The importance of following the heat pump design

In this video Jamie talks us through why it's important to follow the design for the heat pump and what the designs might include.

[@Allegedly2right]

My Combi no problem heat pump haha having a laugh why has it so many downfalls Heat Pump versus Combi,am I supposed to rip out all the pipework and radiators when for 10 years no problems nice and toasty.Heat Pump £20 to £25 per day Combi at the most £7.