Online DIY water system or professional installation

Price is a fair reason to look at a system you can order online. The way to compare it is to put the same things on both sides: sizing, the installation, permits and paperwork, the warranty, and who you call when something needs attention. This page walks through each one. We do not compare prices here.

Sizing: what the box does not know about your house

• Flow. Every filter adds some resistance, and sizing the system to your home's flow rate is how water pressure is protected. Each system has a maximum flow. The Nuvia Sentry is listed at up to 40 gallons per minute and the Nuvia Filtro at up to 28. Ask for the number in writing for any system you consider, and compare it with your home's demand.
• Chlorine is not chloramine. Water agencies disinfect with one or the other. Chloramine is harder to remove. It takes catalytic carbon, made for the job, and enough contact time with the water. A tank sized for chlorine is not the same as a system for chloramine. See whole-house water filtration for the detail, and ask which carbon is in any system.
• Your own water. Your agency publishes a hardness number each year, and every city page shows it. The number on your tap can differ, which is what the free water analysis is for.

Plumbing and permits

A whole-house system is installed on the main water line where water enters your home. That is a connection into your plumbing, and it is where the permit question starts.

The state board that licenses contractors draws a line in its own definitions. A C-55 water conditioning contractor installs water conditioning equipment with only the pipe and fittings needed to connect it to the water supply and to bypass the parts of the supply that should not get conditioned water. The plumbing classification, C-36, covers water piping from the property owner's side of the meter to the structure. The state board's Hire a Licensed Contractor page has guides on what type of contractor a project needs, whether it needs a building permit, and an owner-builder note.

Softeners carry extra rules

California sets equipment rules for a residential softener that sends brine to the sewer, and they apply to a unit you order online as much as to one a contractor installs:

• It has to regenerate only when needed. A softener on a clock timer cannot be installed in California.
• It has to carry a third-party certified salt-efficiency rating.
• Water-saving devices go in at the same time.
• A contractor with a C-55 or C-36 license certifies the installation, and the certification is filed with the local plumbing-permit agency.

On top of that, some cities and sewer agencies bar new salt-based installs or require a permit. Nothing in the box checks your address against those rules, so you have to. The California softener rules page lists what we found city by city. If your city bars the salt-based kind, exchange-tank service and salt-free systems are the other routes.

Warranty and who stands behind it

Warranties differ on who has to install the system. Nuvia's warranty applies when an authorized Nuvia dealer installs the system and it is registered online, and it lists installs by anyone else as not covered. Read the warranty on any system, ours or anyone else's, for three things: who has to install it, whether you have to register it, and what voids it.

You can also check the license of any contractor you hire. Nuvia's license and insurance page shows the state's record for ours and walks through checking any contractor.

Questions to ask before you buy any system

1. What is its maximum flow in gallons per minute? Get it in writing.
2. For chloramine, which carbon is in it? Ask for the type in writing.
3. For a softener, does it regenerate on demand and carry a certified salt-efficiency rating?
4. Is it allowed at my address? Ask your city or sewer agency.
5. Who pulls the permit and who signs the contractor's certification?
6. Is the certification listed for the exact model number? "Tested to" a standard is not the same as certified. Check the certifier's own listing, such as NSF or IAPMO R&T.
7. What does the warranty require and what voids it?
8. Who do I call when it needs attention?

When a do-it-yourself system can make sense

If your city's rules need no permit or contractor paperwork for the equipment, the sizing is in writing, the certification is listed for the exact model, and you are comfortable making the plumbing connection yourself, a do-it-yourself system is a fair choice. We would rather you work through the list above than skip it.

Start with the free water analysis

Whichever way you go, start with your own numbers. The free water analysis is done at your tap. It looks at hardness, chlorine and total dissolved solids, and it is not a health screening. You see the numbers first, then you pick a system that fits them.