# My Journey to an efficient ASHP **URL:** \ **Category:** Heatpump\ **Created:** [15 February 2023 13:15 UTC](https://community.openenergymonitor.org/t/my-journey-to-an-efficient-ashp/22879 "2023-02-15T13:15:12Z")\ **Posts on this page:** 1\ **Showing post:** 94
**Author:** ![dMb](https://community.openenergymonitor.org/user_avatar/community.openenergymonitor.org/dmb/32/22999_2.png) [@dMb](https://community.openenergymonitor.org/u/dMb)\ **Post date:** [12 March 2023 09:33 UTC](https://community.openenergymonitor.org/t/my-journey-to-an-efficient-ashp/22879/94 "2023-03-12T09:33:02Z")
> [@Satwelsh](#): > > if the flow rate from the heat pump is 20ltrs then the flow rate to the zones needs to be 20ltrs OK, but if the UFH pump wants to move 15 litres and the Radiator pump wants to move 10 litres - but the Radiator pump is switching on-and-off then what does Nick try to match with the Charge Pump speed: 15? 25? 20 as as halfway house? I just can’t understand how a big, 2-pipe Buffer Tank piped as a ‘short circuit’ between Flow and Return is the right choice for Nick’s installation, whereas I _can_ understand how a smaller, 4-pipe Buffer Tank would isolate the multiple pumped circuits from each other - something like the black tank shown in this other thread (which appears not to need it, since it only has a single emitter circuit). > [@11.2kW monobloc R32 Ecodan showing COP2?](https://community.openenergymonitor.org/t/11-2kw-monobloc-r32-ecodan-showing-cop2/23031): > > Friend asked me to come round and look at their 11.2kW R32 Ecodan. Heat loss for house is 9.9kW at -3C outside. So the good news House is warm (20C), lots of big K2 rads It’s long running, hours at a time DT is showing around 5 when running. unit is using weather comp with flow at around 40C at 6C outside It’s mainly open system/rads but with a weird 12L 4 port buffer. Although the flow/return seems to be okay across that. I’m not sure what that is adding? Might be better to think abou… --- _[View the full topic](https://community.openenergymonitor.org/t/my-journey-to-an-efficient-ashp/22879)._