tank on the timer for an hour every day and only using the ‘boost’ option as required then I’d listen but I’d want to be sure I’m not throwing money away if this isn’t going to be effective. If on the other hand the consensus is that electrical immersion just takes this long to heat water for two showers then fair enough- maybe I’ve been spoiled with gas before which only took 15 minutes to heat one good long hot shower!


Note- we seem to be in a very hard water area, judging by the buildup on kettle etc- is this a likely cause for problems in either heating/mixing water coming out of the tanks?


Any suggestions as to what the likely causes/fix are here would be greatly appreciated!

Wearb

Perhaps a picture of the whole hotpress might help.

Wearb

Wearb wrote: »

Perhaps a picture of the whole hotpress might help.

Will get that up! Wasn't sure how much would be overkill..

Wearb

It will be a starting point and pictures draw more attention to a post. It will most likely need an electrician to investigate the problem, but you never know if some of the lads here might spot something obvious.

Right here goes nothing:

Pete67

Presumably you have a day/night meter and can avail of cheaper night rate electricity? If so it would make sense to heat the water at night on the lower rate by using the timer. The night rate is from 11:00 pm to 8:00 am in winter (midnight to 9:00 am in summer) so if you set the timer to heat from say 6:00 am to 8:00 am you should have enough hot water to last the day. The cylinder is well insulated so will stay hot for a long time. Using boost during the day costs roughly twice as much per litre of water heated.

The shower pump will deliver around 10 litres of water a minute, so given the sink element only heats the top 1/3rd of the cylinder you would only have roughly 10 minutes of hot water for showering unless you use the bath setting.

Also worth checking that the thermostats in both elements are set to 60 degrees, if they are set lower the immersion will switch off too early and you won't get sufficient hot water.

That's plenty for me to be going on with Pete- thanks very much!