Having just had a heat pump install comprising a 6.5kW Grant Aerona R290 paired with a 250 litre Newark super cylinder, this is my first post and I wanted to start by saying it’s great to have the chance to join the OEM community.
Over the past couple of weeks I’ve been experimenting with my hot water strategies. In wanting to have a single re-heat each day that’ll satisfy our daily demand, I’ve settled for 50ºC as a set point and have been running re-heats during the early afternoon on “silent level 2” having heard this is a good way to enhance the efficiency.
The cycle starts off with a fabulous COP of c. 6 but I’ve noticed that there is a sudden drop in the heat output when the flow temp gets to around 50ºC (see below) and I’m just curious as to what’s happening. I’m wondering if the throttling of the heat pump output on silent level 2 (40hz compressor speed and the 400 rpm fan speed) means that the heat pump is struggling to get the store temp above 45ºC? I’m going to try the same runs on silent level 1 next week to see what difference that makes.
Any thoughts and insights much appreciated!
