@markc 

Well done Mark for discovering that fact, though it would have been useful if Mitsubishi had mentioned it in the manual, or did I miss reading that bit.

I would have been surprised if a company like Mitsubishi had released a product to the market without fully testing it, but stranger things have happened.

Using this newly discovered fact, it is possible to see how well the ASHP is following the weather compensation, by checking if the actual water flow temperature is as requested by the curve.

@derek-m as a note you can use the function "FORECAST" in excel to recreate this chart. All you need are the two set points and a desired value e.g. 5 degrees outside and it will give you temperature.

https://library.mitsubishielectric.co.uk/pdf/book/ATW_Databook_R32_2020#page-62-63

All, this document has all you need to know about Ecodan ASHPs. P62 has the COPs at different flow and ambient temps for the 14kW version.  If you go back a few pages there is an explanation of some of the terms used.  It's a bit technical but gives an idea of the sort of COP you can expect and therefore maybe an idea of what to aim for in your setup.   

@justinsb @kev-m @derek-m

Hi all - we're about six weeks into our ASHP install - ecodan 14kw. We've got a flow temp of 40* and cop ranges from 2.5 to 3 - it's very rarely gone above three. I've read the above - bit nervous about going right in there with some of the settings - would any of you be able to advise - what should I try first re trying to up the cop? Grateful for any help, thanks. 

@rv3 is your weather compensation turned on? That would be step 1

Posted by: @rv3

@justinsb @kev-m @derek-m

 

Hi all - we're about six weeks into our ASHP install - ecodan 14kw. We've got a flow temp of 40* and cop ranges from 2.5 to 3 - it's very rarely gone above three. I've read the above - bit nervous about going right in there with some of the settings - would any of you be able to advise - what should I try first re trying to up the cop? Grateful for any help, thanks. 

Hi RV3,

Welcome to the forum.

As Batalto suggested, first check if weather compensation is selected on the main controller. How familiar are you with the main controller and the operators manual?

Where is your main controller located and do you have any other controls such as thermostats and TRV's?

If you are not certain about how to make adjustments then please let us know and we will guide you through the process. The important thing before making any changes is to make a note of the original settings and record what you do so that should you make any mistakes the original settings can be restored.

Posted by: @rv3

@justinsb @kev-m @derek-m

 

Hi all - we're about six weeks into our ASHP install - ecodan 14kw. We've got a flow temp of 40* and cop ranges from 2.5 to 3 - it's very rarely gone above three. I've read the above - bit nervous about going right in there with some of the settings - would any of you be able to advise - what should I try first re trying to up the cop? Grateful for any help, thanks. 

@rv3, I have the same ASHP as you.  At that flow temp, a COP of around 3 sounds about right; it's about what I got.  I assume at that temp you have radiators?  Were they sized for the ASHP or was it a retrofit to a boiler based system?  Are you heating your house for periods and letting it cool or heating it constantly?  At the moment, we are able to heat our house with flow temps of less than 30 but our rads were all specified with the ASHP.

You should be able to achieve a better COP by lowering the flow temps either manually or by using weather compensation but you may have to have the heating running for longer.

As Derek says, don't worry about changing these sorts of settings; it's easily changed back.     

Is the Ecodan Auto Adaptation feature the same as the Weather Compensation feature?

Taken from current brochure

Posted by: @jeff

Is the Ecodan Auto Adaptation feature the same as the Weather Compensation feature?

Taken from current brochure

Hi Jeff,

The simple answer is No. Auto Adaptation is a combination of both weather compensation and room temperature control.

Basically, the controller measures both the outside air temperature and the indoor air temperature. If the outside air temperature were to reduce then the controller would automatically start to increase the water flow temperature, by an amount determined by the slope of the weather compensation. If the slope of the weather compensation is not exactly correct, then there could be an increase or decrease in the indoor temperature. Auto Adaptation allows the controller to counteract any variation in indoor temperature that may occur, since the controller also measures the indoor temperature, and if the temperature starts to rise above the setpoint, it would automatically reduce the water flow temperature by a small amount until the desired indoor temperature is achieved.

Auto Adaptation will also help reduce the effects of solar gain, wind chill, rain and human activity, which weather compensation by itself would not be able to do.

Posted by: @derek-m

Posted by: @jeff

Is the Ecodan Auto Adaptation feature the same as the Weather Compensation feature?

Taken from current brochure

Hi Jeff,

The simple answer is No. Auto Adaptation is a combination of both weather compensation and room temperature control.

Basically, the controller measures both the outside air temperature and the indoor air temperature. If the outside air temperature were to reduce then the controller would automatically start to increase the water flow temperature, by an amount determined by the slope of the weather compensation. If the slope of the weather compensation is not exactly correct, then there could be an increase or decrease in the indoor temperature. To counteract any variation in indoor temperature that may occur, the controller also measures the indoor temperature, and if the temperature starts to rise above the setpoint, it would automatically reduce the water flow temperature by a small amount until the desired indoor temperature is achieved.

Auto Adaptation will also help reduce the effects of solar gain, wind chill, rain and human activity, which weather compensation by itself would not be able to do.

Thanks. Makes sense given they also say this.

Would you also recommend the auto adaptation mode as they are recommending  rather than the more basic weather compensation mode? 

@jeff 

Hi Jeff,

If you wish to have accurate indoor temperature control, then it would be best to use Auto Adaptation control.

Whether you can just set your system to 'Room' (Auto Adaptation) control, depends on your system and where your main controller is located. To be able to use Room control successfully, your main controller needs to be located in the room whose temperature you wish to control, or you need to add either a temperature sensor or a wireless remote controller, both of which are optional extras.

Posted by: @derek-m

@jeff 

Hi Jeff,

If you wish to have accurate indoor temperature control, then it would be best to use Auto Adaptation control.

Whether you can just set your system to 'Room' (Auto Adaptation) control, depends on your system and where your main controller is located. To be able to use Room control successfully, your main controller needs to be located in the room whose temperature you wish to control, or you need to add either a temperature sensor or a wireless remote controller, both of which are optional extras.

Do you think it will be cheaper to run than just using Weather compensation alone as Mitsubishi say?

Any idea what % difference it might make based on your experience? It might help in the decision process for future changes/installs for some.