Immersion heater very little hot water

[orangemars2000]

I moved into a flat over a month ago now and realized when trying to take a shower that there was little to no hot water - at this time I would turn the water on full out, it would stay cold for maybe 30 sec, it would then get noticeably warmer (lukewarm) and then run out again in maybe 15 seconds.

I reported the issue and had someone attend who said that something had been tripped in the heater, he reset it and said it would take a while to heat up but it would be fine. The next morning it got much hotter much faster - to the point where it was scalding/uncomfortable on full heat - only to then promptly run out and be back to lukewarm in under a minute. As this was an improvement I tried to make do, but given that I was still shivering in my shower I reported that the issue hadn't been resolved.

They reattended yesterday, bled the thing, and told me everything was working fine. They even showed me and had a lot of hot water coming out for longer than I'd ever gotten it with no signs of running out. He also had me touch a little copper faucet on heater to show me it was getting hot (?). Before leaving they noticed that the timer was set for only 1 hour, so they put it longer and told me that would fix the problem.

This morning I was greeted by a return to how things were before they attended the first time - a long while to heat up just a bit before petering out. I'm at my wits end here, these contractors seem to be useless but I don't really have a reason to doubt when they say it is working correctly. I only yesterday discovered the little control panel with the settings, is this something that I can fix by setting it properly, or do I need to give in and get a plumber I'm actually paying to come take a look? I've only touched it to confirm that the schedule is now set to between 3:15-8:15, 8:16-9:16.

Thanks for the help, I've put some pictures of the heater/panel below:

 

[SJB060685]

If you knew the cylinder volume and immersion heater power in watts you could calculate how long it would take to heat up. Typically you would time to heat the water in advance to your usage. If you showered at 7am and the cylinder required an hour to heat up then you would time it from 6am to 7.30 for example. You seem to have adjusted the times but if you’re still having Luke warm water problems then you could have a faulty immersion heater, possible loose connection etc.
To avoid further nuisance problems I would have a decent plumber attend, or an electrician.

 

[orangemars2000]

If you knew the cylinder volume and immersion heater power in watts you could calculate how long it would take to heat up. Typically you would time to heat the water in advance to your usage. If you showered at 7am and the cylinder required an hour to heat up then you would time it from 6am to 7.30 for example. You seem to have adjusted the times but if you’re still having Luke warm water problems then you could have a faulty immersion heater, possible loose connection etc.
To avoid further nuisance problems I would have a decent plumber attend, or an electrician.

Sticker on the side says:
2.7 kW 230v / 3.0 kW 240v (for both timed boost and off peak)
And primary store capacity: 150L.

I'll try to calculate that myself when I have time, seems a bit complicated but would be good to know.

That's what I was afraid of - annoying that this is definitely meant to be the landlord's problem.

 

[SJB060685]

Sticker on the side says:
2.7 kW 230v / 3.0 kW 240v (for both timed boost and off peak)
And primary store capacity: 150L.

I'll try to calculate that myself when I have time, seems a bit complicated but would be good to know.

That's what I was afraid of - annoying that this is definitely meant to be the landlord's problem.

Quick calculations suggest a 2.7kw immersion will heat 150 litres in around 3 and a half hours.

 

[ShaunCorbs]

Don’t you have a thermostatic shower ? Or is it just manual

 

[John.g]

There may be two heating elements with the upper one only heating say 50 litres or so or the element(s) may just be tripping out after a very short period, even 50 litres at 60C should give a 40C shower for ~ 8 minutes at a flowrate of 10LPM.
Can you monitor your elec meter when its supposed to be on.

 

[orangemars2000]

Don’t you have a thermostatic shower ? Or is it just manual

No idea sorry, but looking at it I would certainly guess manual!

 

[orangemars2000]

There may be two heating elements with the upper one only heating say 50 litres or so or the element(s) may just be tripping out after a very short period, even 50 litres at 60C should give a 40C shower for ~ 8 minutes at a flowrate of 10LPM.
Can you monitor your elec meter when its supposed to be on.

From everything I've gathered about this model etc. I do believe that there are 2 heating elements, there's a "boost" button that should turn the top one on for an hour. From what I can tell they've programmed a "timed boost" from 7am to 11pm which is meant to turn on the top element and the boost button is red as if it were activated during those times. Left it today to see if maybe the top element worked better than the bottom, but just checked and fails to get past lukewarm. Have shut off the timed boost since I don't need that wasting my electricity anyway.

Unfortunately the meter is in a cupboard down the hall, I need to ask the concierge for keys to access it. Not troublesome once in a while but monitoring continuously is a bit difficult.

 

[John.g]

If the boost element is heating the top half of the cylinder, say 75 litres, then 2.7kw should heat the water from 15C to 60C in 1.5 hrs or from 15C to 46C if you just hit the "one hour" boost button, you can easily see where this element is located, height wise in the cylinder.

 

[Murdoch]

You need to establish if both heating elements are actually working.

Those controllers fail, the meter could have changed and you don't have e7 , one of the immersions could have failed