Danfoss STM/AVT/VG, Operating Manual

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6 | © Danfoss | 2017.08 VI.GC.X2.8K
STM
ENGLISH
Safety Notes
Prior to assembly and commissioning to
avoid injury of persons and damages of
the devices, it is absolutely necessary to
carefully read and observe these instructions.
Necessary assembly, start-up, and maintenance
work must be performed only by qualified,
trained and authorized personnel.
Prior to assembly and maintenance work on the
controller, the system must be:
- depressurized,
- cooled down,
- emptied and
- cleaned.
Please comply with the instructions of the
system manufacturer or system operator.
Disposal instruction
This product should be dismantled and
its components sorted, if possible, in
various groups before recycling or disposal.
Always follow the local disposal regulations.
Definition of Application
Safety temperature monitor (actuator) STM is,
in combination with Danfoss valves (STM/VG(F),
VGS) and Danfoss controller combinations (STM/
AVT/VG(F), VGS), used for temperature control
and temperature monitoring of drinking water,
water and water glycol mixtures for heating and
district heating systems.
The controllers STM/VG(F), VGS and STM/AVT/
VG(F), VGS are:
- Type-tested acc. to EN 14597
and protect against exceeding temperatures:
- District heating systems acc. to DIN 4747
- Heating systems acc. to EN 12828 (DIN 4751)
and EN 12953-6 (DIN 4752)
- Water heating systems for drinking and
industrial waters acc. to DIN 4753
The technical parameters on the product labels
determine the use.
Application examples
❶
Safety temperature monitor (actuator) STM can
be combined with:
• VG(F) and VGS valves.
• Combination pieces K2, K3, AVT actuators
and valves mentioned above
Assembly
Admissible Installation Positions
➋
Safety temperature monitor (actuator)with
valves
In combination with VG(F) valves:
- Can be installed in any position
①
.
In combination with VGS valves:
• Medium temperatures up to 160 °C:
- Can be installed in any position ② .
• Medium temperatures > 160 °C:
- Can be installed horizontal and in
horizontal pipelines with the actuator
oriented downwards
③
.
Temperature sensor
• The capillary tube may not be twisted or
buckled. The minimum bending radius is
50 mm.
• The place of installation must be chosen in
a way that the temperature of the medium
is directly taken without any delay. Avoid
overheating of temperature sensor.
• The temperature sensor must be immersed
into the medium in its full length
④
.
• The temperature sensor may be installed in
any position
⑤
.
Installation Location and Installation
Scheme
❸
STM/valve ① ,
STM/AVT/valve flow mounting
②
Valve Installation
❹
1. Clean pipeline system prior to assembly.
2. Install a strainer in front of the controller
①
.
Max. mesh width:
- DN 15-25: 0,5 mm
- DN 32-50: 0,8 mm
3. Install temperature indicators in the system
part to be controlled.
4. Install valve
❹
• The flow direction indicated on the product
label
②
or on the valve
③
must be observed.
• The valve with mounted weld-on tailpieces
may only be spot welded to the pipeline ④ .
The weld-on tailpieces may be welded only
without the valve and seals!
⑤⑥
If these instructions are not observed, high
welding temperatures may destroy the seals.
• Flanges ⑦ in the pipeline must be in parallel
position and sealing surfaces must be clean
and without any damage.
Tighten screws in flanges crosswise in 3
steps up to the maximum torque (50 Nm).
5. Caution:
Mechanical loads of the valve body by
the pipelines are not permitted.
Mounting of safety temperature
monitor (actuator)
❺
Before mounting the actuator, carry out Filling
the system, First start-up and Leak and pressure
tests,
❽❾
.
Place temperature actuator at the valve ① or
combination piece
②
and tighten union nut
with wrench SW 50. Torque 35 Nm.
Insulation
❻
Do not insulate the safety temperature
monitor (actuator) and the valve as well.
Start-up
❼
Note
Valves
①
VG(F) and VGS are normally opened
(NO) valves.
Filling the system and Leak and pressure test
should be done without mounted
temperature actuator ② – valve has to be open.
Filling the system, first start-up
❽
1. Slowly open shut-off devices
①
in the flow
pipeline.
2. Slowly open shut-off devices
②
in the return
pipeline.
Leak and Pressure Tests
❾
Pressure must be gradually increased at the +/-
side of the valve.
Do not test with closed valve!
Non-compliance may cause damages at the
actuator or the valve.
A pressure test of the entire system must be
carried out in accordance with anufacturer’s
instructions.
The maximum test pressure for the valves is:
1,5 × PN
PN - see product label
Putting out of operation
1. Slowly close shut-off devices
①
in the flow
pipeline.
2. Slowly close shut-off devices
②
in the return
pipeline.
Settings
❿
Temperature Setting
The temperature setting range is indicated on
product label
①
.
Pre-conditions
The system must be opened and the flow of the
medium guaranteed.
Procedure:
• Set desired set point by turning the setting
adjuster ② with the delivered Allan key
SW 5
③
.
You may only adjust within the marked
range, see
① .
Turning to the left (couter-clockwise)
increases the set point.
Turning to the right (clockwise) reduces the
set point.
• 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 setting adjuster
⑤
must be
sealed by a sealing wire
④
.
Temperature setting - AVT
(relevant only at STM/AVT/VG(F), VGS
controllers)
See instructions for temperature actuator AVT.
Safety function
⓫
If there is a leakage in the area of the
temperature sensor
①
, the capillary tube
②
,
or the thermostat
③
, the valve is closed by a
pressure spring in the safety thermostat. In this
case safety temperature monitor (actuator)
must be replaced.
Dimensions, Weights
⓬
1) Conical ext. thread acc. to EN 10226-1
2)
Flanges PN 25, acc. to EN 1092-2