Danfoss QT Data sheet

Data sheet
Thermostatic actuator QT
- return temperature control with AB-QM valves
Description
Benefits
QT is a self-acting thermostatic actuator designed to be used as return temperature control thermostat in one-pipe heating systems. QT is dedicated to be used with AB-QM automatic balancing & control valve.
AB-QM together with QT is a complete one-pipe solution: AB-QT.
Main data:
• Setting range: 35-50 °C, 45-60 °C, 65-85 °C
• Designed for AB-QM DN 10-32
• Easy-to-install external surface sensor
Reduces actual riser flow to match heat demand
Improved room temperature control
Reduced overheating of the building
Reduced heating cost
Ordering
QT thermostatic actuator
Setting range
(°C)
45 … 60
35 … 50
65 … 85
fit to
AB-QM
DN 10 -20 003Z0382
DN 25-32 003Z0383
DN 10 -20 003Z0384
DN 25-32 003Z0385
DN 10 -20 003Z0386
DN 25-32 003Z0387
Code No.
Accessories
Typ e
Pocket for submersible sensor
Adapter kit QT (DN 10-20)
Adapter kit QT (DN 25-32)
Sensor pocket kit
QT flow set ting tag
Code No.
003Z0391
003Z0392
003Z0393
003Z0394
003Z0395
AB-QM valves
DN
10 LF 150
10 275 00 3Z1211 00 3Z1201
15 LF 275
15 450 003 Z1212 00 3Z1202
20 900 G 1 A 003Z 1213 G 1 A 003Z1203
25 1.700 G 1¼ A 0 03Z1214 G 1¼ A 00 3Z1204
32 3.200 G 1½ A 0 03Z1215 G 1½ A 003Z1205
Q
(l/h)
max.
Ext. thread
(ISO 228/1)
G ½ A
G ¾ A
Code No. AB-QM
00 3Z1261
003Z1262
Ext. thread
(ISO 228/1)
G ½ A
G ¾ A
Code No.
00 3Z1251
00 3Z1252
© Danfoss | 2018.07 VD.C6.U4.02 | 1
Data sheet Thermostatic actuator QT
Applications
Fig. 1 Fig. 2 Fig. 3
QT is designed to be used in combination with AB-QM in one-pipe heating systems. AB-QM together with QT converts one-pipe heating system into energy efficient variable flow system, where flow in the risers is dynamically adjusted to match the load in the riser by control of return water temperature.
In one-pipe systems flow in the riser is always present. TRV on the radiator controls room temperature by controlling flow through radiator. However, by reducing flow through the radiator, water flow is not reduced but diverted to a by-pass and thus total water flow in the riser remains permanent. Therefore at partial loads water temperature in the pipe is increasing. As a result the riser itself with the by-pass pipe continues to heat the room. This can cause overheating of the room.
After the building is renovated the heating system becomes oversized since the heat losses of the building decrease. As a result overheating issue increases even more.
AB-QM mounted in the riser provides a robust solution that offers reliable balance of one-pipe heating system at all system conditions. As a result, every riser gets design flow – and never more than that. Each riser becomes independent part of installation.
In addition, QT as a self-acting return temperature thermostat installed on AB-QM provides flow control through the temperature of return water in the riser. By this water flow in the riser is dynamically controlled to match the actual load in the riser. This results in improved room temperature control and greatly reduced overheating of the building. Thus one-pipe systems become energy efficient variable flow systems, similar as Two-pipe systems are.
Typical applications are:
- one-pipe vertical riser based heating system (Fig. 1)
- one-pipe horizontal loop based heating system (Fig. 2)
- two-pipe vertical riser based heating system without TRV’s, such as staircase or bathroom risers (Fig. 3)
2 | VD.C6.U4.02 © Danfoss | 2018.07
Data sheet Thermostatic actuator QT
Technical data
General data
Setting range
Temperature tolerance ±3
1)
P-band
Max adm temperature at sensor 90
Capillary tube length m 0.6
Materials
Housing CuZn36Pb2As (CW 602N)
Cone and diaphragm support MPPE (Noryl)
Main spindle (CW 614N) Zn39Pb3
Sensor cap Polypropylene (Borealis HF 700-SA)
Temperature sensor Copper, mat. No. 2.0090
Adapter
Nut
1)
with AB- QM DN 10-20, at 50 % flow setting
2)
with AB-Q M DN 25-32, at 50 % flow setting
QT setti ng 0 (min) QT setti ng 6 (max)
AB-QM 50% setting
°C
DN 10 -20 CuZn39Pb3 (CW 614N), coated with Cu Zn8B
DN 25-32 CuZn39Pb3 (CW 614N)
DN 10 -20 CuZn39Pb3 (CW 614N), coated with Cu Zn8B
DN 25-32 CuZn39Pb3 (CW 614N)
35 … 50 45 … 60 65 … 85
2)
5 1)/8
QT setti ng 0 (min) QT setti ng 6 (max)
AB-QM 50% setting
Mounting
P band P band
P band P ba nd
Fig. 4 Functional graph for QT on AB-QM DN 10-20 Fig. 5 Functional graph for QT on AB- QM DN 25-32
When used in vertical based one-pipe heating system (Fig.1) AB-QM is to be installed after the last radiator in the riser.
In horizontal based heating system (Fig.2) AB-QM can be mounted also elsewhere in the loop, as long as the temperature sensor can be mounted after the last radiator in that loop.
QT should be mounted on the AB-QM by hand.
Installation of the sensor
For proper heat transfer between a heating water pipe and the thermostat sensor, it is very important to apply thermo paste (included in the box) on the surfaces in contact.
Sensor itself can be mounted in any direction. For best performance of QT it is recommended to install sensor facing up (Fig. 7). It can be mounted either above or below sensor head.
Maximum allowed torque is 5 Nm.
It is recommended to insulate the sensor if the thermostat is installed in a very cold place (< 5 °C).
o
r
f
m
r
e
a
n
c
e
Sensor holder
Fastener
p
t
s
e
B
Thermo paste
Fig. 6
Hot water su pply
Fig. 7
VD.C6.U4.02 | 3© Danfoss | 2018.07
Data sheet Thermostatic actuator QT
Settings
QT temperature setting depends on AB-QM flow setting.
It is necessary to set the AB-QM according to required setting before the thermostat is mounted. It is recommended to set AB-QM between 30 and 70 % flow setting.
AB-QM DN 10-20 (45-60 °C)
Temperature
setting
20 % 48.0 50.5 53. 0 55.5 58.0 60.5 63.0
30 % 4 7.0 49.5 52.0 54.5 5 7.0 59.5 62.0
40 % 46.0 48.5 51.0 53.5 56.0 58.5 61.0
50 % 45.0 47. 5 50.0 52.5 55.0 57. 5 60.0
60 % 44.0 46.5 49.0 51.5 54.0 56.5 59.0
70 % 43.0 45.5 48.0 50.5 53.0 55.5 58.0
80 % 42.0 44.5 47.0 49. 5 52.0 54.5 5 7.0
AB-QM (flow set ting)
90 % 41. 0 43.5 46.0 48.5 51. 0 53.5 56.0
100 % 40.0 42.5 45.0 47. 5 50.0 52.5 55.0
QT Sensor setting (turns)
0 1 2 3 4 5 6
AB-QM DN 10-20 (35-50 °C)
Temperature
setting
20 % 38.0 40.5 43.0 45.5 48.0 50.5 53.0
30 % 3 7.0 39.5 42.0 44.5 47.0 49. 5 52.0
40 % 36.0 38.5 41.0 43.5 46.0 48.5 51.0
50 % 35.0 37. 5 40.0 42. 5 45.0 47. 5 50.0
60 % 34.0 36.5 39.0 41.5 44.0 46.5 49.0
70 % 33.0 35.5 38.0 40. 5 43.0 45.5 48.0
80 % 32.0 34.5 37. 0 39.5 42.0 44.5 4 7.0
AB-QM (flow set ting)
90 % 31. 0 33.5 36.0 38.5 41. 0 43.5 46.0
100 % 30.0 32.5 35.0 37. 5 40.0 42. 5 45.0
QT Sensor setting (turns)
0 1 2 3 4 5 6
QT thermostat is set to the desired setting by hand. When minimum or maximum setting is required, QT setting knob is to be moved slightly in opposite direction to ensure optimal performance of the thermostat.
AB-QM DN 25-32 (45-60 °C)
Temperature
setting
20 % 49.5 52.0 54.5 57.0 59. 5 62.0 64.5
30 % 48.0 50.5 53.0 55.5 58.0 60.5 63.0
40 % 46.5 49.0 51.5 54.0 56.5 59.0 61.5
50 % 45.0 47. 5 50.0 52.5 55.0 57. 5 60.0
60 % 43.5 46.0 48.5 51.0 53.5 56.0 58.5
70 % 42. 0 44.5 47.0 49.5 52.0 54.5 5 7.0
80 % 40.5 43.0 45.5 48.0 50.5 53.0 55.5
AB-QM (flow set ting)
90 % 39.0 41.5 44.0 46.5 49.0 51.5 54.0
100 % 37. 5 40.0 42 .5 45.0 47. 5 50.0 52.5
QT Sensor setting (turns)
0 1 2 3 4 5 6
AB-QM DN 25-32 (35-50 °C)
Temperature
setting
20 % 39.5 42.0 44.5 47.0 49.5 52.0 54.5
30 % 38.0 40.5 43.0 45. 5 48.0 50.5 53.0
40 % 36.5 39. 0 41.5 44.0 46.5 49.0 51.5
50 % 35.0 37. 5 40.0 42. 5 45.0 47. 5 50.0
60 % 33.5 36.0 38.5 41. 0 43.5 46.0 48.5
70 % 32.0 34.5 37.0 39. 5 42 .0 44.5 4 7.0
80 % 30.5 33.0 35. 5 38.0 40. 5 43.0 45.5
AB-QM (flow set ting)
90 % 29.0 31.5 34.0 36.5 39.0 41.5 44.0
100 % 27. 5 30.0 32 .5 35.0 37. 5 40.0 42.5
QT Sensor setting (turns)
0 1 2 3 4 5 6
Factory setting is 4.
AB-QM DN 10-20 (65-85 °C)
Temperature
setting
20 % 68.5 71.0 73.5 76. 5 80.0 83.5 87.5
30 % 6 7.0 70.0 72.5 76.0 79.0 82.5 86.5
40 % 66.0 69.0 71.5 75.0 78.5 81.5 85.5
50 % 65.0 68.0 71.0 74.5 77. 5 81.0 85.0
60 % 63.5 67.0 70.5 74.0 76.5 80.0 84.0
70 % 62.0 65.5 69.0 72.5 75. 5 79.0 83.5
80 % 60.5 64.0 67.5 71.0 74.5 78.0 83.0
AB-QM (flow set ting)
90 % 58.5 62. 5 66.0 69.5 73.5 77. 5 82.0
100 % 57.0 61.0 64.5 68.0 72. 5 7 7.0 81.5
QT Sensor setting (turns)
0 1 2 3 4 5 6
AB-QM DN 25-32 (65-85 °C)
Temperature
setting
20 % 72.5 75.0 77. 5 80.0 84.0 88.0 92.5
30 % 70.0 73.0 75.5 78.0 82.0 86.0 90.5
40 % 6 7.5 70.5 73.3 76 .0 80.0 83.5 87. 0
50 % 65.0 68.0 72.0 74.0 77. 5 80.5 85.0
60 % 62.5 65.8 69.2 72.5 76. 5 79.0 84.0
70 % 60.0 64.5 68.5 71. 5 75.5 78.0 83.0
80 % 58.0 63.0 67. 0 70.0 74.0 77.0 81.5
AB-QM (flow set ting)
90 % 56.5 61.0 65.0 69.0 72. 5 76. 5 80.5
100 % 55.0 59.0 63.0 67. 5 71.5 75.5 79.5
QT Sensor setting (turns)
0 1 2 3 4 5 6
4 | VD.C6.U4.02 © Danfoss | 2018.07
Data sheet Thermostatic actuator QT
Commissioning
Flow on AB-QM and temperature setting on QT need to be set to achieve best performance and efficiency of one-pipe heating system.
Recommended is a following 3 steps setting procedure:
1. AB-QM setting
2. QT setting
3. follow up
There are 2 main reasons that influence one-pipe system efficiency and therefore AB-QM and QT setting:
1. renovation status of the building since renovation is a major reason for a heating system to become oversized; generally, after building is renovated (wall & roof insulation, new windows) existing heating system becomes significantly oversized
2. a dynamic nature of the heating load that is changing unpredictably in the building due to partial loads, internal gains and weather conditions.
Note:
After renovation, one of possible steps to improve efficiency of the one-pipe heating system is also optimization (reduction) of supply water temperature. Together with AB-QT if offers additional efficiency improvements where influences mostly upper radiators in the riser/loop. In such case QT setting would practically not need to change.
1. AB-QM setting
Required flow after building renovation is generally much lower than design flow that was calculated at the time building was designed. Flow is to be calculated based on actual heat losses–after renovation. Needed flow calculation is recommended to be based on original Δt. For best performance, recommended flow setting on AB-QM is between 30 and 70 % flow setting.
2. QT setting – Df Dynamic factor method
Temperature setting of the QT is influenced by dynamic factor Df. Last radiator in the riser is normally the one which influences dynamic factor Df at most. Df is to be selected from the table A. Having dynamic factor selected, the correction value of return temperature can be chosen from Fig. B.
There are 2 factor that influence dynamic factor Df:
1. фr, Renovation effectiveness [%]
2. Room type [A or B]
Df can be selected for a building as a whole. However, various risers in the same building can have different characteristics (for example: kitchen compared to sleeping room, riser in the middle of the building compared to the one in the corner, etc). Therefore, for best efficiency also dynamic factor Df on various riser within the same building can be different.
VD.C6.U4.02 | 5© Danfoss | 2018.07
Data sheet Thermostatic actuator QT
Commissioning (continuous)
1st factor, Renovation effectiveness фr describes how much actual heat losses have been reduced after building renovation compared to original, design value. фr can be derived by:
Q
r
r
 

1100
%
Q
n
[Qn] - design heat losses (nominal) [Qr] - actual heat losses (after renovation)
2nd factor depends on the what kind of room is heated by a particular riser. It is based on ISO 13790:
• Room typa A: bedroom room, utility, other rooms with low average internal gains of cca
2
3 W/m
• Room type B: kitchen or living room, with high average internal gains of cca 9 W/m
Table A gives an overview of Df values, based on value of both factors respectively.
Tab le A
Df - Dyna mic factor
Room type A (3 W/m2) 8 19 31 43 54 66 78
Room type B (9 W/m2) 17 29 41 52 64 76 88
0 10 20 30 40 50 60
Having dynamic factor selected for a particular building/riser, the correction value of return temperature can be chosen from Fig. B.
фr =renovation effectiveness [%]
QT setting is calculated so that “return temperature correction” value is combined (summed up) with design return temperature (see examples).
Exampl e 1
2
3. Follow up
Achieved energy efficiency of AB-QT solution depends on QT setting. For maximum results it is strongly recommended to perform follow up on the installation during first year of operation.
A- potent ial
energy savings
area
Water T
QT setting
More savings
Exampl e 2
Return temperature correction [°C]
More conservative
Dynami c factor [%]
Fig. B - Return temperature correction
For further details please contact Danfoss representative or visit http://www.danfoss.com/onepipesolutions
A- potent ial
energy savings
area
Water T
QT setting
Outside T
supply temperature
design return temperature
actual return temperature without QT
actual return temperature with QT
Fig. 8a: QT Energy saving potential- higher QT setting
supply temperature
design return temperature
actual return temperature without QT
actual return temperature with QT
Fig. 8b: QT Energy saving potential- lower QT setting
Outside T
6 | VD.C6.U4.02 © Danfoss | 2018.07
Data sheet Thermostatic actuator QT

Sizing – QT setting design examples
1. Example
Fig. 9 “Typical one-pipe riser with AB-QM & QT installed”
A well renovated building.
Given:
Design temperature system 90/70 °C Room type living room Design specific heat losses (before renovation) qn 33 W/m Specific heat losses (after renovation) qr 17 W/m
2
2
Required
Temperature setting for QT
Solution:
Based on:
• Room type B (for living room)
• And фr = 50 %, where renovation effectiveness фr can be calculated as
q
r
r
1100
 
q
n
17
1100
 
33
%5 0

 
dynamic factor Df 76 % can be identified from table A.
Fig. 9
Based on Df = 76 %, Fig. B gives return temperature correction of –23 °C.
Required QT setting is:
47 °C (70 °C + (–23 °C) = 47 °C)
2. Example
A partly renovated building (for example windows renovated only)
Given:
Design temperature system 90/70 °C Room type bedroom Design specific heat losses qn (before renovation) 49 W/m Actual specific heat losses qr (after renovation) 37 W/m
2
2
Actual riser heat losses Qr 10.950 W
Required:
1. AB-QM size & setting
2. QT temperature setting
3. QT sensor setting (turns)
Solution
1. AB-QM setting is calculated based on actual heat losses after renovation and design ΔT.
Qr
q
p
10950
tC

35
3
sm
204190975
hl482sm1034,1q
AB-QM DN 20 is selected, where needed flow
setting is 53 % for required 482 l/h.
2. QT temperature setting
Riser type 2 in table A is a proper match:
• Room type A (bedroom)
• And фr = 25 %, where renovation
effectiveness фr can be calculated as
r
Q
n
1100
 
Q
r
37
1100
 
 
49
%2 5
 
Dynamic factor Df 37% can be indentified
from table, based on фr value of 25% (between 20 and 30%)
Based on Df = 37%, Fig B gives return
temperature correction of –13°C.
Required QT setting is:
57 °C (70 °C + (–13 °C) = 57 °C)
3. QT sensor setting
Required QT temperature setting AB-QM size DN 20 AB-QM setting 53 %
Solution On page 3, left setting table is selected
that is valid for AB-QM DN10 –20 sizes. In a 50% AB-QM setting row, required 57 °C QT temperature setting corresponds to 5 turns.
5 turns for QT sensor setting is selected.
AB-QM DN 10-20 (45-60 °C)
Temperature
setting
20 % 48.0 50.5 53.0 55.5 58.0 60.5 63.0 30 % 4 7.0 49.5 52.0 54.5 57. 0 59.5 62.0 40 % 46.0 48.5 51.0 53.5 56.0 58.5 61.0 50 % 45.0 4 7.5 50.0 52.5 55.0 57. 5 60.0 60 % 44.0 46.5 49.0 51. 5 54.0 56.5 59. 0 70 % 43.0 45.5 48.0 50.5 53. 0 55.5 58.0 80 % 42.0 44.5 47. 0 49.5 52.0 54.5 57.0
AB-QM (flow set ting)
90 % 41. 0 43.5 46.0 48.5 51.0 53.5 56.0
100 % 40.0 42.5 45.0 4 7.5 50.0 52.5 55. 0
QT Sensor setting (turns)
0 1 2 3 4 5 6
VD.C6.U4.02 | 7© Danfoss | 2018.07
Danfos produc Al
Danfoss A/S
Heating Segment
Data sheet Thermostatic actuator QT
Design
1. Setting knob
2. Adapter
3. AB-QM valve
4. Hot-water pipe
5. Temperature sensor
6. Rubber selling for sensor
7. Sensor holder
Dimensions
DN
H
L
L
1min
10 53 37 105
15 65 31 113
20 82 22 110
25 10 4 19 125
32 130 12 137
L L
mm
1min
H
s can accept no responsibility for possible errors in catalogues, brochures and o ther printed material. Danfoss reserves the right to alter its pro ducts without notice. This also applies to ts already on order provided that such alterations can be m ade without subsequential changes being necessary in specications already agreed.
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heating.danfoss.com +45 7488 2222 E-Mail: heating@danfoss.com
© Danfoss | DHS-SRMT/SI | 2018.078 | VD.C6.U4.02
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