A water treatment contract can describe an impressive solution without clearly identifying the equipment you are buying. Phrases such as whole-house filtration, premium softener or advanced drinking water system sound specific, but they do not tell you enough to verify the installation later.
Before signing, ask the company to include an equipment schedule in the contract or in an attached document that the contract specifically incorporates. This schedule should identify every major component, its intended job and the important details needed to recognize it. The goal is not to turn the contract into a technical manual. The goal is to make the promised installation verifiable.
Start with the water problem the equipment is meant to address
The paperwork should connect each proposed component to a finding from your water test or to a clearly stated household goal. One tank might be intended to reduce hardness. Another might address iron, sediment, chlorine, taste or odor. An under-sink system might serve only one drinking water faucet.
Ask the provider to list the treatment target beside each component. If the proposal includes equipment that does not connect to a test result or a goal you discussed, ask why it is necessary. If a tested issue has no corresponding treatment step, ask how the system is expected to address it.
Avoid relying on broad language such as improves water quality. The contract should state what the equipment is intended to do without promising results that cannot be measured or confirmed.
Require a model number or an equivalent identifying description
For packaged equipment, the schedule should include the manufacturer and complete model number. Record the control valve model separately when the valve and treatment tank come from different manufacturers. Many systems look similar from the outside, so a brand name or cabinet color is not enough.
Some dealers assemble systems from separate tanks, valves, media and fittings. In that case, a single model number might not exist. Ask for a component description that provides the same level of clarity. It can include the tank size, control valve, media type, media quantity, brine tank and any separate prefilter or post-filter.
If the company reserves the right to substitute equipment, the contract should explain what counts as an acceptable substitute. Look for measurable requirements such as treatment function, capacity, flow rating, certification and warranty coverage. A statement allowing comparable equipment without defining comparable gives you little protection against a meaningful downgrade.
List every tank, filter, faucet and accessory
The equipment schedule should cover more than the largest tank in the room. Ask whether the quoted price includes each of the following items that applies to your project:
- Treatment tanks and their media
- Control valves, meters and electronic controllers
- Brine tanks, safety floats and overflow fittings
- Cartridge filter housings and the first set of cartridges
- Ultraviolet chambers, lamps, sleeves and monitoring equipment
- Reverse osmosis storage tanks, faucets and membrane assemblies
- Booster pumps, pressure tanks or flow controls
- Leak sensors, automatic shutoff valves and alarms
- Bypass valves, isolation valves and sample ports
- Drain fittings, air gaps and discharge tubing
This level of detail prevents a common misunderstanding: the homeowner assumes a useful accessory is included while the contractor considers it an optional upgrade. If an item was shown during the sales visit but is not included, the contract should say so.
Put media details in writing
When treatment depends on media inside a tank, the outside label does not always reveal what is inside. Ask the contract to identify the media type and quantity. For a mixed-media tank, request the type and approximate amount of each layer or ingredient.
This matters when you compare the installed system with the proposal, order future service or evaluate a replacement recommendation. It also helps another service company understand what the original system was designed to do.
Ask whether any media requires periodic replacement and whether the quoted price includes only the initial fill. If replacement is expected, request the product name or specification needed to obtain the correct material later.
Confirm capacity and service-flow language
Capacity can mean different things depending on the equipment. It might refer to hardness removal between regenerations, contaminant reduction before media replacement, storage volume or the amount of water that can pass through the unit at an acceptable rate.
Ask the contractor to label each number rather than writing capacity by itself. The paperwork should also state the assumptions behind the selection, such as household occupancy, tested water conditions, plumbing size and expected peak water use.
If the proposal lists a flow rate, ask whether it is a service flow rate, a maximum flow rate or the minimum backwash flow required by the equipment. Those figures answer different questions. A high maximum number does not prove that the system can treat water effectively at that rate.
Identify which plumbing fixtures will receive treated water
The contract should state where the system connects and which water lines it will serve. Clarify whether treatment includes hot and cold water throughout the house, only selected fixtures or only a dedicated drinking water faucet.
Ask specifically about outdoor faucets, irrigation, the kitchen cold line, refrigerator water, ice makers, utility sinks and any detached building. If a fixture will remain untreated, put that exception in the scope.
This is also the place to document whether the installer will reroute plumbing. A treatment tank can be installed correctly and still fail to serve the fixtures you expected if the home has split plumbing or an unusual pipe layout.
Record operating settings and startup work
Some equipment must be programmed for the household and the water conditions. The contract should say who will set up the controller, verify the time and cycle settings, initiate any required cleaning or regeneration and check the system for leaks.
For equipment that regenerates or backwashes, ask what information will determine the programmed frequency or capacity. For cartridge systems, ask which cartridge will be installed at startup. For ultraviolet equipment, ask whether the installer will verify the alarm and monitoring functions.
Request a written record of the final settings at completion. These values provide a useful baseline if water quality changes or the system begins using more salt or water than expected.
Separate included supplies from future consumables
A contract may include the equipment but leave routine supplies to the homeowner. Identify which consumables are provided at installation and which must be purchased later. Depending on the system, these might include salt, filter cartridges, membranes, ultraviolet lamps, cleaning products or test supplies.
Ask for the exact replacement specification, not only a general description. The paperwork should also say whether using a compatible third-party consumable affects any warranty term. If the company requires a particular service schedule or branded replacement part, you should know that before buying the system.
Make conflicting documents follow a clear order
Water treatment sales often involve a proposal, test report, product brochure, financing form and final contract. Those documents may not use the same descriptions. The contract should identify which documents are part of the agreement and which one controls if their terms conflict.
Do not assume that a brochure shown during the appointment becomes part of the deal. If a diagram, specification sheet or written answer matters to your decision, ask for it to be attached and referenced in the signed contract.
Review model numbers, tank sizes and included options across every document. If the proposal identifies one system and the financing paperwork identifies another, have the discrepancy corrected before signing.
Use the schedule during installation and final walkthrough
Keep a copy of the signed equipment schedule available on installation day. Before equipment is connected, compare visible model labels and component counts with the paperwork. Ask about any substitution before it becomes difficult to reverse.
During the final walkthrough, locate each item on the schedule. Confirm that bypass valves move properly, drains are secured, supplied faucets or sensors are present and the promised fixtures receive treated water. Photograph model and serial labels where they are accessible.
Ask the installer to note approved changes directly on the completion paperwork. A verbal explanation may be forgotten, while a written record helps with future warranty claims, maintenance and service calls.
A short checklist before signing
A usable equipment schedule should let you answer these questions:
- What exact equipment am I buying?
- What tested issue or household goal does each component address?
- What media, cartridges or other treatment materials are included?
- What capacity and flow figures apply, and what do those figures mean?
- Which fixtures and water lines will receive treatment?
- What accessories, controls and safety devices are included?
- What startup work and programming will the installer perform?
- Which supplies will I need to purchase later?
- What substitutions are allowed?
- Which document controls if the paperwork conflicts?
If the contract cannot answer these questions, ask for a revised equipment schedule before committing. Clear identification makes proposals easier to compare, gives the installer a precise scope and gives you a practical way to confirm that the completed system is the one you agreed to purchase.