How to Fix Aquaguard Water Purifier LPS Error (No Input Water)

What error LPS means

The LPS Error means the Low Pressure Switch has not sensed inlet water, so the purifier has shut the pump down to prevent it running dry. On the 3-LED models — Astor, Delight NXT and Sure Delight NXT — the blue Power LED blinks at a 0.25-second rate. On the Under-The-Counter (UTC) range the LED goes solid purple instead. In most homes the cause is upstream of the appliance, which makes this one of the few Aquaguard alerts you can genuinely clear yourself.

Why error LPS happens on a Aquaguard Water Purifier

On a Aquaguard Water Purifier, error LPStypically resolves to one of three root-cause categories. They’re ordered cheapest-to-verify first — start at the top and only escalate if the first cause is ruled out.

• Mechanical: blockage, obstruction, or worn moving part. A common cause across Aquaguard Water Purifiers in India — sediment and carbon filters load up and membranes foul with use. Our step-by-step fix below targets this category first because it’s the cheapest to verify and resolvereports.
• Electrical: voltage spike, sensor fault, or PCB anomaly. India’s grid carries more voltage fluctuation than many appliance design tolerances assume, and a routine surge or sag can be enough to throw LPS. If you’ve had recent voltage events (lights flickering, AC tripping), start your investigation here. A working stabilizer prevents this entire category.
• Software / configuration: stuck child-lock, demo-mode, or pending firmware reset.Less common but the cheapest fix when it applies — a 60-second factory reset clears it. We list this last because it’s rarely the actual cause, but check it before disassembling anything.

Safety first

Step-by-step fix

1. 1

   Step 1

   Confirm the indicator matches the LPS Error for your model

   On the 3-LED models — Astor, Delight NXT and Sure Delight NXT — the LPS Error blinks the blue Power LED at a 0.25-second rate, a fast flicker rather than a slow flash. On the Under-The-Counter (UTC) range the same fault shows the LED solid purple instead. If your panel is showing a red Service LED rather than a blue or purple one, you are looking at a different fault.

   Pro tip: The UTC units sit inside a cabinet, so the LED is easy to miss. Open the cabinet door before you conclude the purifier is simply dead.

2. 2

   Step 2

   Work back up the supply chain

   Start furthest away and work in. Is the municipal supply running right now? Does the overhead tank still have water in it — check the level, not just the pump timer? Is the inlet tap that feeds the purifier fully open, including any isolation valve fitted under the sink on UTC installs? Open another tap on the same line to confirm water is actually arriving at that point in the house.

   Pro tip: On timed municipal supply, note whether the error appears at the same hour each day. That pattern alone identifies a supply-window problem rather than an appliance problem.

3. 3

   Step 3

   Check the inlet pressure against the 0.3 kg/cm² minimum

   Eureka Forbes specifies a minimum inlet pressure of 0.3 kg per square centimetre. If your feed is gravity-only from a tank sitting barely above counter height, you may simply be below spec — which is a plumbing problem, not a purifier fault. A dial pressure gauge screwed onto the inlet tap gives a definitive reading; without one, a weak, non-forceful stream from the tap that feeds the purifier is a strong hint.

   Caution: Switch the purifier off at the wall before fitting or removing a gauge on the inlet tap.

4. 4

   Step 4

   Clean or replace the pre-filter on the inlet line

   A clogged i-Filter or sediment pre-filter starves the low pressure switch even when house pressure is fine, and it is the single most common cause after supply itself. If your model has the external pre-filter housing fitted on the inlet line, close the inlet tap, unscrew the housing with a bucket underneath, and inspect the candle. Silt-brown or slimy means replace it rather than rinse it.

   Pro tip: In silty monsoon supply, pre-filters in eastern and north-eastern India can clog inside a few weeks. If you are clearing this error every monsoon, budget for a mid-season pre-filter change.

5. 5

   Step 5

   Trace the inlet tube for kinks and crushes

   Follow the inlet tube along its whole run, from the tap to the purifier's inlet port. A tube pinched behind the unit when it was pushed back against the wall, crushed under a cabinet foot, or bent tight around a corner will throttle flow enough to trip the LPS. Ease out any tight bend and re-route the tube with a gentle sweep instead of a sharp corner.

   Pro tip: Leave a hand's width of clearance behind the purifier permanently. Most crushed tubes are created the day someone tidies the kitchen.

6. 6

   Step 6

   Restore supply and watch the indicator

   With the inlet tap fully open and water confirmed at the tap, switch the purifier back on at the wall and watch the panel. Once the low pressure switch senses inlet water again, the blinking blue Power LED or solid purple UTC LED should clear and the unit should resume normally. Give it a full start-up cycle before deciding it has not worked.

   Pro tip: If it clears and then returns within the hour, treat it as a pressure or pre-filter problem rather than a supply outage, and go back to Steps 3 and 4.

7. 7

   Step 7

   If it persists with confirmed water and pressure, stop and book a visit

   Supply confirmed, pressure at or above 0.3 kg/cm², a clean pre-filter and an unkinked tube — and the error is still showing? That points at the low pressure switch itself having failed or stuck, or at a loose LPS connector on the main PCB. Both are inside the sealed mains enclosure and belong to an authorised Eureka Forbes technician.

   Caution: Do not remove or bypass the switch to prove the point. It is the only protection your booster pump has against dry running.

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Common mistakes Aquaguard Water Purifier owners make with error LPS

These six anti-patterns turn a routine 30-minute fix into a costly repair or warranty void. Read before starting.

• Forcing a stuck door, lid, or panel. Prising open a Aquaguard Water Purifier housing while it is in a fault state. Forcing it usually breaks the latch or sensor — turning a small part replacement into a full service call. If the door won’t open, run the safety-disconnect step first, then try again.
• Repeated unplug-and-replug as a “reset” ritual. Cycling power three or four times without diagnosing the underlying cause stresses the PCB and can convert a soft fault into a permanent firmware-corruption code. Reset once, observe whether the error returns immediately, then move to actual diagnosis if it does.
• Pouring water (or any liquid) into electronics-adjacent areas to flush a blockage.Even a small amount near the PCB or main wiring harness can cause permanent damage that voids warranty. The unit’s drainage paths exist for a reason; if a blockage isn’t cleared by the manual procedure, it isn’t getting cleared by improvisation either.
• Skipping the safety-disconnect step.“I’ll just check quickly” is the most expensive sentence in appliance repair. Working live on a 230V circuit (especially with a hot or wet appliance) carries real shock risk and instantly voids any warranty claim. Disconnect, wait two minutes for capacitor drain, then proceed.
• Buying counterfeit replacement parts on Amazon.in. Red flags: price below 60% of Aquaguard authorised price, generic packaging without a model-compatibility list, seller name that doesn’t match a known Aquaguard parts distributor, listings dated within the last 30 days with no reviews. Counterfeit parts often work for 2-3 weeks then fail with a different error, costing you double.
• Calling an “independent” technician for a warranty-covered unit. Indian appliances under Aquaguard warranty must be serviced by authorised technicians or the warranty voids permanently. Even if the warranty is expired, third-party local technicians often replace working parts to inflate the bill — verify each part swap by asking to see the failure on the old part before they install the new one.

Preventing future LPS on your Aquaguard Water Purifier

The fix above resolves the current instance. These five maintenance habits prevent it from coming back, specific to Aquaguard Water Purifiers in Indian operating conditions (hard water, voltage variability, monsoon humidity).

• Monthly: check filter life and flush the sediment pre-filter. Hard-water deposits and everyday debris are a frequent cause of recurring LPS in India, and a few minutes each month is the cheapest way to avoid a repeat.
• Quarterly: descale water-touching components. Use food-grade citric acid or a Aquaguard approved descaler for hard-water regions (Bangalore, Hyderabad, large parts of Maharashtra and Tamil Nadu). Skipping this in a hard-water zone shortens the life of the heating and water-touching parts.
• Run the unit through a working stabilizer. A mainline stabilizer sized for Water Purifiers is the cheapest protection against voltage-induced LPS occurrences. The MCB on your distribution board is not a substitute — it trips on overload, not on under-voltage or surge.
• Decide AMC vs DIY honestly. Compare the AquaguardAMC quote against what you have actually spent on service. If your unit is >5 years old and you’ve had two service calls in the last 18 months, an AMC usually pays for itself. Younger units with no service history: DIY plus stabilizer is cheaper.
• Watch monthly for early-warning signs. Unusual noise during a specific cycle phase, water spotting, mild burning smell — any of these means a service call within a week, not a wait-and-see month. Catching LPS-precursor symptoms early turns a major repair into a routine maintenance visit.

If error LPS returns within 30 days of completing the fix above, escalate directly to Aquaguardauthorised service — repeat patterns within a month indicate a deeper fault (worn bearing, failing PCB, leak that wasn’t fully identified) that surface-level repair won’t resolve. Document the dates and circumstances of each occurrence; the service centre will use this to prioritize root-cause investigation.