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Posted by: @julesmp8So there appears to be only 2 options left available. Prepay Immersun £179, send the unit to them and hope they can fix it (they quote a 85 - 90% success rate; charging either way).
Buy something else to do the same thing.
That’s very disappointing because the Immersun is not cheap to begin with. I came across a new brand this week. Will see if I can dig it up.
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Posted by: @editorPosted by: @derek-mDid you get your faulty unit repaired? What was the fault?
Yes, they repaired it. I enquired what the issue was but they said that they didn’t get a report from the repair team - it was clear they didn’t want to share what the cause was.
Whilst I am pleased with the Immersun unit itself, I am far from impressed with their customer care. About two weeks ago the Historical data stopped being updated, although the Live data is still working fine. I have sent quite a number of polite e-mails asking for the problem to be rectified, but just keep receiving the same BS message.
Some years after I purchased mine the company was taken over and I suspect that the manufacturing quality may not be the same. Maybe they are now being made in China? What is the country of origin on the manufacturers nameplate?
@julesmp8 here’s the other diverter I recently came across. I know absolutely nothing about it.
@derek-m I’ll check the manufacturer plate tomorrow to see where ours was made, but I think we all know what the answer will be.
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How Installing a Heating System Became a National Nervous Breakdown
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Rewritten and updated for 2027
📘 From Zero to Heat Pump Hero
🛠️ Bodge Buster
New to heat pumps?
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Thanks for all the info.
I am not too impressed with IMMERSUN to be honest. As mentioned they want pre-paying before they even look at it, they do not commit to actually fixing it but you pay anyway and if they do fix it, they offer no guarantee on the repair.
I really do not want to pay to get this fixed and find it fails again soon after.
How long ago did they fix yours?
My Immersun unit has never failed from an operational point of view. Occasionally the monitoring system fails to supply the data to my laptop, which sometimes takes several weeks to get rectified.
I can't remember if it was late 2015 or early 2016 when I purchased and installed the Immersun unit, but I'm fairly certain that it was before the change in ownership and probably management. Whether the design and manufacturing has been changed I cannot comment.
@julesmp8 I don’t blame you at all. Our repair took just over a week including sending and receiving via DPD.
I don’t blame you at all for not wanting to pay a significant amount for a repair of what is still a relatively new unit. This smacks of our Samsung fridge drama. Paying to repair something that shouldn’t be broken already, and given I had the same error code, which was repaired quite quickly, possibly hints at an underlying issue.
🔥 Britain’s Heat Pump Shitshow
How Installing a Heating System Became a National Nervous Breakdown
Pre-order with free UK shipping.
Rewritten and updated for 2027
📘 From Zero to Heat Pump Hero
🛠️ Bodge Buster
New to heat pumps?
Take the Heat Pump Fundamentals course and use INTRO50 at checkout for 50% off.
@julesmp8 we installed the diverter in March 2023. I reported the error on June 25, 2023. Did the resets and other things they wanted. Unit was collected on July 7, 2023, by courier and returned on July 16, 2023.
🔥 Britain’s Heat Pump Shitshow
How Installing a Heating System Became a National Nervous Breakdown
Pre-order with free UK shipping.
Rewritten and updated for 2027
📘 From Zero to Heat Pump Hero
🛠️ Bodge Buster
New to heat pumps?
Take the Heat Pump Fundamentals course and use INTRO50 at checkout for 50% off.
@julesmp8 what have you decided to do?
🔥 Britain’s Heat Pump Shitshow
How Installing a Heating System Became a National Nervous Breakdown
Pre-order with free UK shipping.
Rewritten and updated for 2027
📘 From Zero to Heat Pump Hero
🛠️ Bodge Buster
New to heat pumps?
Take the Heat Pump Fundamentals course and use INTRO50 at checkout for 50% off.
I was on deemed export and had an immersun that blew up after 7 years, had a similar experience with support, pre pay with no guarantee of a fix, I declined.
I sold the defunct immersun unit on Ebay for £80 and moved my deemed export that was only worth £80 a year to metered export at 15p per kwh with Octopus and have now turned the immersion heater off.
Quite remarkably it appears that our Immersun has now stopped working again. Different thing this time. The tank now reheats itself with excess solar and the Immersun shows our tank as "HOT". As the day progresses and we use water, the tank temperatures drops (which I can see from our heat pump menu) but the Immersun still shows the tank as "HOT".
So I've factory reset the unit in the hope that it would fix things, and now I'm getting a new error: Error 3 Heater Not Detected.
I've checked to see if any wiring has come loose (which was hugely unlikely because we hardly ever access this area) and everything is connected properly with no visible issues.
I couldn't remember how to factory reset the unit and couldn't find it in the manual so here is how to reset the Immersun for those that come across this post in the future:
From the Home Screen click "tick" and go to Menu -> Advanced Settings -> Passcode 0000 -> Factory Reset -> Tick 'RESET CONFIG' & Tick 'RESET IMMERLINK' and the select Execute.
🔥 Britain’s Heat Pump Shitshow
How Installing a Heating System Became a National Nervous Breakdown
Pre-order with free UK shipping.
Rewritten and updated for 2027
📘 From Zero to Heat Pump Hero
🛠️ Bodge Buster
New to heat pumps?
Take the Heat Pump Fundamentals course and use INTRO50 at checkout for 50% off.
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