Whole-House Dehumidification System
Efficiently Dehumidifies Multiple Spaces Simultaneously.
UTC20 · 55 · 68 · 120
Product Overview
Technical specs & features
View specs
Before you buy · Q&A
Good to Know
Whole-house setups, running cost vs aircon, windows, bathrooms, humidity targets — the questions everyone asks before installing.
Read the answers
7 chapters · official
User Manual
Safety, product overview, control panel, operation, app, maintenance, warranty.
Open manual
7 steps · most read
Installation
Prep, hanging, drainage, ducting, controls, power, commissioning.
Open guide
Real installs · case studies
Project Showcase
Residential, commercial, storage, cellar — project photos and notes from completed installs.
View cases
🇸🇬 Singapore
DBA Electric Pte. Ltd.
Block B, Cititech Industrial Building, 629 Aljunied Road, #07‑08, Singapore 389838
🇭🇰 Hong Kong
Debiasia Green Technology (HK) Co. Ltd.
Room 04, 4/F, Wah Fat Industrial Building, 10–14 Kung Yip Street, Kwai Chung, Hong Kong
Reply usually within a business day. Comfortable with both residential and industrial scopes.
Ultra Thin Series
UV-C Sterilization Lamp
Eliminates 99.9% Bacteria and Viruses in the Air.
Humidity Control at Your Fingertips
LCD screen, Tuya mobile app, and RS485 Modbus smart home connectivity.
Auto Pump Drainage
Head Lift up to 1.8 meters.
Metal Cast Motor
Stable and Durable. Features Japan NSK Bearing.
40dB Quiet Operation
Multiple Shock-Absorbing Designs.
DBA-UTC20
20L/day
Studio or single-room size. R410A refrigerant, single inlet.
HK Grade 1 Energy Label
200–400sqft area
39dB(A) @ 3m
⌀146flange in/out
DN15drain outlet
Performance
- Moisture removal
- 20 L/day @ 30°C 80%RH
9.9 L/day @ 26.7°C 60%RH - Max airflow
- 220 m³/hr
- Static pressure
- 80 Pa
- Sound @ 3 m
- 39 dB(A)
- Coverage
- 200 – 400 sqft
- Operating temp
- 5 – 40 °C
Power
- Voltage
- 220 – 240 V ~ 50 Hz
- Rated power
- 196 W
- Max power
- 300 W
- Rated current
- 1.0 A
- Max current
- 1.35 A
Drainage & ducting
- Pump lift
- 1.8 m (built-in check valve)
- Drain outlet
- DN15
- Air flange ⌀
- 146 mm
- Refrigerant
- R134a · 0.23 kg
Physical & certs
- Dimensions (L×W×H)
- 865 × 376 × 200 mm
- Net weight
- 28 kg
- Certifications
- CE · CB · RoHS
DBA-UTC55
55L/day
Mid-size between UTC20 and UTC68. Uses R32 refrigerant, the EU environmental standard.
R32 · A2L
600–800sqft area
45dB(A) @ 3m
⌀146flange in/out
DN15drain outlet
Performance
- Moisture removal
- 55 L/day @ 30°C 80%RH
30 L/day @ 26.7°C 60%RH - Max airflow
- 600 m³/hr
- Static pressure
- 90 Pa
- Sound @ 3 m
- 45 dB(A)
- Coverage
- 600 – 800 sqft
- Operating temp
- 5 – 40 °C
Power
- Voltage
- 220 – 240 V ~ 50 Hz
- Rated power
- 700 W
- Max power
- 930 W
- Rated current
- 3.2 A
- Max current
- 4.3 A
Drainage & ducting
- Pump lift
- 1.8 m (built-in check valve)
- Drain outlet
- DN15
- Air flange ⌀
- 146 mm
- Refrigerant
- R32 · 0.3 kg (mildly flammable)
Physical & certs
- Dimensions (L×W×H)
- 970 × 436 × 238 mm
- Net weight
- 38 kg
- Certifications
- CE · CB · RoHS · A2L
DBA-UTC68 · popular
68L/day
The whole-apartment workhorse. R410A refrigerant, single inlet.
800–1000sqft area
48dB(A) @ 3m
⌀146flange in/out
DN15drain outlet
Performance
- Moisture removal
- 68 L/day @ 30°C 80%RH
42 L/day @ 26.7°C 60%RH - Max airflow
- 500 m³/hr
- Static pressure
- 100 Pa
- Sound @ 3 m
- 48 dB(A)
- Coverage
- 800 – 1000 sqft
- Operating temp
- 5 – 40 °C
Power
- Voltage
- 220 – 240 V ~ 50 Hz
- Rated power
- 880 W
- Max power
- 1250 W
- Rated current
- 4.0 A
- Max current
- 5.7 A
Drainage & ducting
- Pump lift
- 1.8 m (built-in check valve)
- Drain outlet
- DN15
- Air flange ⌀
- 146 mm
- Refrigerant
- R410A · 0.6 kg
Physical & certs
- Dimensions (L×W×H)
- 1010 × 500 × 240 mm
- Net weight
- 42 kg
- Certifications
- CE · CB · RoHS
DBA-UTC120
120L/day
Large homes and light commercial. R410A refrigerant, twin-inlet.
Twin inlet ⌀196
1300–1500sqft area
50dB(A) @ 3m
⌀196flange in/out
DN15drain outlet
Performance
- Moisture removal
- 120 L/day @ 30°C 80%RH
53 L/day @ 26.7°C 60%RH - Max airflow
- 890 m³/hr
- Static pressure
- 100 Pa
- Sound @ 3 m
- 50 dB(A)
- Coverage
- 1300 – 1500 sqft
- Operating temp
- 5 – 40 °C
Power
- Voltage
- 220 – 240 V ~ 50 Hz
- Rated power
- 1010 W
- Max power
- 1600 W
- Rated current
- 4.7 A
- Max current
- 7.4 A
Drainage & ducting
- Pump lift
- 1.8 m (built-in check valve)
- Drain outlet
- DN15
- Air flange ⌀
- 196 mm · twin inlet, single outlet
- Refrigerant
- R410A · 0.9 kg
Physical & certs
- Dimensions (L×W×H)
- 1075 × 746 × 310 mm
- Net weight
- 64 kg
- Certifications
- CE · CB · RoHS
Good to Know
Straight answers to the questions people ask before putting a dehumidifier in the ceiling. Tap a question to open it.
01
One unit, every room — whole-house dehumidification
One hidden machine above the false ceiling, with ducts branching to each room. Here's how that actually works.
Planning What do I need to know before installing one?
A ceiling dehumidifier is installed completely out of sight, so the real question is whether your home has a suitable spot for it. Most flats do — common locations are above the corridor false ceiling, the bathroom ceiling, or a bulkhead over the storeroom or kitchen.
- Ceiling depth — around 20–30 cm above the false ceiling, depending on model. Corridors and bathrooms usually have this already.
- An access panel — a small ceiling hatch below the unit, the same kind used for concealed air conditioning. The washable filter comes out through here.
- A drain connection — condensate is pumped away automatically. The built-in pump lifts water up to 1.8 m, so the unit does not need to sit right beside a drain.
- A power supply — one dedicated circuit from the distribution board, arranged as part of the installation.
During a renovation, all of this is routine work for the contractor. In a finished flat it depends on ceiling access — a floor plan and a few photos are usually enough for us to confirm whether it is feasible. The full technical detail is in the installation guide.
Coverage Can one unit really dry the whole flat?
Yes — this is the standard configuration, not a special case. The unit is installed at a central point, typically above the corridor, and ducts distribute dry air to each room. One unit supports up to 5 supply outlets and 5 return outlets.
A typical three-bedroom flat: the unit sits above the corridor, with one outlet serving the living room and one in each bedroom. Air returns through a grille near the unit, is dried, and is sent back out — a continuous loop through the whole flat. Larger or split-level homes are usually better served by two smaller units covering separate zones.
Appearance What will the air outlets look like?
Slim ceiling grilles — the same kind you'd see with concealed air conditioning. Each room gets one small supply grille (round or linear), plus a return grille near the unit, plus the access hatch. That's everything visible from below.
There is no machine on the floor, no water tank to empty, and no exposed pipework — day to day, the grilles are the only visible sign the system exists.
Comfort Is my room going to get really warm?
The air leaving the outlet is slightly warmer than the air drawn in — this is normal, and it is how the machine works. A dehumidifier condenses water on a cold coil, then passes the dried air over a warm coil before returning it; the heat an air conditioner would reject outdoors stays in the room.
In practice, room temperature rises by 1–2 °C at most, and only while the compressor is running. The heat added is roughly equal to the unit's power draw — a few hundred watts, comparable to one or two additional people in the room. With any air conditioning running, the effect is not noticeable.
Dry air also feels cooler at the same temperature: 26 °C at 55% RH is generally more comfortable than 24 °C at 75%, because perspiration can evaporate properly. Most owners report the flat feeling fresher overall, not warmer.
Sizing Which size do I need?
- 200–400 sq ft (studio, one bedroom) — UTC20
- 400–600 sq ft — UTC55
- 500–1,000 sq ft (typical whole flat) — UTC68, the most common choice
- 1,000–1,500 sq ft (large flat, small office) — UTC120
When in doubt, go one size up. A bigger unit running at part load is quieter, uses barely more energy, and the compressor lasts longer than one running flat-out all day. Rooms kept cold (strong aircon, wine storage) cut real-world capacity by 30% or more — step up a size for those too.
Full specs for all four models are in the product overview.
02
Running cost — vs aircon, vs thermo ventilator
What it draws, what it saves, and how it compares with the machines you already have.
vs Aircon Compared to an aircon, how much can it save?
Start with efficiency: an air conditioner removing moisture uses roughly 1.4–1.8 kWh per litre of water extracted, because drying is only a side-effect of cooling. A dedicated dehumidifier does the same work at 0.4–0.6 kWh per litre — three to four times less energy per litre.
Coverage is the other difference. To control humidity across a whole flat with air conditioning, every unit in every room has to be on — and even running continuously, an aircon typically only brings a room down to around 65% RH, because it stops removing moisture once the set temperature is reached. A single ceiling dehumidifier covers every room through the ducting and holds the entire flat at 50–60%.
Over a month of continuous whole-home humidity control, that difference compounds: one unit of a few hundred watts cycling on demand, against several aircon compressors running around the clock without reaching the target. The gap on the electricity bill is substantial.
The two also work best as a pair: the dehumidifier holds 55% RH, and the aircon only trims temperature — the thermostat can be set 2–3 °C higher with the same comfort. Homes running this combination typically spend 15–25% less than air conditioning attempting both jobs alone.
vs Thermo vent Which uses more power — a thermo ventilator or a ceiling dehumidifier?
The thermo ventilator, by a clear margin. It dries by heating: a PTC element rated at 1,500–2,800 W warms the room air, and the fan extracts that warm, moist air outdoors. It works quickly, but the energy used to heat the air is exhausted along with it — which is why it is normally run for only twenty to thirty minutes at a time.
A ceiling dehumidifier draws 196–880 W rated (UTC20 to UTC68) — roughly one fifth of the power — and removes water through a drain pipe rather than exhausting heated air. It is slower minute for minute, but it is designed for continuous operation, and it holds the entire flat at the target humidity rather than a single bathroom.
In short: the ventilator is faster over the first half hour; over any longer period, the dehumidifier removes far more moisture per unit of electricity.
Bathroom Do I still need a thermo ventilator if I have a ceiling dehumidifier?
They do different jobs. The one thing a thermo ventilator does that a dehumidifier can't is instant warm air — a heated bathroom for winter showers. If you value that, keep it.
For everything else — keeping the bathroom dry between showers, stopping mould on the ceiling and grout, drying towels — the dehumidifier does the same job continuously and at a fraction of the energy. Many owners keep the ventilator purely as a winter heater and let the dehumidifier handle moisture year-round.
24/7 Is it expensive to leave running 24/7?
Running 24/7 is how it's meant to be used — but "running" doesn't mean the compressor grinds non-stop. Once the flat reaches your target humidity, the compressor switches off and only the sensor keeps watch, cutting back in when humidity creeps up.
In a closed flat that's already dried down, a correctly sized unit spends most of the day idle or at part load. The steady-state cost is a small fraction of the rated wattage — far less than the same flat's aircon, and less than repeatedly drying out a damp flat from scratch.
What actually undermines efficiency is not leaving it on — it is running it with windows open. See the next section.
AC's limit Why can't my aircon do the same job?
Because for an air conditioner, dehumidification is a by-product of cooling, not a function it controls. Moisture is only removed while the compressor is running and the coil is cold. Once the room reaches the set temperature, the compressor slows or stops — and moisture removal stops with it, regardless of how humid the room still is.
This is why an air-conditioned room typically settles at 65–75% RH: the aircon regulates temperature, not humidity. Dry mode helps at the margin, but it still works towards a temperature target and cannot hold a humidity setpoint.
The limitation is most obvious in cool, damp weather — a rainy 22 °C day, for example. The aircon cannot dehumidify without also cooling an already-cool room, so the choice becomes cold and clammy, or off and damp. A dehumidifier controls humidity independently of temperature — which is exactly the situation it is built for.
03
Everyday use — windows, fans, laundry
A few everyday habits have a direct effect on how well the system performs.
Windows Can I keep windows open while dehumidifying?
Preferably not. With windows open, humid outdoor air enters faster than any unit can remove moisture — the compressor runs continuously, the humidity never reaches target, and the electricity is spent without result.
Close the windows in the area being treated and the unit reaches its target quickly, then idles. If you want to air the flat, open the windows for ten minutes, close them, and let the machine catch up — in an enclosed space it recovers quickly.
Fresh air My flat is airtight — don't I need fresh air then?
A reasonable concern. Modern flats are built airtight, and a family of four sleeping with windows closed can push bedroom CO₂ to 1,500–2,500 ppm by morning — well above the 1,000 ppm comfort guideline. A standard dehumidifier addresses humidity, not CO₂.
Two ways to square it: air the flat briefly once or twice a day and let the dehumidifier recover afterwards — fine for most households — or install a fresh-air dehumidifier (DBA GEC V series), which dries the flat while drawing in HEPA-filtered outdoor air, modulating automatically on its CO₂ and PM2.5 sensors. Ask us which fits your layout.
Exhaust fan When dehumidifying the bathroom, can I also run the exhaust fan?
During and immediately after a shower — yes. Extracting steam directly outdoors is faster than condensing it, so let the exhaust fan handle the initial burst for ten to fifteen minutes.
What to avoid is running both continuously. An exhaust fan left on draws humid outdoor air into the flat through door gaps and window seams, which the dehumidifier then has to process. The pattern that works: exhaust fan during and after the shower, then off, with the dehumidifier maintaining the space for the rest of the day.
Setpoint What humidity should I set?
55% RH is the default that suits almost everyone — comfortable, mould stays dormant, wooden furniture and floors stay stable. Anywhere in the 50–60% band is fine.
Going lower costs disproportionately more: below 50% the unit's capacity drops and runtime climbs, for little felt benefit. Save the low setpoints for the things that need them — wine storage, camera gear, leather wardrobes at 45–50%.
Laundry Can it dry laundry indoors?
Yes — in practice it is one of the most-used functions. A load of wet laundry releases 1.5–2.5 litres of water into the room; without dehumidification, that moisture is absorbed by walls and wardrobes and becomes the familiar musty smell.
Hang the clothes in a room with a supply grille, close the door, and set 50% — dry by morning, in any weather, without the damp smell that usually comes with drying indoors.
04
Living with it — mould, noise, water
What changes at home once the humidity is finally under control.
Mould What humidity actually stops mould?
Mould needs sustained humidity above roughly 65% to grow. Hold the flat below 60% and growth stops; dust mites decline below 50%. The musty smell in wardrobes usually clears within a week or two of steady control.
Consistency matters more than intensity. Drying a room aggressively once a week achieves little — growth resumes as soon as humidity returns. A ceiling unit holding 55% around the clock is what breaks the cycle, and continuous operation is precisely what it is designed for.
Noise Will I hear it at night?
The range measures 39–50 dB(A) at 3 m depending on model — from quieter than a whisper up to a soft conversation — and there's a false ceiling between you and the machine. On low fan at night, most people describe it as faint airflow, similar to concealed aircon.
What matters more than the spec is the install: rubber isolation on the hanging rods and a flexible duct section at the flange stop vibration travelling into the structure. Done right, a rattling ceiling means something's loose — not that the machine is loud. See troubleshooting if that ever happens.
Drainage Where does all the water go?
Into a drain pipe — automatically, with no tank to empty. A built-in pump lifts the condensate up to 1.8 m, so the pipe can route up and across the ceiling void to the nearest drain point.
Protection is built in: if the drain ever blocks, a water-full sensor stops the machine and shows a fault code on the panel rather than allowing an overflow, and an optional leak-sensor cable in the ceiling shuts the unit down at the first trace of water.
Upkeep How much looking after does it need?
Two habits. Rinse the stainless mesh filter every three months or so — it slides out through the access hatch, washes under the tap, and goes back in once dry. And once a year, have the coil and drain checked; that's what keeps performance at day-one levels for a decade.
The full schedule is in the maintenance chapter.
Installation
01
Start at step 1
Parts & accessories
Body anatomy, package contents.
02Preparation
Bench test, plan.
03Hanging
M10 rods, level, isolate.
04Drainage
1.8 m pump head.
05Ducting
⌀146 / ⌀196 mm collars.
06Controls
LCD panel, humidity sensor.
07Power
13 A 220 V, 2.5 mm².
08Acceptance test
Power-on & drainage test.
Step 02 of 08
Preparation
Before installation, bench-test the unit on the floor. Confirm the dehumidifier runs normally.
10-min bench test
Hatch 450 / 600 mm
Service panel orientation
Compulsory
10-minute bench test, before you hang it
After unboxing, place the dehumidifier on the floor or a workbench and run a 10-minute power-on check. (The unit must be powered on for testing both before and after installation.)
- Unbox — open the carton and lay the dehumidifier flat on the floor. Keep the packaging in case you need to return it.
- LCD control panel — connect the LCD control panel signal cable to terminals 4-7 on the unit.
- Temperature & humidity sensor — connect the temperature & humidity sensor to terminals 1-3 on the unit.
- Power up — a grounded 220-240V socket can be used temporarily.
- Switch on — the fan starts immediately; the compressor follows after a 3-second delay (make sure the unit is in dehumidification mode).
- Force the compressor on — set the humidity target to 40% RH or lower. (If the target is above ambient RH, the compressor will not start.)
- Run for more than 10 minutes in dehumidification mode — listen for any unusual noise from the fan or compressor. Warm air at the outlet means dehumidification is working. You can also hold the temperature & humidity sensor near the outlet — the RH shown on the LCD control panel will gradually drop. There is a metal fan inside the outlet — never put your hands or any object into it.
- Check the LCD control panel — confirm the LCD control panel display and controls work normally, with no fault code shown.
No error code? You can start the install.
Before you start, confirm:
-
Confirm the plenum height — UTC20 needs 200mm, UTC68 needs 240mm, UTC120 needs 310mm — and leave 2-30mm of clearance above and below, so the body never touches the slab or the false ceiling.
- Confirm the hanging position — mark where the four threaded rods will be fixed into the slab, avoiding existing services inside the slab.
-
Pick the hatch location — a hatch of 450 × 450 mm or 600 × 600 mm is recommended, directly in front of the service-panel side (the drainage outlet side).
- Plan duct routes early — sketch the return and supply paths, mark every elbow and count them. Each 90° bend costs about 10 Pa.
Materials needed for installation
Recommended mounting components, all 304 stainless steel:
M10 sleeve anchors × 4to fix the threaded rods into the concrete slab
M10 threaded rods × 4main support rods (cut to length, usually 1–2 m)
M10 hexagonal nuts × 12for height adjustment, levelling, and locking
M10 flat washers × 12distribute load and protect surfaces
M10 lock rings × 12prevent the nuts from loosening due to vibration
Rubber vibration padsat the unit's hanging ears, for ultra-quiet running
Flex + rigid ductaluminium foil flex for most runs; rigid galvanised for longer sections
500 - 1000 mm silenced ductsilenced anti-vibration flex section between the unit flange and the rigid duct
Insulated drain hoseplus an Upper U-trap (check valve is built into the unit)
3 × 2.5 mm² cableand a dedicated 13A 220V power socket
86-type back boxfor the LCD control panel (8 m cable supplied)
Spirit level & tapelevel the unit before final tightening
One thing to never skip.
Don't power the unit on during construction. Drywall dust, cement, sawdust — all of it lands on the coil and kills the compressor. Tape the inlet shut until the room's clean.
Step 03 of 08
Hanging the unit
Suspended from four M10 threaded rods. Keep the body level.
4 × M10 304 SS rods
≥ 2 cm clearance above & below
Rubber vibration washers
How to hang it
- 1Fix four M10 stainless rods into the concrete ceiling. Use the supplied template card to mark the drill holes. Leave at least 2 cm clearance above and below the unit for levelling later.
- 2Slide a rubber washer onto each rod and clamp it above and below the unit foot. The pads keep fan vibration off the slab.
- 3Lift the unit onto the rods, aligning the four mounting holes at the corners.
- 4Use a spirit level on the top or bottom face to confirm the unit is level.
Location & orientation — confirm before drilling
-
Ceiling access hatch — must face the unit's service panel. Never face the service panel into a wall, or future maintenance is blocked.
- Return & supply air vents — at opposite ends of the body. Leave at least 0.5 m of duct-connection space at each end.
- Pump drainage outlet — below the service-panel side.
-
Wired controller, power cable & emergency-stop button — located on the left of the air outlet.
Step 04 of 08
Drainage
UTC series has a built-in auto drain pump with 1.8 m head lift.
1.8 m head drain pump
DN15 drain outlet
Built-in check valve
Upper U-trap
Drainage requirements
- 1Built-in check valve — no need to fit one externally. Prevents condensate from flowing back into the unit.
- 2Fit an Upper U-trap — blocks drain-line air and odours.
- 3Insulate the drain pipe — stops condensation forming on the pipe surface.
- 4Use a flexible hose at the unit's drain outlet — isolates vibration from the unit to the pipe. Never connect rigid pipe directly to the outlet.
- 5Shared drain line — multiple drain pipes can merge into a main drain at the low point. Never tee them at the top.
Pump cycle logic
While the unit runs, the built-in pump cycles 3 minutes on, 5 minutes off. If the drain backs up or the pump fails, the LCD shows fault code E3 (water-full protection).
Before you sign off
Slowly pour 1–2 litres of water into the drain pan through the service hatch. Power on the unit — the pump should kick in within a minute and clear the pan. Then watch every joint on the route for at least five minutes to make sure there is no chance of a leak.
Step 05 of 08
Ducting
Flexible aluminium foil for most runs; rigid galvanised for longer or stiffer sections. Always join the unit flange to the rigid duct via a 300–500 mm flexible section — that's what stops compressor vibration travelling into the rooms.
300–500 mm flex section
Total main duct within 10 m
150 mm or 200 mm duct diameter
- Aluminium foil flex duct is the default — easy to install and quiet. Switch to galvanised rigid for longer runs.
- Total main duct (supply + return) within 10 m. Beyond that, airflow drops as friction losses build up.
- Connect a 300–500 mm flex section at the unit's flange to stop machine vibration from travelling into the duct. Never connect rigid duct straight to the flange.
- For a quieter install, swap the 300–500 mm flex section for a silenced duct section.
-
Keep 1 m of straight duct before the first branch. Avoid sharp bends right after the outlet.
-
Up to 5 supply and 5 return outlets. Branch duct diameter within 75 mm.
Step 06 of 08
Controls
All signal connections must be made with the power off.
LCD panel (8 m signal cable)
Humidity sensor (5 m signal cable)
Dry-contact on/off
Leak-detection cable
Mounting the panel and the humidity sensor
- The control panel is 86 × 86 mm. Mount it on the wall for easy viewing and adjusting the target humidity.
- The humidity sensor can sit at the return-air vent or in a quiet ceiling corner — never in the supply airstream.
Control box — terminal map
The control box sits on the left of the unit, by the air outlet. Terminals 1–7 carry low-voltage signals from the humidity sensor and the control panel. Terminals 8–13 are passive dry-contact inputs — never apply external voltage to any terminal, it will damage the mainboard.
1 – 3
Temperature & humidity sensor
GND · +5V · DATA. The humidity sensor ships with a 5 m signal cable; any shielded multi-core cable works as well — keep total length under 20 m.
4 – 7
Wired control panel
RX · TX · +5V · GND. The LCD panel ships with an 8 m signal cable; any shielded multi-core cable works as well — keep total length under 20 m.
8 – 9
Remote on/off (dry contact)
Short the two terminals via any unpowered switch — third-party switch control. NO (default): short = on, open = off. NC: short = off, open = on (switchable in the control panel's advanced parameters — contact DBA support for details).
10 – 11
Leak-detection cable signal input
Connect a standard leak-detection cable. Moisture anywhere along the cable triggers fault code E7 and an auto-shutdown.
12 – 13
Reserved
For future expansion — do not connect without manufacturer instructions.
RS485 & WiFi
-
RS485 Modbus — A/B ports behind the LCD panel, next to GND/+5V/TX/RX. 9600 bps. Standard Modbus RTU register map for BMS, HMI, PLC.
Download RS485 Protocol PDF
- WiFi via Tuya Smart app — phone on 2.4 GHz WiFi (not 5 GHz). Hold the fan-speed button on the panel until the WiFi indicator flashes, then add the device from the app.
Status & Emergency Stop
- Status indicator LED + emergency stop button on the rear of the unit, next to the power cord outlet — for local diagnostics and a quick local kill switch.
Never feed voltage into terminals 8–13.
These are passive dry-contact inputs. Any external power source — even 5 V — will back-feed into the mainboard and kill the controller. Use only unpowered switches, probes, or sensing cables.
Power off before you touch any signal wire.
Plugging or unplugging the control panel while live will fry the control board. Per the install guide: power down, connect, then power up.
Step 07 of 08
Power
One dedicated circuit, properly earthed. Don't share it with anything else — compressor startup current is high enough to nuisance-trip a shared breaker.
220V 13A
3 × 2.5 mm²
16 A dedicated breaker
Wiring
- Cable — 3 × 2.5 mm² minimum from the consumer unit to the unit's terminal block.
- Breaker — dedicated 16 A type C MCB. RCBO if local code requires it.
- Isolator — reachable from the hatch, for local lock-off during service.
Never open the casing while powered.
The compressor terminals carry several hundred volts during start, and the capacitor stays charged after the breaker trips. Lock off, verify dead, then open.
Step 08 of 08
Acceptance test
Ten minutes of watching the unit run is what separates a clean install from a callback in six weeks.
Warm supply air
No abnormal noise
No fault codes
Drain leak test
10-minute power-on test
- 1Energise. Confirm the LCD panel shows no fault code.
- 2Set to dehumidification mode. Set the target humidity below ambient — only then will the compressor start.
- 3Compressor should start within 90 seconds. A few minutes in, check that warm air is leaving the supply grille.
- 4Listen below the unit and at both grilles. No metallic rattle, no abnormal duct noise.
- 5After 10 minutes, the humidity reading on the LCD panel should start trending down.
- 6Retest the drain. Power off, open the service panel, pour 1 L of water into the tray — the pump should cycle within 5 minutes. Check every joint along the drain line for leaks.
Hand-off
Walk the homeowner through a few things: where the filter is (and how to wash it), how the LCD panel works, and how to pair the DBA app. Leave them the manual, the order receipt, and the unit's serial number — service can help much faster with it on hand.
✓
Double-check every step before you wrap up.
A properly installed ceiling unit, with regular upkeep, will run efficiently and reliably for years.
User Manual
Seven chapters covering the unit end-to-end — safety, anatomy, control panel, operation, app, maintenance, warranty.
01
Start at chapter 1
Control panel
Icons, buttons, what each does.
02Operation
Modes, timer, defrost, fan speed.
03App pairing
Tuya Smart, 2.4 GHz WiFi.
04RS485 Modbus
RS485 wiring, Modbus RTU protocol.
05Routine maintenance
Filter, coil, drain — three intervals.
06Troubleshooting
Symptoms, fault codes, when to call service.
07Safety notes
Grounding, refrigerant, R32 rules.
08Warranty
1-year limited, claims, exclusions.
Chapter 07 of 08
Safety instructions
Observe these at all times. The unit runs on mains voltage and contains pressurised refrigerant — sloppy handling causes shock, fire, or compressor death.
- Not for unsupervised children or persons with reduced physical / sensory / mental capability. Supervise children so they don't play with it.
- Only a properly grounded 220-240 V ~ 50 Hz outlet. Don't modify the plug, don't use an extension cord or an adapter — they overheat.
- Disconnect power before servicing, cleaning, or moving the unit. Unplug by gripping the plug body — never pull on the cord.
- Install per local code. Professional installation by a qualified technician is strongly recommended.
- Keep fingers and objects out of the inlet and outlet. There's a metal fan inside. Keep vents clear.
- Don't expose to flammable gas, corrosives, heavy dust, or direct water. Not for explosive or highly corrosive environments.
- Damaged power cord — must be replaced by the manufacturer, its service agent, or a similarly qualified person.
- Any abnormal sign (unusual noise, smell, smoke) — cut power immediately and call service.
Refrigerant — R410A vs R32
Your refrigerant type is on the rating label on the unit. R410A is not flammable. R32 is mildly flammable (A2L) — if your unit uses R32, observe the following:
- Qualified personnel only for installation and servicing.
- Install, operate, store in a well-ventilated area.
- Never pierce or burn the refrigerant circuit.
- Dispose of the unit per local regulations at end of life.
Step 01 of 08
Parts & accessories
What's in the box, where every port is, and how the unit is laid out. Worth keeping open while you do the install.
Package contents
- Dehumidifier — with a 5 m power cable and a Type G plug.
- Wired control panel — 8 m signal cable, fits an 86-type back box.
- Temperature & humidity sensor — 5 m cable, plugs into terminals 1–3.
- Remote controller — 2 × AAA batteries supplied.
- Installation guide — the wall-mounted marker card with all key dimensions.
Parts to know
- Air inlet & outlet — opposite short sides. Direction of airflow is printed on the top of the unit.
- Dust filter — slides out from the service-panel side. Wash regularly.
- Access panel — long face of the unit. Faces the false-ceiling access hatch.
- Pump drainage outlet — bottom, on the same side as the access panel.
- Wired controls box — small cover next to the air outlet; holds the 13-terminal block.
- Power cord outlet — rear face, next to the emergency stop button and status indicator.
Chapter 01 of 08
LCD control panel
The wired panel does everything — power, mode, fan speed, target humidity, clock, timer, UV. Eleven on-screen icons tell you what state the unit is in.
Display icons
1
WiFi connectionApp connected or in pairing mode.
2
Mainboard disconnectionCommunication fault between the panel and the mainboard.
3
DefrostingAutomatic defrost cycle is active.
4
TimerDaily ON/OFF schedule is enabled.
5
Time displayShows the current time.
6
HumidityCurrent room humidity (%RH).
7
TemperatureCurrent room temperature, in °C.
8
Fan speedTwo speeds — press the fan button to switch.
9
Dehumidify modeDehumidify mode icon stays lit while active.
10
UV-C lampUV-C lamp icon stays lit while on.
11
Power onUnit is powered on.
Buttons
- Power — standby ↔ run. On power-up the fan defaults to High Speed.
- Fan speed — toggles between High and Low. Indicator shows level.
- Mode (M) — cycles Dehumidify / Ventilation. Long-press 3 s to enter clock and timer setup.
- ▲ / Humidity setting — press to enter setup, then ▲ / ▼ to step the target (10 – 95 % RH). Confirms after 5 s of no input.
- ▼ / UV lamp — short-press to toggle the UV lamp on/off (if fitted).
Compressor delayed start
The fan starts immediately, the compressor follows after a 3-second delay every time start conditions are met. That's a design feature, not a fault.
Chapter 02 of 08
Operation
Power, modes, timers, humidity setting, fan speed.
Power on / off
- From standby: press Power → unit starts. Fan defaults to High Speed.
- While running: press Power → standby mode. Buttons and some icons turn off.
- Compressor delay: any time start conditions are met, the fan starts immediately and the compressor follows 3 s later.
Operating modes
Press the Mode button (M) to switch between dehumidify and ventilation.
- Dehumidification (default at power-up) — compressor cycles to hit your target %RH.
- Ventilation — fan only, compressor stays off. Useful for clearing stale air without drying.
Fan speed
Fan defaults to High Speed on power-up. Press the fan button to toggle between High and Low. The speed-bar indicator on the panel reflects the current level.
Clock & timer
- 1Long-press Mode (M) for 3 s to enter clock setup.
- 2▲ / ▼ to set the hour, then press M to move to minutes.
- 3Press M again to set the ON timer (auto power-on time).
- 4Press M again to set the OFF timer (auto power-off time).
- 55 s of inactivity exits setup and saves everything.
Once configured, the unit runs the same ON/OFF schedule every day. To cancel the timer, set both ON and OFF to 00:00.
Drain pump cycle
While the unit runs, the built-in pump cycles 3 min on, 5 min off, repeating. If the drain backs up, the panel shows fault code E3 (water full).
Automatic defrost
- Enters defrost when the compressor has run continuously for 25 minutes and the coil temperature reads ≤ −1 °C for 30 s.
- During defrost the compressor stops, the fan runs at High Speed, and the panel shows the defrost icon.
- Exits defrost after 8 minutes max, or once the coil rises to ≥ 5 °C (after at least 3 minutes of defrost).
- Sensor fault (E1): the unit falls back to timed defrost — 25 min compressor / 8 min defrost.
Compressor restart protection
After the compressor stops, it waits 3 minutes before restarting. That delay protects the compressor — don't power-cycle the unit to "force" it back on.
Chapter 03 of 08
App pairing
Connect the unit to the Tuya Smart app for remote control. The phone needs 2.4 GHz WiFi — 5 GHz won't pair.
Pairing steps
- 1Install the Tuya Smart app from the App Store or Play Store and register an account.
- 2Turn on phone Bluetooth and connect to your 2.4 GHz WiFi network (not 5 GHz).
- 3Put the unit in pairing mode: turn it on, then press and hold the fan-speed button until the WiFi icon flashes on the panel.
- 4In the app, tap "Add Device" — Tuya will discover the dehumidifier automatically.
- 5Enter your WiFi name and password. The app adds the device and opens the mobile control panel.
Third-party service
App features depend on network conditions and the Tuya cloud. The manufacturer isn't responsible for outages caused by your internet, router, or the Tuya platform.
Chapter 04 of 08
Routine maintenance
Three jobs across the year. None of them takes more than ten minutes.
Every 2 weeks
Clean the filter
Per the manual: check the filter at least every two weeks. Open the hatch, slide the mesh filter out. Gently tap or vacuum to remove dust, or wash in warm water (≤ 40 °C) with a little neutral detergent, rinse clean, air-dry completely before refitting.
- In dusty environments: check weekly, or daily if needed.
- Don't expose the filter to direct sunlight or heat sources — it will warp.
- Never refit a damp filter — biofilm starts on day one, and airflow drops.
Yearly
Coil & drain service
Power off at the breaker first. Wipe the casing with a soft, clean, dry cloth — or a cloth lightly dampened with mild detergent for stubborn soiling, then wipe clean with a plain damp cloth. Never rinse or wash the unit with running water — it will cause insulation failure and risk of shock. Run a litre of water through the drain pan to confirm the pump still clears quickly.
If you live above a kitchen or near the sea,
halve every interval. Cooking oil and salt aerosol coat the coil twice as fast.
Chapter 08 of 08
Limited warranty
Effective 1 January 2024. Summary of the warranty card shipped with the unit — keep the original card for any claim.
What's covered
- 1 year from the original purchase date by the first end user, against defects in materials and workmanship under normal use.
- Manufacturer's option — repair or replace the defective product or component.
- Applies only if the unit is installed, operated, and maintained per the manual.
What's NOT covered
- Refrigerant, accessories, consumables (e.g. filters), transport, installation, removal, or labour costs.
- Damage from improper installation, operation, or maintenance, or failure to follow instructions.
- Unauthorised repair or modification, misuse, abuse.
- Environmental damage — corrosion, freezing, water ingress, acts of nature.
- Replacement parts do not extend the original warranty period.
Making a claim
- Submit within the warranty period with valid proof of purchase.
- Service is performed by the manufacturer or an authorised service provider.
- If shipping is required the customer is responsible for packaging, transport costs, and risk of loss.
Contact for service
- Hong Kong — Debiasia Green Technology (HK) Co. Ltd. · +852 2541 1611 · dba@dba.hk
- Singapore — DBA Electric Pte. Ltd. · +65 6772 9962 · dba@dba.sg
To the maximum extent permitted by law, total liability shall not exceed the original purchase price of the product. The manufacturer reserves the right to amend this warranty without notice.
Chapter 05 of 08
RS485 Modbus
RS485 Modbus communication protocol for BMS, HMI, or PLC integration.
-
RS485 Modbus — A/B ports behind the LCD panel, next to GND/+5V/TX/RX. 9600 bps. Standard Modbus RTU register map for BMS, HMI, PLC.
Download RS485 Protocol PDF
Chapter 06 of 08
Troubleshooting
Most "broken" dehumidifiers are starved-airflow units, full filters, or stalled drains. Walk through these before calling service.
Fault codes
E1
Coil sensor faultFalls back to timed defrost. Reseat sensor; if persists, call service.
E2
Temp/humidity sensor faultUnit cannot regulate. Reseat the 5 m sensor cable at terminals 1–3.
E3
Water full protectionDrain pan not clearing. Check pump outlet, U-trap, and pipe slope.
E4
Low refrigerant pressureCall service — do not reset repeatedly.
E7
Water leak sensor triggeredLocate and dry the leak. Code clears automatically.
E8
High exhaust temperatureUsually airflow restriction — check filter and ducting.
E9
Discharge sensor faultCall service.
Output low Not pulling out as much water as it used to
- Pull the filter — if it's grey or matted, rinse under warm water, air dry, refit. Try again for 24 hours.
- Check airflow at the supply grille with the back of your hand. Should feel firm. If it's weak, ducting may have collapsed or kinked.
- Check the coil through the hatch. Frost on the coil at room temp = low refrigerant — call service.
- Confirm the room isn't being constantly re-humidified — open window, wet laundry, plants.
Noise Rattling, knocking, or humming through the ceiling
- Open the hatch and check whether the unit body is touching the slab. If yes, slacken the rod nuts a turn — the rubber washers do the isolating.
- Check the duct connections. Loose flex against a metal collar buzzes — re-clip and tape.
- Knocking on startup is the compressor. Persistent knocking once running = mounting bolts loose or refrigerant charge issue.
Water Dripping from the ceiling or hatch
- Power down first.
- Open the hatch. If water is in the drain pan, the pump's not clearing — check the check valve and the U-trap.
- If water is on top of the supply duct, the duct is sweating — insulate it across the plenum.
- If water is at a joint, reseal with mastic and re-clip.
No power Panel dark, unit unresponsive
- Check the breaker at the DB. If it has tripped, reset once. If it trips again, stop — there's a real fault.
- If the breaker holds, check the isolator at the hatch.
- If both are on but the panel is dark, the panel cable may have loosened — power down, reseat, retry.
Smell Musty smell from the supply grille
- Filter — rinse it. This is the cause 80% of the time.
- Run the UV-C lamp continuously for a few cycles (selectable from the panel).
- If it persists, schedule a yearly coil wipe-down — the coil itself can grow biofilm over time.
壓縮機 Fan runs but compressor never kicks in
- Is the target humidity already below the room reading? The compressor only runs when the room is above the setpoint.
- Confirm the unit is in dehumidify mode, not fan-only mode.
- After the compressor stops there is a 3-minute restart delay by design — wait it out before concluding there's a fault.
App Tuya Smart app can't find the unit
- Phone must be on 2.4 GHz WiFi — the unit does not support 5 GHz or auto-band networks.
- Re-enter pairing mode: hold the fan-speed button on the panel until the WiFi icon flashes.
- If still failing, restart your router and make sure the Tuya app is updated to the latest version.
效果 Unit runs all the time but can't reach the target humidity
- Check for continuous moisture sources: open windows, fresh renovation, wet paint, or drying laundry inside.
- Confirm the filter is clean and that both the return and supply vents are unobstructed.
- The UTC20 and UTC55 have limited coverage. If the space is large, a higher-capacity model may be needed.
除霜 Defrost icon keeps appearing
- Defrost is automatic and normal — it runs for up to 8 minutes whenever the coil drops below −1 °C.
- Frequent defrost in warm weather may indicate low refrigerant or a blocked filter restricting airflow over the coil.
- If the unit defrosts more than once per hour at room temperature, call service.
Normal phenomena
Occasional refrigerant flow sounds during operation and shutdown are normal. Warm air from the outlet in dehumidify mode is also normal.
Do not open the unit yourself
If cleaning the filter and checking the drain does not resolve the issue, contact DBA after-sales service.