Accumulator (Diaphragm) Tank Vs Pump?

[jimmycooker]

I have a vented unzoned central heating system in my small 3 bedroom house.

I have just built a granny flat out back (nearly the same size) and have run pipes and wiring from both buildings to a boiler house.

I want to relocate the boiler (or install a new condensing boiler) in the boiler house along with a hot water tank that will feed both buildings.

To maintain hot and cold water pressure in both buildings without any pressure / flowrate drop if both buidlings are using water, what do i need to install. Can i avoid the need for pumps and use an accumulator tank with a diapdragm, or would i need a pump also?

Thanks,
James.

 

[ecowarm]

What flow rate and pressure do you have at the moment