What matters
The length of the longest pipe run, the number of inlets and floors, carpet versus hard floors, and the hose and powerhead you use.
Reading the specs
Airwatts combine airflow and suction. Water lift shows sealed suction, useful for carpet and long runs. Airflow (CFM) shows how much air moves. All three are published by the manufacturers on our Systems page.
Do not undersize
A unit that is too small for long runs feels weak at the far inlets. We size the unit at the quote visit. The system selector gives a starting point.