Sunamp UniQ HW Problem

[RLightbown]

I have a Sunamp UniQ installed with a Daikin Altherma H HT 16kw heat pump for hot water supply

The UniQ model is : UniQ HW 12+ILTHP-DN

It has been installed for 2 years without any problems, but I have recently noticed that the UniQ starts being reheated by the ASHP, but after some time switches over to the internal electric heater which of course is an expensive way to heat hot water.

The Sunamp Uniq doesn't appear to have any user changeable settings.

Does anybody know of any way to stop this happening

 

[ReedRichards]

Well you think the Sunamp is being reheated by the ASHP but the Sunamp thinks it has been waiting for heat to the point where it give up and takes matters into its own hands.  So perhaps there has been a valve failure so heat from the ASHP doesn't reach the Sunamp or a blockage so heat doesn't get there fast enough?  Or there's a problem with the Sunamp.  Could a temperature sensor have failed?  I heard a rumour that some units have an internal pump; could that (if it really exists) have failed?   

[RLightbown]

I have discovered a wiring link in the Sunamp that when connected causes the Heat pump input to timeout at 45 mins & switch to immersion heater.

Removing the link stops this happening. If you do need a n Immersion boost at any time it can be done in the Daikin Onecta Smartphone app

 

The Sunamp is designed so it first recharges from the heat pump, and after 45 mins if not fully charged it will activate the immersion to finish the charging. You can however disable this function, as described on section 3.8, page 36, table 16.2. of the manual 

You will need to remove link 3 to disable the heater backup option.

 

Here is the manual for my Sunamp: https://sunamp.com/en-gb/wp-content/uploads/sites/2/2022/03/D0056-1-Thermino-hp-DN-SG-Heat-Batteries-Installation-and-User-Manual.pdf