Posted by: @01286p

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Hello,

We have a De Longhi Bran 0041MH ASHP and live in a highly insulated house in Shropshire.

Whilst the unit is excellent I would not reccomend purchasing one due to the total lack of Service Engineers for this Brand.

We have found that Service Engineers are biased towards the mechanics of the machine and have little real understanding of the programing of the controller other than what the manufacturer writes in the manual.

The program need substantial tweaking ,preferably done in Winter whilst the machine is operating near it's lowest temperature limits, for it to achieve the most economical operation.

Whilst we now have a unit that is operating at it's optimum there is still a problem in that whislt in standby mode it is consuming some 0.44Kw/hr which with the current astronomical cost of electricity equates to ...wait for it...£1392.

If anyone knows how to reduce stanby consumption I would be most obliged to hear from them.

 

Looking at the manual for your particular model, it would appear that the water pump has a maximum power demand of 0.42kW. I would suggest that you check the controller settings to see if the pump is set for continuous circulation.

@01286p

Check for any auxiliary heaters that may be operating below certain ambient air temperatures.

Thank you for that Derek, do you have any idea where in the Controller program / ladder I will find the setting for the pump and if so what should it be.

Thank you

Posted by: @01286p

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Thank you for that Derek, do you have any idea where in the Controller program / ladder I will find the setting for the pump and if so what should it be.

Thank you

I'm afraid that I am not familiar with your controller. Having had a quick look through the manual I cannot see anything obvious. I know that on some systems the water pump can be kept running to circulate the water around the system so that its temperature can be monitored. There is often the option to run the water pump periodically rather than continuously for this purpose.

I would suggest that, if possible, you monitor the energy usage when the heat pump is in standby, to see if it is a continuous 0.44kW, or if it is a higher value being switched on and off intermittently. Check to see if the energy consumption varies with changes in outside air temperature. Also see if the controller display gives any indication as to what may be operating.

@derek-m 

Thank you for that.Yes the circulating pump is running continuoulsly. I have checked that the 0.44 load is continuous via my meter.

I will now see if I can modify the program.

@01286p if it helps…. we noticed our HP had a defrost control which was set to act at a ridiculous  15degC. So we asked our call centre to assist in resetting it to a lower temperature. This stopped the circulating  pump from working all night. (Of course, that might not be your situation)

@sunandair 

Thank you for that.

I will give it a whirl.