The iSpring RCC7 ships with color-coded tubing (red, blue, yellow, black), compression fittings, a drain saddle clamp, a brushed nickel dedicated faucet, a 3.5-gallon storage tank, a TDS meter, and an extra set of pre-filters. The kit is complete for a standard under-sink install without any additional parts. You need an adjustable wrench, a drill with a 1-3/8" step bit (if drilling a new faucet hole), and a utility knife.
Pre-installation checklist
- Verify cold supply pressure is at or above 45 PSI. Below 45 PSI: add an RCC7P booster pump module before installing.
- Measure under-sink cabinet clearance: 15" wide x 11" deep x 18" tall for the manifold plus a 12" diameter x 15" tall tank. Confirm both fit simultaneously.
- Locate a power outlet if installing the RCC7P-AK (booster pump requires 110V).
- Identify the kitchen drain's horizontal run (the pipe between P-trap and wall) -- this is where the drain saddle goes.
Step 1: Cold water supply tap
iSpring includes a 3/8"-to-1/4" compression T-fitting that installs between the cold-water shutoff valve and the existing supply line. Shut off the supply valve, disconnect the existing supply line from the valve's output port, thread the T-fitting onto the valve's output port, reconnect the supply line to one port of the T, and push the blue (feed) tubing into the second port of the T-fitting. John Guest push-in fittings are used throughout -- push the tubing in firmly, pull gently to confirm the collar has seated. No thread tape required on compression or push-in fittings.
Step 2: Drain saddle installation
Locate the horizontal drain pipe run above the P-trap. Mark a spot on the top or upper side of the pipe -- not the bottom or side, to avoid back-siphon issues. Drill a 1/4" pilot hole using the included drill bit. Fit the saddle clamp around the pipe, aligning the saddle port over the drilled hole. Tighten both saddle bolts evenly -- firm hand pressure plus a quarter turn, alternating sides, until snug without cracking the pipe. Connect the yellow (waste) tubing from the manifold's drain port to the saddle using the included 1/4" compression fitting.
Step 3: Filter manifold assembly and mounting
The RCC7 manifold arrives with seven stage labels. Thread filter cartridges into housings in numbered order. Install stage 1 (sediment, white cartridge) in the first housing, stages 2 and 3 (carbon blocks, black or gray) in their respective housings, and the membrane (stage 4) in the membrane housing -- the membrane inserts with the longer end entering first. Stages 5-7 are post-filter and optional alkaline stage; follow the included diagram.
Mount the manifold to the cabinet wall using the included screws. The manifold should be positioned so filter housings hang down -- access to unscrew them for replacement requires the housings to rotate freely without obstruction. Leave at least 4 inches below the bottom of the filter housings for the filter wrench.
Step 4: Storage tank connection
Thread the brass tank fitting into the tank port (Schrader valve side). Verify bladder pre-charge pressure is 6-8 PSI using a tire-pressure gauge on the Schrader valve before connecting -- the tank ships pre-charged but occasionally loses pressure in shipping. If below 6 PSI, use a bicycle pump or air compressor to bring it to 7 PSI before connection. Push the red tubing into the tank fitting until it clicks, and connect the other end to the TANK port on the manifold output block.
Step 5: Dedicated faucet installation
If your sink has an extra hole: remove the existing plug, clean the hole edges, thread the iSpring faucet shank through from above. From below, slip on the rubber gasket, the mounting plate, and the mounting nut. Tighten the mounting nut hand-tight plus one full turn. Do not use a pipe wrench -- excessive torque cracks the faucet shank housing.
If drilling a new hole: use a 1-3/8" step bit for stainless steel sinks. Start slowly at low RPM with cutting oil -- heat buildup drifts the hole and dulls bits. For granite countertops, use a diamond core drill at very low speed with continuous water cooling from a squeezed sponge. The drill stops before you pull it -- the hole should be clean-edged, not cracked. Mark the drill site with masking tape first to prevent the bit from wandering.
Step 6: Final connections and flush
Connect the black (output) tubing from the manifold's post-filter outlet to the faucet's lower port. Verify all compression fittings are finger-tight plus a quarter-turn. Open the cold supply valve slowly -- watch every connection for 60 seconds for drips before opening the dedicated faucet.
Flush procedure: open the dedicated faucet and let the system run until the storage tank fills and the faucet flow slows to a trickle (tank full, system in shut-off). Empty the tank completely by opening the faucet fully. Repeat twice. First-cycle water appears gray from carbon fines -- this is normal and benign. After two flush cycles, test output TDS: should read 5-15% of source TDS. If not, check membrane orientation and re-seat tubing connections.
Booster pump installation (RCC7P-AK)
The pump module mounts inline on the blue (feed) tubing between the supply T-fitting and the manifold's feed inlet. Disconnect the blue tubing from the manifold feed port, cut the tubing at a point accessible for the pump module's two ports, and reconnect: supply side of tubing into the pump's IN port, new tubing from pump's OUT port to manifold feed. Connect the pump transformer (110V, included) to the outlet. The pump activates automatically when the system senses low back-pressure (tank filling) and shuts off when the tank is full. No switch or manual activation needed.