About Dunham-Bush fan coils
Origin: USA / Malaysia. In Türkiye: Imported; units installed mainly in older projects.
We service all Dunham-Bush fan coil models produced over the years, based on the information on the unit's rating label.
Unit types
Our services for Dunham-Bush fan coils
Dunham-Bush fan coil maintenance
Checks of filters, coil, drain pan, drainage, fan, valves and thermostat; documented periodic maintenance.
Dunham-Bush fan coil faults and repair
On-site repair of water leaks, no cooling, fans not turning, valve and controller faults.
Cleaning and filters
Chemical coil washing, drain pan disinfection, filters cut to size.
Dunham-Bush fan coil spare parts
Supply and fitting of compatible motors, valves, thermostats, pumps and other parts.
Dunham-Bush fan coil error codes
Most Dunham-Bush fan coils run on a 3-speed motor and a simple room thermostat; the manufacturer has not published an error code list for these units. Faults are diagnosed from symptoms and measurements. In projects using an electronic controller or networked thermostat, the codes depend on the controller's own brand.
| Symptom | Possible cause | Details |
|---|---|---|
| Water leaking | Blocked drain, overflowing or cracked drain pan, sweating valve | Fix |
| Cassette condensate pump alarm | Float switch or pump fault, blocked drain | Pump |
| No cooling / no heating | Stuck motorized valve, air in the coil, dirty filter | Fix |
| Fan not turning | Capacitor, motor or speed control | Fix |
| Noise and vibration | Dirty or unbalanced fan wheel, bearing | Fix |
| Weak airflow (ducted type) | Dirty filter, duct connection, low fan speed | Cleaning |
Common thermostat warnings
Warnings shown on Siemens RDF series thermostats, which are often used with Dunham-Bush fan coils:
| Indication | Meaning | What to do |
|---|---|---|
| AL1 | External fault input X1 active (e.g. drain alarm) | Check the device connected to input X1. |
| AL2 | External fault input X2 active | Check the device connected to input X2. |
| FIL | Filter cleaning reminder | Clean the filter and reset the warning. |
| Dew (condensation) symbol | Condensation detected in the room, cooling stopped | Check humidity and water temperature. |
Is your Dunham-Bush fan coil showing a code?
Send a photo of the controller display and the unit's rating label and we will interpret it right away.
Dunham-Bush fan coil controllers and thermostats
On Dunham-Bush fan coils we replace faulty or outdated thermostats with new models suited to the unit's 2/4-pipe configuration, valve type and motor speeds: mechanical, digital, weekly programmable and Modbus / BACnet / KNX networked options. Thermostat options →
Dunham-Bush fan coil spare parts
Dunham-Bush fan coil motor
Compatible part supply and fitting
Dunham-Bush capacitor
Compatible part supply and fitting
Dunham-Bush fan wheel
Compatible part supply and fitting
Dunham-Bush motorized valve
Compatible part supply and fitting
Dunham-Bush actuator
Compatible part supply and fitting
Dunham-Bush thermostat
Compatible part supply and fitting
Full spare parts catalog (28 parts) →
Dunham-Bush fan coil service in Ankara
We service Dunham-Bush fan coils on-site in every district of Ankara. We prepare bulk maintenance plans for office towers, hospitals, hotels, schools, shopping malls and residential complexes. For Dunham-Bush units outside Ankara, we start with a pre-diagnosis from photos and videos, followed by a scheduled visit with the required parts.
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Ventas fan coil serviceTeknogenTeknogen fan coil serviceFrequently asked questions
Do you service Dunham-Bush fan coils on-site in Ankara?
Yes. Our base is in Etimesgut; we carry out on-site maintenance, fault repair and part replacement on Dunham-Bush fan coils in every district of Ankara. For Dunham-Bush units outside Ankara we provide scheduled service across Türkiye.
Are you the authorized Dunham-Bush service?
No. YOİ Mühendislik is an independent service holding the TSE Service Adequacy Certificate (HYB No: 12850); we service all brands, including Dunham-Bush, independently of the manufacturer. For units still under warranty, we recommend checking the manufacturer's terms first.
What does a Dunham-Bush fan coil error code mean?
Many Dunham-Bush fan coils are 3-speed units with a simple thermostat and have no published error code list. If you see a code on the display of a model with an electronic controller, send us a photo and we will interpret it based on the controller and board model.
Are Dunham-Bush fan coil spare parts available?
For parts such as motors, capacitors, motorized valves, actuators, thermostats, drain pans, condensate pumps, filters and fan wheels, we supply original parts that fit Dunham-Bush units or equivalents whose technical ratings match exactly. A photo of the rating label is enough.
How often should Dunham-Bush fan coils be serviced?
A full service at least twice a year, before the cooling and heating seasons; filter checks are recommended every 1–3 months depending on usage.