Not really having much information to go on when installing an ASHP on my flat roof, we decided to go ahead anyway.
Questions that arose were about things like will it blow over, can the warm roof take the weight, can the warm roof take all the vibration, will it wear away the EDPM, is the condensation OK to go into the soakaway, is there much maintenance required, how heavy is the ASHP, can we get it up there, can we get the power up there, will the control cables reach where we want them, can we drill through the roof to get the pipes into the utility room without going through any services, can we waterproof the water and cable pipes to the EDPM, can the pipes be insulated.
Well we couldn't find definitive answers to all these questions but we decided to do it anyway.
So far, if we were to install it again, I would add to the list auto vents to both the flow and return pipes just before the ASHP as one has not been enough, and fitting later is a pain in the ...
M.