Aquasana AQ4000 FAQ
AQ-4050/AQ-4055/AQ-4056 Undersink Installation Kit
Do I need to use the faucet that comes with the undersink installation kit, or can I use another manufacturer's dispenser? Can I run the supply line directly to the inlet of the filter?
You can use any brand of faucet with Aquasana as long as it is a “vented” faucet, meaning the faucet has three tubes coming from the bottom. One tube runs from the supply line to the faucet, one runs from the faucet to the filter, and one runs from the filter back to the faucet. This type of faucet directs pressure to the filter only when the filter is in use. You cannot run water straight from the supply line to the filter because the system simply will not handle the pressure. The faucet is designed this way so that the filter unit does not have to bear the brunt of the pressure. Rather, the pressure is maintained in the faucet to prevent leaking or, worse yet, exploding filters.