Water purifier not working? Safe checks before you call a technician

Before you book a visit, spend ten minutes on the checks below. A good share of "my RO has stopped" calls turn out to be an empty overhead tank, a closed inlet tap, a tripped socket, or a tube that slipped out of a push-fit joint — all things you can see and fix without tools. The rest of the time the checks tell you which fault to book, and the technician arrives with the right parts. One rule first: the purifier mixes water and electricity in a damp cabinet, so switch off at the socket before you touch any fitting.

Check one: power

• Is the indicator light on? If not, is the plug firmly in and is the socket live (test it with a phone charger)?
• Is the MCB for the kitchen circuit on?
• Is the adapter warm and silent, or silent and cold? Cold and dead usually means the adapter has failed. Do not open it; note it for the booking.

If the light is on but nothing happens, move to water.

Check two: water in, water out

• Open the kitchen tap. If the mains or overhead tank is empty, the purifier cannot fill. This is the single most common cause of "not filling" in Nellore summers when the tank runs dry by evening.
• Find the small inlet valve on the supply line (often a quarter-turn tap on the pipe behind the unit). Is it open? Someone cleaning under the sink may have nudged it.
• Is the reject line running? A steady stream into the drain while the unit fills is normal. No reject at all with the pump running means the water is not getting in; reject running constantly with the tank full means a valve is not shutting.
• Is any tube kinked or pinched against the wall?

Check three: the tank and the tap

• Empty the tank fully by leaving the tap open until it stops. If the flow was weak from a full tank but strong at first, the tank's air bladder has probably lost its charge; note that, it is a quick job for a technician.
• Look at the dispensing tap. A worn washer drips; a slimy feel inside the spout is a hygiene issue, not a fault — clean it with a small brush.
• If the unit has a transparent sediment housing, look at the candle. Brown or grey means it is due, and low flow is the reason you are here.

Check four: leaks

Switch off at the socket. Dry every fitting and the base with a cloth. Switch on, let it run, and watch. The first drop tells you where.

• A push-fit joint weeping: press the tube in firmly and straight until it stops. Most weep because the tube was pulled slightly at an angle.
• A housing weeping at the seam: tighten by hand, evenly. Do not use a wrench; over-tightening cracks housings.
• Water from the tank area: the float valve. That is a visit.
• Water only on the outside of a cold tank in a humid kitchen: condensation, not a leak. A towel underneath in the monsoon is the fix.

Check five: taste and smell

Run two full tanks out and taste a fresh glass. If the off taste is gone, it was stale water. If it stays, note whether it is flat, chemical, earthy or rotten-egg — those point to carbon filters, chlorine in the source, tank film, or a borewell sulphur problem respectively, and the distinction helps the technician.

If you have a TDS meter, measure a fresh glass. A number far above what you usually see points to the membrane or a TDS controller set too high.

What you should not do

• Do not open the adapter, the pump, or the UV chamber. The UV lamp runs on a high-voltage ballast, and the light damages eyes and skin.
• Do not bypass the float switch or the pressure switch to force filling. They protect the pump.
• Do not pour bleach, vinegar or detergent through the unit to "clean" it. Carbon and membranes do not recover from that.
• Do not run the unit with the inlet closed to "test the pump". Pumps run dry are damaged quickly.
• Do not touch anything with wet hands while the unit is live. Socket off first, every time.

What to book, based on what you found

What you found	Book
Power and water fine, flow weak, filters old	Filter change — ₹299
Filters recent, flow still weak, pump hums	Low water flow — ₹350
A drip you cannot stop by hand	Leaking — ₹350
Taste or smell that two tanks do not clear	Foul taste / smell — ₹299
Light on, water present, nothing fills	Low water flow — ₹350 (pump and valve check)
No light at all, socket tested live	Water purifier service — ₹299; say "no power to unit" in the note

Parts that turn out to be needed — a filter, membrane, adapter, float valve — are charged at MRP and shown to you before fitting, and you can say no. Tell the technician what you checked; it shortens the diagnosis and sometimes the bill.