Printers & Peripherals
UPS Repair in Dhaka: How to Keep Your Backup Power Running Through Load-Shedding Season
12 June 2026 · 15 min read · BAYAS Editorial
If you live in Dhaka, you already know the sound: the click of a relay, the ceiling fan slowing to a stop, and then — if you are lucky — the steady hum of your UPS kicking in before your PC screen goes dark. When that hum does not come, you have a problem. UPS repair in Dhaka is not a luxury service; it is the thin line between a clean shutdown and a corrupted hard drive, a lost hour of work, or a fried power supply.
At BAYAS, we service offline, line-interactive, and online UPS units across 36 Dhaka zones — from 650 VA desktop backups in Mirpur apartments to 6 kVA online towers powering office server rooms in Motijheel. Our technicians see the same failure patterns repeat every load-shedding season. This guide explains what goes wrong, what you can check yourself, and when to call a professional.
Why UPS units fail faster in Dhaka than anywhere else
A UPS is a simple machine: battery, charger circuit, inverter, and transfer relay. But Dhaka's electrical environment punishes every one of those components harder than the manufacturer ever designed for.
Load-shedding frequency. In peak summer months, some Dhaka zones experience 6 to 12 power cuts per day. A UPS that switches to battery 300 times a month ages three times faster than one cycling 100 times. The relay contacts wear. The battery never fully recharges between cuts. The inverter MOSFETs run hot for hours at a stretch.
Voltage instability. Even when the grid is "on," Dhaka line voltage can swing from 160V to 280V. Offline and line-interactive UPS units pass this dirty power straight through on mains mode, and the AVR (automatic voltage regulation) transformer inside the UPS takes the hit. We replace burned AVR transformers in Mercury and Power Guard units at our Uttarkhan workshop nearly every week during summer.
Heat and humidity. Sealed lead-acid (SLA) batteries have a rated lifespan of 3 to 5 years at 25°C. At 35°C — a typical June afternoon in a non-AC Dhaka room — that lifespan halves. Humidity above 70% causes PCB corrosion on charger circuits and oxide bridges between MOSFET gate pins. What started as a BDT 1,200 battery swap becomes a BDT 4,000 board repair because moisture sat on the PCB for six months.
Cheap replacement batteries. The most common repair we undo at BAYAS is a "new" battery that failed in four months. Dhaka shops routinely sell recycled SLA cells, repainted and relabeled, for BDT 800 to BDT 1,500. They weigh less, they hold half the rated capacity, and they sulfate internally within weeks. We will come back to this.
Common UPS faults our technicians see every week in Dhaka
Across hundreds of UPS service visits, these five problems account for over 80% of the calls we receive.
1. UPS beeps and shuts down immediately during load-shedding
What it means: The battery cannot hold enough charge to sustain the connected load. This is either a dead battery, a battery that was undersized for the load, or a charger circuit that stopped charging weeks ago and you only noticed when the power cut.
What to check: Note the beep pattern. Most UPS units use a specific sequence — continuous short beeps usually mean overload, while a beep every 2 to 4 seconds means battery mode with a low battery warning. If the UPS beeps and shuts down within 30 seconds with a known-good battery, the inverter board may have a failed MOSFET or transformer.
2. UPS shows mains power but battery never charges
What it means: The charger PCB — usually a small daughterboard inside the UPS — has failed. This board converts 220V AC to the ~13.8V DC needed to float-charge a 12V SLA battery. Common failure points: the bridge rectifier, the charging MOSFET, or the thermistor that regulates charge current.
Why it matters: Your UPS runs perfectly on mains but the moment load-shedding hits, you get zero backup — even with a brand new battery. This fault often goes unnoticed for weeks because the UPS sits silently on mains. We recommend a monthly self-test: turn off the wall switch with your PC and monitor connected and see if the UPS holds for at least 2 minutes.
3. UPS runs hot and smells like burning plastic
What it means: Overheating — either the cooling fan has failed, the inverter is overloaded, or dried electrolytic capacitors on the main board have increased internal resistance and are cooking themselves.
BAYAS observation: We see this most often in online (double-conversion) UPS units that run the inverter 24/7. In a Dhaka office without air conditioning, ambient temperatures regularly exceed 35°C, and the UPS's internal fan — typically a cheap 40mm or 80mm sleeve-bearing unit — seizes within 12 to 18 months. A BDT 300 fan replacement prevents a BDT 8,000 inverter board replacement. We stock 40mm, 80mm, and 120mm UPS-grade fans at our workshop for this exact reason.
4. Battery swells or leaks within a year of replacement
What it means: Counterfeit battery. Genuine 12V 7Ah or 9Ah SLA batteries from brands like Rahimafrooz, Lucas, or Leoch last 2 to 3 years in Dhaka conditions. If yours is bulging, leaking white sulfate powder, or cracked at the seam within 12 months, the cell was almost certainly a recycled unit.
How to verify: A genuine 12V 7Ah SLA battery weighs 2.1 to 2.4 kg. Recycled cells typically weigh 1.6 to 1.9 kg because they contain less lead. At BAYAS, every replacement battery comes with the retail invoice in your name — supplier, date, brand, and weight. No invoice, no warranty claim later.
5. UPS clicks repeatedly (rapid relay chatter) during load-shedding
What it means: The transfer relay is oscillating — switching between mains and battery faster than the connected equipment can tolerate. This is often caused by a borderline-low battery voltage that triggers the low-battery cutoff, then recovers voltage when the load drops, triggering reconnection, and so on. Other causes: a failing relay driver transistor or a mains sensing circuit that incorrectly detects "mains restored."
Risk: Relay chatter sends voltage spikes into your PC's power supply. We have seen desktops with blown PSUs because a chattering UPS was left connected for a full load-shedding session. If you hear rapid clicking, shut down the PC and unplug the UPS immediately.
Quick DIY checks before you call a UPS technician
Before you pay for a home service visit, run these four checks. You might save yourself the call-out fee entirely — or at least give the technician useful information before they arrive.
1. The kettle test. Plug a table lamp or an electric kettle into the wall socket your UPS uses. If the appliance works, the wall socket is fine and the problem is in the UPS or its input fuse. If the socket is dead, check your distribution board — the circuit breaker for that room may have tripped.
2. The battery disconnect test. Unplug the UPS battery connector (a red-and-black spade terminal pair inside the battery compartment), wait 30 seconds, and reconnect it. Sometimes a UPS controller board locks into a fault state and needs a hard reset. This fixes roughly 1 in 8 "dead" UPS units we see — not a guaranteed cure, but worth trying.
3. The no-load startup test. Disconnect all equipment from the UPS output sockets. Turn on the UPS with nothing connected. If it starts and stays on (with the battery connected), add devices one at a time — monitor first, then the desktop. If the UPS shuts down when a specific device is added, that device may have a shorted power supply drawing excessive startup current.
4. The battery voltage check. If you own or can borrow a multimeter, measure the DC voltage across the battery terminals. A healthy 12V SLA battery reads 12.6V to 13.2V at rest. Below 10.5V means the battery is deeply discharged and may be permanently damaged. Below 8V means the battery is dead — replace it. If the voltage reads 0V, either the battery's internal fuse link has blown or the terminals are severely corroded.
⚠️ Safety note: UPS units contain capacitors that hold dangerous charge even when unplugged. Do not touch any exposed PCB, heatsink, or transformer winding. If you are not comfortable working with electrical equipment, skip the multimeter test and call a technician.
What professional UPS repair actually involves
When a BAYAS technician arrives for a UPS repair in Dhaka, the process follows a structured diagnostic ladder — not guesswork.
Step 1: Load test with a known-good battery. We disconnect the internal battery and connect a calibrated test battery of known capacity. If the UPS runs normally on the test battery, the fault is the battery — a straightforward swap with a genuine replacement unit and invoice.
Step 2: Battery health measurement. We use a battery impedance tester to measure the internal resistance of your existing battery. A healthy 12V 7Ah SLA battery has an internal resistance below 25 milliohms. Above 50 milliohms means significant sulfation. Above 100 milliohms means the battery is end-of-life regardless of its voltage reading.
Step 3: Charger voltage check. With the UPS on mains, we measure the DC voltage at the battery terminals. It should read 13.5V to 13.8V (float charge). Below 13V means the charger circuit is faulty — the root cause of many "battery died in six months" complaints.
Step 4: Inverter waveform inspection. For line-interactive and online UPS units, we connect an oscilloscope to the output and verify the inverter produces a proper sine wave or stepped approximation. A distorted waveform can cause PC power supplies to buzz, reboot, or refuse to start. This is particularly important for online UPS units powering servers or networking equipment.
Step 5: Board-level repair. If the charger PCB or inverter board has failed, we repair it at the component level at our Uttarkhan workshop. This includes: MOSFET replacement, capacitor replacement (bulging or dried electrolytics), relay replacement, thermistor replacement, and transformer rewinding when viable. We quote a repair ceiling before opening the board — if the fix exceeds the ceiling, we recommend replacement instead.
Step 6: Load test before handover. Every repaired UPS runs a 15-minute real-load test (a desktop PC and monitor, or equivalent resistive load) before we pack up. You see the UPS hold the load before you pay.
UPS repair cost in Dhaka (2026)
Pricing varies by UPS type, brand, and the specific fault. These are the ranges we quote based on hundreds of UPS repairs across Dhaka.
| Service | Parts cost | Labor at BAYAS | Total range |
|---|---|---|---|
| Battery replacement (12V 7Ah genuine) | BDT 1,400 – 2,200 | BDT 500 | BDT 1,900 – 2,700 |
| Battery replacement (12V 9Ah genuine) | BDT 1,800 – 2,800 | BDT 500 | BDT 2,300 – 3,300 |
| Dual-battery UPS (2× 12V 7Ah or 9Ah) | BDT 2,800 – 5,600 | BDT 800 | BDT 3,600 – 6,400 |
| Fan replacement (40mm or 80mm) | BDT 300 – 600 | BDT 500 | BDT 800 – 1,100 |
| Charger PCB repair (component-level) | BDT 500 – 2,000 | BDT 1,500 – 2,500 | BDT 2,000 – 4,500 |
| Inverter board repair (MOSFET/cap/relay) | BDT 800 – 3,000 | BDT 2,000 – 3,500 | BDT 2,800 – 6,500 |
| Full online UPS service + battery set | BDT 5,000 – 15,000+ | BDT 3,000 – 5,000 | BDT 8,000 – 20,000+ |
| Home visit + diagnosis (credited to repair) | — | BDT 700 – 1,200 | BDT 700 – 1,200 |
A note on brands: APC by Schneider and Eaton UPS units use proprietary battery packs in some models (Back-UPS Pro series, for example). These packs cost more — typically BDT 3,500 to BDT 7,000 — but APC does not sell individual cells. Mercury, Power Guard, and Power Tree use standard 12V SLA batteries that are widely available at Dhaka electronics retailers like StarTech and Ryans. We source from these suppliers and hand you the invoice directly.
How to make your UPS last longer in Bangladesh conditions
A UPS is not a set-and-forget device — especially not in Dhaka. A few habits can extend its life by two to three years.
Run a monthly self-test. Once a month, unplug the UPS from the wall with your equipment connected and let it run on battery for 2 to 3 minutes. This exercises the battery, verifies the inverter is functional, and reveals problems before an actual power cut does.
Keep the UPS in a ventilated area. The #1 cause of premature failure we see is a UPS stuffed behind a desk, under a pile of papers, or wedged into a cabinet with zero airflow. The battery and inverter need at least 6 inches of clearance on all sides. If the UPS exterior feels warm to the touch when running on mains, it needs better ventilation.
Replace the battery every 2 years — not when it dies. In Dhaka's heat, an SLA battery's capacity degrades to roughly 60% after 24 months. You may still get 2 to 5 minutes of backup, which feels "working," but under real load it may drop to 30 seconds and cause a hard shutdown. Preemptive replacement every 2 years costs BDT 1,900 to BDT 3,300 — far less than a desktop repair for a blown PSU or corrupted drive.
Use a voltage stabilizer upstream if your zone has severe voltage swings. Some older parts of Old Dhaka, Jatrabari, and Keraniganj experience voltage dips below 140V. A line-interactive UPS's AVR can only boost voltage by a limited range. A dedicated stabilizer before the UPS protects both the UPS and the connected equipment.
Avoid daisy-chaining extension cords. A UPS plugged into a BDT 150 multi-plug that is itself plugged into a BDT 150 multi-plug creates high-resistance connections that generate heat, drop voltage, and can arc under load. Plug the UPS directly into the wall socket. If you must use an extension, use a heavy-duty 16A-rated cord — not the thin white ones sold at footpath stalls.
When to repair vs. when to replace
A rough rule we use at BAYAS: if the repair cost exceeds 60% of a comparable new unit, replacement is usually the better financial decision.
| UPS type | New unit cost (Dhaka) | Repair tipping point |
|---|---|---|
| 650 VA offline (Mercury, Power Guard) | BDT 2,500 – 4,000 | Repair above BDT 1,500 – 2,400 |
| 1200 VA line-interactive (APC, Mercury) | BDT 5,000 – 9,000 | Repair above BDT 3,000 – 5,400 |
| 1500 VA–2000 VA line-interactive | BDT 9,000 – 18,000 | Repair above BDT 5,400 – 10,800 |
| 3 kVA–6 kVA online (Eaton, APC, Power Tree) | BDT 35,000 – 80,000+ | Board repair almost always worthwhile |
But there is a nuance: a BDT 4,000 Mercury 650 VA unit with a dead battery is a BDT 1,900 fix that gives you another 18 to 24 months of service — clearly worth it. The same unit with a burned inverter board and a dead charger is a BDT 4,500 to BDT 5,000 repair, which exceeds the cost of a new unit. We tell you honestly which side of the line you are on.
Get a UPS repair quote for your Dhaka location
Every UPS model has its own battery size, PCB layout, and failure pattern. The pricing ranges above cover the most common repairs, but your exact quote depends on your brand, VA rating, and the specific fault.
WhatsApp BAYAS at 01712-644590 with:
- UPS brand and model (e.g., "APC Back-UPS 1100VA" or "Mercury 650VA Elite")
- The symptom (e.g., "beeps and shuts down in 10 seconds" or "never charges the battery")
- A photo of the UPS label (showing the model number and electrical ratings)
- Your Dhaka zone
We reply with a specific quote within minutes during business hours (8 AM to 11 PM, 7 days). Our technician brings the right battery and common PCB components on the first visit so most repairs are completed same-day. No charge for the quote. No obligation.
If your UPS is part of a larger office setup — multiple units, server racks, or networking equipment — ask about our annual maintenance contracts for businesses. We offer monthly preventive checks, battery health tracking, and priority response during load-shedding season across commercial Dhaka zones.
This guide was written by BAYAS Editorial, based on UPS repair data collected by our technicians across 36 Dhaka zones since 2018. Prices reflect the Dhaka retail market as of June 2026 and may vary with battery availability and brand-specific part costs. Last updated: June 12, 2026.