The other thing I've noticed is that the flow rate seems to go up much higher when it appears to switch on and off.

What I mean is, just now it was off with a flow rate of very low.  It then kicked in and accelerated quickly to 30 and is now whirring away again.  In a bit it will stop altogether for a few minutes (flow drop to zero) and then it all fires up again to a very high flow rate.  

This morning, when it was quiet, it just maintained a constant flow rate and didn't come on and off like it is now.

Ah - @derek-m will be able to sort you out ! Is that number on the outdoor unit ? and is there a similar number on the indoor unit. It looks like there's a shelf or something under it which might cover it up, so you could look on the Information screen possibly under 'About' ? That'll help with getting the right manual which will have the correct flow rate.

Posted by: @bridgetjohn

The other thing I've noticed is that the flow rate seems to go up much higher when it appears to switch on and off.

What I mean is, just now it was off with a flow rate of very low.  It then kicked in and accelerated quickly to 30 and is now whirring away again.  In a bit it will stop altogether for a few minutes (flow drop to zero) and then it all fires up again to a very high flow rate.  

This morning, when it was quiet, it just maintained a constant flow rate and didn't come on and off like it is now.

 

 

Hi Bridget,

Your heat pump is rated at 11kW, which is the maximum heat energy output when running at full power.

I believe that your heat pump is set for a fixed water flow temperature control, which is far from ideal. I would suggest that you set your system for weather compensation control, which is much more efficient. Newbie may be able to help you if you are not certain how to make the adjustments.

What control do you have on your system? Do you have thermostats and TRV's?

@heat-pump-newbie

 Hi, pictures of outside unit label and the two labels on the inside unit in airing cupboard.  Thanks for the advice so far.

@derek-m 

There is a honeywell thermostat system with a remote control which is talking to the system to set the temperature.

The radiators themselves do seem to have controls on them - but I've not messed with those.  The only one I've tried to adjust is the towel rail and that just causes issues in the airing cupboard pipes and the snoring to resume, so that's fully open now.

one more from inside tank

Posted by: @bridgetjohn

one more from inside tank

Hi Bridget,

I cannot clearly see the model number on the photo, but I believe this may be a backup heater, which you should not use except as a final resort since it will cost an arm and a leg to run.

Hi @derek-m and @bridgetjohn Now I realise your controller is a separate unit, the black box on the wall - mine is a split system whereas yours is a monoblock (I'm still a newbie !). However this from the Installer Reference Manual shows what your flow rates should be...

 Over to you Derek, again...!

Posted by: @bridgetjohn

@derek-m 

There is a honeywell thermostat system with a remote control which is talking to the system to set the temperature.

The radiators themselves do seem to have controls on them - but I've not messed with those.  The only one I've tried to adjust is the towel rail and that just causes issues in the airing cupboard pipes and the snoring to resume, so that's fully open now.

Hi Bridget,

Is your system still creating noises?

Does the heat pump switch on and off fairly frequently even when it is quite cold outside?

How technical are you?

@derek-m Hi yes, it's still making noise from the water pumping round the system at 30+l/min.

Yes it seems to switch on and off.

Technical - not very.  

Posted by: @bridgetjohn

@derek-m Hi yes, it's still making noise from the water pumping round the system at 30+l/min.

Yes it seems to switch on and off.

Technical - not very.  

Hi Bridget,

I suspect that your system has not been configured correctly and may need to be optimised.

When you have time could you do the following:-

Record the length of time the heat pump runs and how long it is then stopped.

After it starts running monitor the data on the information screens and record the values and any changes.

If you could do this for possibly a 2 hour period it may provide some useful information.

Hi @bridgetjohn - Also could you post a photo of the Home screen (with the house pic).

Turn left dial to the Main submenu, click left gives a circle diagram, photo that.

Click left again, choose Setpoint Mode and click left, photo that.

Thanks - all helps to see what's going on. It won't make any changes.