DIY Fleck 5600SXT Install: What You Need Before You Start

A Fleck 5600SXT is the valve on most "DIY water softener" systems sold online. Installing one is ordinary plumbing: cut into the main line, add a bypass, run a drain line and a brine line, then program the valve. This page lists what Pentair's own manuals require so you can decide if it's a weekend job or a call to a plumber, and so you can check a pro's work. Everything here comes from Pentair's 5600SXT manuals and Hillsborough County's permit pages; your system's manual is the final word.

Check your site first

Requirement	What Pentair's manuals say
Water pressure	20 to 125 psi. Below 20 psi the regeneration valve won't work well; above 125 psi you need a pressure regulator.
Temperature	Room between 34°F and 120°F. Water temperature limit is 100°F in the Pentair system manual and 110°F in the Fleck valve service manual. Never let it freeze.
Distance to water heater	At least 10 feet of pipe between the softener and the water heater, so hot water can't back up into the system.
Drain	A floor drain, standpipe, or tub as close as possible; ideally within 20 feet.
Power	A grounded outlet that is always on, not on a switch. The SXT keeps time for at least 8 hours in an outage.
Floor and access	Level, firm floor with room to service the valve and add salt.
Outdoors (common in Florida garages and side yards)	Pentair recommends indoors. The valve is rated NEMA 3, so falling rain is OK, but not constant mist, corrosive air, or sprinkler spray from below. Sun fades the plastic but Pentair says it won't cause failure.
Existing pipes	Replace piping heavily built up with lime or iron. If it's clogged with iron, put an iron filter ahead of the softener (see iron filter vs softener).

Parts and supplies checklist

Softener sized for your water. Get your hardness and iron numbers first (testing guide), then size the resin (sizing guide). Pentair's packaged 5600SXT systems come in 1, 1.5 and 2 cu ft tanks (9x48, 10x54, 12x52) with a 14 x 34 inch brine tank.
Bypass valve (usually included) and inlet/outlet adapters for your pipe. The valve takes 3/4" or 1" connections.
Drain line: 1/2" minimum rigid or semi-rigid. Use 3/4" if the run is over 20 feet or backwash flow is over 7 gpm.
Brine line: 3/8" semi-rigid tubing. Soft hose can collapse under the vacuum during brine draw.
Brine tank overflow tubing to a drain, on its own separate line.
Grounding strap across the inlet and outlet pipes, if your house plumbing is metal and grounded, since a plastic bypass breaks that path.
100% silicone grease for O-rings. No Vaseline or petroleum grease.
PTFE (plumber's) tape for NPT threads and the drain fitting. Pentair says not to use thread sealant paste.
Lead-free solder, if you sweat copper.
Salt: sodium chloride pellet salt. The Fleck manual says not to use granulated or rock salt (see salt types).

The rules people get wrong

Air gap at the drain. Never push the drain line into a drain pipe, sewer, or trap. Leave a gap so sewage can't be siphoned back. The Fleck manual says at least 2x the drain line diameter, minimum 1"; Pentair's European manual says 2 pipe diameters or 1.5", whichever is larger. Check your local code.
Drain line height. It can rise up to 6 feet if the run is 15 feet or less and pressure is at least 40 psi, plus 2 more feet per extra 10 psi.
Inlet vs outlet. Incoming water must go to the valve's inlet port. When replacing an old unit, the existing pipes are sometimes reversed.
Solder first, valve last. Do all house plumbing first and let soldered pipe cool before connecting the plastic valve. Keep solder joints at least 6" from the drain line flow control.
Hand-tighten plastic. No pliers or pipe wrenches on plastic fittings, and don't hang the system's weight on the valve or bypass.
Don't tip the resin tank. Turning it upside down or on its side can push resin into the valve.
Other equipment goes upstream. Sediment, iron, neutralizer, or carbon filters go before the softener.
Safe water only. The system isn't meant to treat water that's microbiologically unsafe without disinfection.

Start-up, step by step

Put about 1" of water in the brine tank above the grid plate (or to the top of the air check if there's no grid). No salt yet.
With the bypass in "bypass," turn the water on and run a nearby cold tap to flush out solder bits.
Rotate the bypass handles 2 to 3 times to seat the O-rings, then slowly move to "service" and let the tank fill. Run a cold tap to purge air.
Plug in the transformer and program the valve (below).
Hold Extra Cycle for 5 seconds to start a regeneration. In backwash, run until the drain water is clear (about 10 minutes).
Advance with Extra Cycle to brine draw and confirm it pulls water from the brine tank, then rapid rinse until clear (about 5 minutes), then brine refill.
Add salt.

Programming basics

Time of day (TD): hold Up or Down until "TD" shows.
User settings: hold Up and Down for 5 seconds to reach Day Override (DO), Regeneration Time (RT), Feed Water Hardness (H, 1 to 199), and Reserve (RC or SF).
Hardness: enter your real number in grains per gallon. Tampa's 2025 utility report averaged 12.3 gpg; add iron compensation if you have iron (see the sizing guide).
Capacity and salt: set in Master Programming. Pentair's manual says to contact a water dealer before changing it; your seller should give you the capacity and salt setting for your tank.
How metering works: the valve divides unit capacity by hardness, subtracts the reserve, and regenerates when that many gallons are used (or after the day override).

Permits in Hillsborough County

Hillsborough County's "work exempt from permits" list doesn't include adding a softener to the water line, so ask Building Services or check HillsGovHub before you cut pipe. If you live inside a city limit, that city's building department may handle the permit instead.
Homeowners can usually pull their own permit as an owner-builder under Florida Statute 489.103(7): the home must be deeded in your name and be your own residence, you must sign an Owner Builder Disclosure Statement, and you can't sell or rent it for one year after the work is done.
If you hire someone, Florida requires a licensed contractor, and the contractor pulls the permit.

DIY or hire it out?

DIY is reasonable if: you already sweat copper or use PEX/push fittings confidently, there's a drain and outlet nearby, and your main line is easy to reach.
Get a pro if: the main line is hard to reach or in a slab, there's no drain within reach, you have iron or sulfur that needs an extra filter, or you'd rather the installer own the permit and warranty.
Either way, compare an itemized quote with the parts list above (see quotes decoded and Clack vs Fleck).

Coming soon: links to DIY Fleck 5600SXT systems, bypass kits and install parts.

Sources

Rather not DIY? Get itemized quotes from local Tampa Bay installers →