Before the installer arrives
Three things decide where the purifier can go, and they are easier to settle before someone is holding a drill.
Water in. A cold water line with its own isolating tap, so the purifier can be shut off without shutting the kitchen. If the supply comes from an overhead tank, the pressure will be low and the pump will do the work; that is normal, and it is the reason the pump exists. The feed should be tested once for TDS before anything is chosen, because the feed reading decides which membrane the machine needs; the TDS reference page explains what the number means.
Water out. A drain within reach of the reject line. The purifier sends two to three litres to drain for every litre it makes, every day, and the reject line has to go somewhere that will take it without backing up.
Power. A socket for the adapter, out of reach of splashes, and close enough that the low-voltage lead reaches without an extension.
The checklist
| Item | Correct | Wrong, and why it matters |
|---|---|---|
| Inlet tap | A dedicated isolating tap on the cold line, reachable without moving the machine | Tee'd off with no tap: every cartridge change means shutting the kitchen supply |
| Pre-filter bowl | Mounted upright, bowl down, with room below to swing the spanner and drop the cartridge out | Tight against a wall or a shelf: the bowl cannot be unscrewed without unmounting it |
| Pipe runs | Quarter-inch tube cut square, pushed fully home into each collar, no kinks, no tight bends | An angled cut or a half-inserted tube seals today and weeps under pump pressure next month |
| Drain line | To a drain or standpipe with an air gap above the water, falling all the way | Pushed below the water in a sink trap: backflow into the reject side and a smell in the cabinet |
| Mounting | On a wall that holds the machine full of water, level, with the cover removable | On a hollow partition or a tile that cracks; leaning against the wall on a counter |
| Adapter | 24 V DC, rated above the pump's draw, mounted dry and above any possible drip | On the cabinet floor under the housings, where the first leak finds it |
| Membrane and cartridges | Membrane the right GPD for the pump and the feed, cartridges the right fit for the housings, all dated | A 100 GPD membrane on a small pump, or a cartridge that looks right and does not seal |
| First flush | First tankful or two run to drain to clear carbon fines and preservative from the membrane | Drunk straight away: black specks and an odd taste blamed on the machine |
The pre-filter bowl, in detail
The wall-mounted bowl ahead of the purifier is where installs most often go wrong, because it is the part the installer did not bring. If the purifier has none, or the existing bowl is cracked or its thread stripped, both LUXGEN kits arrive complete with elbows, pipe and spanner and connect to quarter-inch push-fit tubing. The PFH-10 at ₹499 is the threaded-cap bowl with a 9-inch candle; the PFK-2C at ₹899 is the plain-cap bowl with two 10-inch spun candles, the choice for silty water, and it is rated for feed up to 2000 ppm.
Mount it upright with the bowl hanging down and a hand's width of clear space below. Check the flow arrow on the cap points from the inlet towards the purifier; a bowl plumbed backwards filters from the inside out and loads in weeks. The housing sizes guide covers which cartridge the bowl takes afterwards.
Pump and membrane, matched
Ask which membrane went in and what the pump is rated for. An 80 GPD membrane runs on the ordinary pump in most purifiers; a 100 GPD membrane needs a pump built for it, such as the LUX-PUMP-100 at 140 PSI, or it makes less water than the 80 would. On feed above 2000 ppm the membrane should be the molded high-TDS type. The 80 vs 100 GPD guide and the booster pump guide explain the pairing; the point here is only that it was checked, not assumed.
Before the technician leaves
- Watch a full cycle. Pump runs, drain flows steadily, tank fills, pump stops. A pump that keeps running with a full tank, or a drain that runs with the pump off, is a fault to fix now.
- Feel every joint. Housings hand-tight plus a quarter turn, every push-fit dry. Then come back in an hour and feel them again.
- Take the day-one readings. Feed TDS and output TDS after the flush, written on the housing with the date. This is the number every later reading is compared with, and without it the meter cannot tell you when the membrane is done. The how to measure TDS guide shows the method and the RO output TDS guide what the ratio should be.
- Date the cartridges. Sediment, carbon, membrane, on the housing with a marker. The filter change schedule then works from real dates.
- Get the part names. Which fit of cartridge, which GPD of membrane, so the next order is right without opening anything. The fit guide explains what the names mean.
- Ask what is yours to do. Cartridge swaps and the TDS log are homeowner jobs; the pump and the electrics are not. The service vs DIY guide draws that line.
Twenty-four hours later, check the cabinet floor for water and the adapter for warmth. A dry floor and a cool adapter mean the install is done.
Questions
Where should the RO drain line go?
To a drain or standpipe with an air gap above the water level, falling all the way so nothing sits in the line. Never below the water in a sink trap: that risks backflow into the reject side and a smell in the cabinet. The purifier sends two to three litres to drain for every litre it makes.
What should I check after RO installation?
Watch one full cycle, feel every housing and push-fit for drips, take the feed and output TDS after the first flush and write them on the housing with the date, date every cartridge, and note the part names for the next order. Check the cabinet floor and the adapter again the next day.
Does an RO purifier need a pre-filter bowl?
On borewell, tanker or silty water, yes: the wall-mounted bowl takes the grit before it reaches the purifier's own sediment cartridge. LUXGEN's two kits, the threaded-cap PFH-10 with a 9-inch candle and the plain-cap PFK-2C with two 10-inch spun candles, come complete with elbows, pipe and spanner for quarter-inch tubing.