Reverse Osmosis Installation Checklist: Preflight and Final Inspection

Use this as a pre-installation and post-installation inspection list for a drinking-water, point-of-use reverse osmosis system. For the plumbing sequence, illustrated techniques, startup and troubleshooting, follow the full under-sink RO installation guide linked below and the exact manufacturer's manual.

During a new kitchen build or renovation, document the planned cold feed, shutoff access, approved reject-water connection, faucet opening, cabinet depth and height, service clearance, and an outlet if the selected model requires power. Review the plans before counters, cabinets, and drain assemblies make changes expensive.

Identify the reason for treatment using a current water report or suitable lab analysis, especially for private wells. Verify that the exact model has a current listed reduction claim for the contaminant and that your feed water meets its pressure, temperature, hardness, chlorine and other operating limits.

Check whether the chosen kit is tank-based, tankless, powered or countertop. Do not assume every RO system has the same dimensions, drain connections, membrane changes, or flush procedure.

Compare the unboxed parts with the exact kit diagram and dry-fit the intended layout. Make sure the filter and any tank can be removed without cutting tubing or shifting cabinets. Keep a bucket, towels and bright flashlight ready for the final leak inspection.

Check whether the faucet can use a permitted existing hole. Drilling stone, porcelain or other specialized surfaces and changing drain assemblies may require a licensed or qualified installer. Sealants are not universal: follow the manual for gasketed, push-fit, compression and threaded joints.

Follow the model's step-by-step installation manual with the cold-water feed isolated and depressurized. This inspection list checks the finished connections; it is not a substitute for the manufacturer's fitting instructions or locally required plumbing design.

An RO discharge may require a specific air-gap arrangement, and drain saddles are not allowed everywhere. Verify the approved connection and any backflow protection required locally before running the system. Do not use generic thread tape on every fitting.

Open the feed only as the manufacturer directs, inspect joints using a dry paper towel, and complete the exact model's first-flush or tank-cycle procedure before drinking. A universal number of flush gallons or tank fills cannot be applied to all models.

Reinspect the cabinet during the first run and after the unit reaches its normal operating state. If water escapes, close the feed valve and correct the source before use. If a health-related contaminant prompted installation, plan a suitable post-treatment test with a certified laboratory.

Before putting the area back into use, save the manual and part numbers and record installation, flush, inspection and testing dates. Set maintenance reminders using the exact cartridge's capacity and calendar limits, not generic time intervals.

If an inspection reveals leakage, shut off the water and use the manufacturer's troubleshooting procedure or call a qualified plumber. The separate full installation guide covers the detailed plumbing and startup sequence, and the troubleshooting guide addresses persistent low flow, air and drain issues.