Instructions
Type AIT-U
AIT-U / VIG 2 AIT-U / VIS 2
Actuator for temperature control AIT-U
7369189-0 VI.GB.A2.81
Safety Notes
Prior to assembly and commissioning, these Assembly, Start-up, and Maintenance Instructions must be read carefully and observed.
Necessary assembly, start-up, and maintenance work must only be performed by qualified, trained, and authorized personnel.
Prior to assembly and maintenance work at the temperature sensor without immersion pocket or at the immersion pocket, the system must be depressurized, cooled down and emptied.
Please comply with the instructions of the system manufacturer or system operator.
Definition of Application
The actuator AIT-U is used for temperature control in combination with Danfoss valves and Danfoss controller combinations.
The controllers with the actuator AIT-U are type-tested acc. to DIN 3440 and comply with the safety requirements for temperature control and temperature limiting units in heat systems.
Mounting
Application system examples
Permissible Installation Positions
AIT-U / VIG 2
—————————————————————
AIT-U / VIS 2
Installation
1. Install strainer (1) before controller.
2. Observe flow direction (2) on rating plate or valve.
Design with welded end
(3) pin only
(4) weld
3. Rinse system.
Actuator AIT-U Mounting
Before mounting the actuator, carry out the filling of the system and pressure tests, see page 9
Place actuator AIT-U at the valve or combination pise and tighten union nut with wrench SW36.
Torque 35 Nm
Temperature Sensor Installation
- The temperature sensor must be installed as shown on the picture.
- The capillary tube may not be twisted or buckled. The minimum bending radius is 50 mm.
- The place of installation must be chosen in such a way that the temperature of the medium is directly taken without any delay. Avoid overheating of temperature sensor
- The temperature sensor must be immerged into the medium in its full length.
Application examples
Dimensions
| Valve | L by DN | ||||||
| Type | Connection | 15 | 20 | 25 | 32 | 40 | 50 |
| VIG 2 | Flange | 174 | 180 | 180 | 210 | 214 | 214 |
| VIG 2 | Thread | 174 | 180 | 180 | – | – | – |
| VIS 2 | Thread | 247 | 247 | 247 | – | – | – |
Filling the System, Pressure Test
Valves VIG 2, VIS 2
Without actuator the valve is opened, therefore carry out filling the system and pressure tests only without mounted actuator.
VIG 2, VIS 2
Temperature Setting
The setpoint range is marked on the scale carrier.
Pre-conditions
- The system must be open and the flow of the medium guaranteed.
| AIT-U | ||||
| 10-45 | 35-70 | 60-100 | 85-125 | |
| Min | 10 | 35 | 60 | 85 |
| 1 | 14 | 38 | 64 | 91 |
| 2 | 23 | 49 | 78 | 103 |
| 3 | 32 | 58 | 87 | 113 |
| 4 | 39 | 65 | 95 | 122 |
| 5 | 46 | 71 | 102 | 129 |
| Max | 48 | 73 | 129 | 131 |
Procedure
- Adjust to the desired setpoint by turning the setpoint adjuster (1).
Turning to the left increases the setpoint (4).
Turning to the right reduces the setpoint (5).
The position of the setpoint adjuster on a scale value (2) means:
1 lowest setpoint
5 maximum setpoint - Observe temperature indicator.
- Wait for about 3 to 5 Min. until the temperature indicator shows the final value.
- If the device is used as a temperature monitor, the setpoint adjuster (1) must be secured by a sealing wire (3).
Technical Data
Thermostat AIT-U
| Setpoint range Xs | °C | 10 – 45, 35 – 70, 60 – 100, 85 – 125 |
| Time constant T 1) | max. 30 | |
| Transmission coefficient Ks | mm/°C | 0.7 |
| Max. perm. temperature at sensor | °K | 50°K above adjusted setpoint |
| Perm ambient temperature at actuator and sensor | °C | -10 – 70 |
| Nominal pressure on temperature sensor | PN | 25 |
| Connection pipe length | m | 4 |
| Temperature sensor material | Copper / Brass | |
| Setpoint adjuster material | Polyamide glass fiber reinforced | |
| Scale material | Polyamide | |
| Mass | ca. kg | 0,9 |
1) acc. to DIN 3440
Help
| Fault | Possible cause | Remedy |
| Temperature too high | Valve does not close: valve seat, plug or trim is dirty or damaged |
|
| Actuator, temperature sensor or connection stem does not extend |
| |
| Temperature too low | Valve does not open: trim dirty or damaged |
|
Documents / Resources
 | Danfoss AIT-U Actuator For Temperature Control [pdf] Instructions AQ00008644660001-010201, 7369189-0, VI.GB.A2.81, AIT-U Actuator For Temperature Control, AIT-U, Actuator For Temperature Control, For Temperature Control, Temperature Control |
