A2A HP is a split unit with an indoor unit and an outdoor unit with refrigerant lines going through the wall of your house. I put such a system in recently and there is a thread about it here.
https://camelot-forum.co.uk/phpBB3/view ... =17&t=1043
A monoblock ASHP is a single unit with all the refrigerant stuff sealed in a single unit and it simply pumps hot water into the house for radiators, hot water tank or underfloor heating. I also have a thread about a monoblock HP but it is a GSHP rather than an ASHP. They are typically a lot heavier than A2A HPs so almost always they are ground sited outside.
https://camelot-forum.co.uk/phpBB3/view ... f=17&t=487
Maybe the confusion is that there are also some A2A HP monoblocks which are sited inside, with an air inlet and outlet through the wall but I would not recommend them as they are, expensive, noisier inside and are less efficient.
PS - Like the pussys.
