Kromschroeder TC Manual

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Tightness control TC
Technical Information · GB
3 Edition 07.14
AGA
• Test of two safety valves
• Short test period thanks to logical decision-making in the program sequence
• Adjustable test period which can be adapted to different systems
• Adjustable test instant allows quick system start
• Maximum safety thanks to self-monitoring electronics
• Less space required thanks to small dimensions
• EU certified
• UL listed, FM and AGA approved

TC ·Edition 07.14
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Contents
Tightness control TC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
1 Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .....3
1.1 Examples of application....................................................6
1.1.1 TC 116V with valVario controls.....................................................6
1.1.2 TC 116W with combination control CG..D or CG..V ................7
1.1.3 TC 116W with two-stage combination control CG..Z...............8
1.1.4 TC 2 with two gas solenoid valves...............................................9
1.1.5 TC 2 with two gas solenoid valves and one auxiliary valve for
discharge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
1.1.6 TC 2 with two gas solenoid valves and one auxiliary valve for
discharge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
1.1.7 TC 2 in a multiple burner system with 3 valves installed
in series . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
1.1.8 TC 3 with two gas solenoid valves.............................................13
1.1.9 TC 3 with a manually resettable valve......................................14
1.1.10 TC 3 in a multiple burner system with 3 valves installed
in series . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
1.1.11 TC 4 with two gas solenoid valves ............................................16
1.1.12 TC 4 with two gas solenoid valves and one auxiliary valve for
discharge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .17
1.1.13 TC 4 in a multiple burner system with two auxiliary valves for
supply and discharge ......................................................................18
1.1.14 TC 4 in a multiple burner system with 3 valves installed
in series . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
2 Certification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
3 Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
3.1 Connection diagrams ......................................................21
3.1.1 TC 116V for valVario controls VAS, VAG and VAD . . . . . . . . . .21
3.1.2 TC 116W...........................................................................................21
3.1.3 TC 2 ..................................................................................................22
3.1.4 TC 3 ..................................................................................................22
3.1.5 TC 4 ..................................................................................................23
3.2 Program sequence............................................................24
3.3 Test instant...........................................................................26
3.3.1 Testing before burner run: Mode 1 ..............................................26
3.3.2 Testing after burner run: Mode 2...................................................27
3.4 Power failure.................................................................28
3.5 Animation ....................................................................29
3.6 Test period tP...............................................................30
3.6.1 Leakage rate VL...................................................................30
3.6.2 Test volume VP......................................................................31
3.6.3 Calculation example...........................................................32
3.6.4 Calculating the test period tP............................................32
4 Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
4.1 Selection table .........................................................33
4.2 Type code ................................................................33
5 Project planning information . . . . . . . . . . . . . . . . . . . . .34
5.1 Selecting the auxiliary valves .................................34
5.2 Start rate ...................................................................35
5.3 Installation.................................................................35
5.4 Determining the relief line size................................35
5.4.1 TC 116V for valVario controls ............................................36
5.4.2 TC 4.......................................................................................36
6 Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
6.1 Adapter plate for TC 116V, attachment to valVario
controls .........................................................................37
6.2 External pressure switch for TC 4..............................38
6.2.1 Adjustment ...........................................................................38
7 Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
7.1 Indicators and operating controls............................40
7.2 Dimensions ..................................................................41
7.2.1 TC 1, TC 2.................................................................................41
7.2.2 TC 3, TC 4 ................................................................................42
7.3 Converting units.............................................................43
8 Maintenance cycles . . . . . . . . . . . . . . . . . . . . . . . . . . . .44
9 Legend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

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TC 1, TC 2
TC 3
TC 4
TC 1: for attachment
to valVario controls
and CG TC
2: for quick opening
individual
valves
1 Application
TC 1
TC 3: for quick or slow
opening or manually
reset- table individual
valves
TC 4: for control
cabinet installation
The tightness control TC checks the fail-safe function of both
valves before each start-up or after each shut-down of a sys-
tem with two safety valves.
The aim is to identify an inadmissible leak on one of the gas
valves and to prevent burner start. The other gas valve con-
tinues working properly and takes over the safe shut-off of the
gas supply.
It is used in industrial thermoprocessing equipment, in boilers and
forced draught burners.
European standards EN 746-2 and EN 676 stipulate tightness
controls for capacities over 1200 kW (NFPA 86: from 117 kW or
400,000 Btu/h in conjunction with a visual indicator). Pre- purge of
the combustion chamber can be dispensed with under certain
conditions in accordance with EN 746-2, if a tightness control is
used. In this case, the system must be vented into the open air.
Tightness control TC 1 can be directly mounted to all CG
com- bination controls. There is only one version for all
sizes. The pre-set test period applies to all CG variants.
In addition, TC 1 can be used for valVario controls VAS,
VAD and VAG (with separate adapter plate, see page
37 (Ac- cessories)).
TC 2 and TC 4
Tightness controls TC 2 and TC 4 can be used with gas
solenoid valves of any nominal size, which are quick
opening or slow opening with start rate. It is possible to
conduct a tightness test on pneumatically operated or
slow opening valves without start rate by using additional
auxiliary valves.

TC ·Edition 07.14
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Slow opening motorized valves VK up to DN 65 which are
directly flanged together can also be checked by TC 2
and TC 4 within a temperature range of 0 to 60°C
(32 to 140°F).
TC 4
Tightness control TC 4 consists of detection circuitry and
can be installed in the control cabinet, separately from the
system. An external pressure switch takes over the
mechanical pressure test between the valves. Tightness
control TC 4 is independent of gas type and inlet pressure
puand can be used for a test period of up to 10 minutes
with a large test volume.
TC 3
Tightness control TC 3 is a universal device for quick and
slow opening gas solenoid valves of any nominal size as
well as for motorized valves. The tightness test is
carried out with the valves installed in TC 3.

TC ·Edition 07.14
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TC 1 mounted to a
combination control
CG
TC 2 in a gas inlet
section between
a quick open-
ing and a slow
opening gas so-
lenoid valve VG
TC 1 on a double
solenoid valve in an
inlet section
TC 3 for tightness control on
gas motorized valves VK
TC 4 installed in control
cabinet by securing the lower
section with screws or
snapping it on to a DIN rail
TC 4 installed sepa-
rately from
the system in a
control cabinet
it on to a DIN rail

TC ·Edition 07.14
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1 .1 Examples of application
1 .1 .1 TC 116V with valVario controls
Tightness control TC 1 checks gas solenoid valves V1 and
V2 for tightness.
If both valves are tight, the tightness control forwards the
OK enable signal to the automatic burner control unit
GFA. This opens valves V1 and V2 simultaneously. The
burner starts.
V1: quick or slow opening valve with start rate.
A = Supply and signal
forwarding B = Automatic
burner control unit C = Gas
solenoid valves
PZ = Internal pressure sensor of the TC for the comparison
of inlet pressure p
u
and interspace pressure p
z
V
P
= Test volume
TC
1
TC 1
PZ
p
u
2
VA
S
VA
D
pu
V
1
p
Z
VP
V
2
L1(+
)
N(-)
PE
O
K
GF
A
1 2 3
B
1 3 5 6
A
TC 116V
1 2 3
C
V1
V
2

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1 . 1 . 2 TC 116W with combination control CG . . D or CG . . V
Tightness control TC 1 isdirectlymounted to combination
control CG..D or CG..V and checks gas solenoid valves
V1 and V2 in the combination control for tightness.
Once the tightness test has been carried out successfully,
the tightness control forwards the OK enable signal to the
automatic burner control unit GFA. This opens valves V1
and V2 in the combination control CG simultaneously. The
burner starts.
V1 and V2: quick opening valves.
A = Supply and signal
forwarding B = Automatic
burner control unit C = Gas
solenoid valves
PZ = Internal pressure sensor of the TC for the comparison
of inlet pressure p
u
and interspace pressure p
z
V
P
= Test
volume
TC 1
TC1
PZ
CG
p
u
2
PZ
V1
V2
pu
p
Z
VP
L1(+)
N(-)
PE
OK
GFA
1 2 3 B
1 3 5 6 A
TC 116W
1 2 3
C
CG
V1 V2

TC ·Edition 07.14
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1 . 1 . 3 TC 116W with two-stage combination control
CG . . Z
Tightness control TC 1 checks gas solenoid valves V1 and
V2 in combination control CG..Z for tightness.
Once the tightness test has been carried out successfully,
the tightness control forwards the OK enable signal to the
automatic burner control unit GFA. The pilot valve output
of the automatic burner control unit GFA opens valves V1
and V2 in the combination control simultaneously. The
burner starts. The main valve output opens the two-stage
valve VZ, independently of TC 116W.
V1 and V2: quick opening valves.
A = Supply and signal
forwarding B = Automatic
burner control unit C = Gas
solenoid valves
PZ = Internal pressure sensor of the TC for the comparison
of inlet pressure p
u
and interspace pressure p
z
V
P
= Test
volume
TC 1
TC1
PZ
CG..Z
p
u
2
V1
V2
VZ
pu
PZ
p
Z
VP
L1(+
) N(-
) PE
OK
GFA
1 2 3 B
1 3 5 6 A
TC
116W
1 2 3
C
CG..Z
V1 V2
VZ
1 2
3

TC ·Edition 07.14
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1 . 1 . 4 TC 2 with two gas solenoid valves
Tightness control TC 2 checks gas solenoid valves V1
and V2 for tightness.
If both valves are tight, the tightness control
forwards the OK enable signal to the automatic
burner control unit GFA. This opens valves V1 and V2
simultaneously. The burner starts.
V1 and V2: quick or slow opening valves with start
rate.
A = Supply and signal
forwarding B = Automatic
burner control unit C = Gas
solenoid valves
PZ = Internal pressure sensor of the TC for the
comparison of inlet pressure p
u
and
interspace pressure p
z
V
P
= Test volume
TC
2
TC 2
PZ
p
u
2
V1
V2
p
u
p
Z
V
P
L1(+
) N(-
) PE
OK
GFA
1 2 3 B
1 3 5 6 A
TC 2
1 2 3 C
V1
V
2

TC ·Edition 07.14
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1 . 1 . 5 TC 2 with two gas solenoid valves and one
auxiliar y valve for discharge
Tightness control TC 2 checks the gas solenoid valves V1
and V2 and the auxiliary valve V3 for tightness.
It must be ensured that the interspace is vented during the
2-second opening time. This is not guaranteed by the gas
pressure regulator downstream of V2. The test volume VPis
thus discharged into the combustion chamber or into a
safe area. Auxiliary valve V3 can also be used as a pilot
gas valve. Since valve V2 remains closed during the test, it
can also be a slow opening motorized valve VK.
Once the tightness test has been carried out successfully,
the tightness control forwards the OK enable signal to the
automatic burner control unit GFA. The pilot valve output
of the automatic burner control unit GFA opens the gas
solenoid valves V1 and V3 simultaneously. The main valve
output opens gas solenoid valve V2. The burner starts.
V1 and V2: quick or slow opening valves with start rate.
V3: quick or slow opening valve with start rate, nominal
size is dependent on test volume VPand inlet pressure
pu, see page 34 (Project planning information), but is at
least DN 15.
A = Supply and signal
forwarding B = Automatic
burner control unit C = Gas
solenoid valves
PZ = Internal pressure sensor of the TC for the comparison
of inlet pressure p
u
and interspace pressure p
z
TC 2
TC 2
V3
PZ
p
u
2
V1
V2
p
u
p
Z
V
P
L1(+)
N(-)
PE
OK
GFA
1 2 3 B
1 3 5 6 A
TC 2
1 2 3
C
V1 V3
V2

TC ·Edition 07.14
12

ADD FURNACE CO.,LTD.
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1 . 1 . 6 TC 2 with two gas solenoid valves and one
auxiliar y valve for discharge
Tightness control TC 2 checks the gas solenoid valves V1
and V2 and the auxiliary valve V3 for tightness.
If all the gas solenoid valves are tight, the tightness control
forwards the OK enable signal to the automatic burner
control unit GFA. The pilot valve output of the automatic
burner control unit GFA opens the gas solenoid valves V1
and V2 simultaneously. The burner starts.
A relief line is used to discharge the test volume VPinto a
safe area. Thanks to the installed auxiliary valve V3, valve
V2 can also be a slow opening motorized valve VK.
V1: quick or slow opening valve with start rate.
V2: any.
V3: quick opening, nominal size is dependent on test
volume VPand inlet pressure pu, see page 34 (Project
plan-ning information), but is at least DN 15.
A = Supply and signal
forwarding B = Automatic
burner control unit C = Gas
solenoid valves
PZ = Internal pressure sensor of the TC for the comparison
of inlet pressure p
u
and interspace pressure p
z
TC 2
TC 2
PZ
p
u
2
V1
V2
pu
p
Z
VP
L1(+)
N(-)
PE
OK
GFA
1 2 3 B
1 3 5 6
A
TC 2
1 2 3 C
V1 V3
V2
V3

TC ·Edition 07.14
13

ADD FURNACE CO.,LTD.
44 ซอยบรมราชชนนี 
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1 .1 .7 TC 2 in a multiple burner system with 3 valves
installed in series
When using slow opening main valves (V1 and V2), auxiliary
valves (V3 and V4) must be used for the supply and discharge of
the test volume VP.
Tightness control TC 2 checks the central shut-off valve V1, the
gas solenoid valve V2 and the auxiliary valves V3 and V4 for
tightness.
Valve V2 can only be checked for tightness when the pressure
downstream of V2 approximately corresponds to the atmos-
pheric pressure and the volume downstream of valve V2 is 5 x
VP. The gas solenoid valve VAS and the pressure switch DGVAS
are used to relieve the pressure. The pressure switch must be
adjusted in such a way so that enough pressure is relieved and
no air can get into the pipework.
Once the tightness test has been carried out successfully, the
tightness control TC 2 opens the main valves V1 and V2 with the
OK enable signal and enables the downstream burner control
units.
V3 and V4: quick opening, nominal size is dependent on test
volume VPand inlet pressure pu, see page 34 (Project plan-
ning information), but is at least DN 15.
A = Supply and signal forwarding B
= Automatic burner control unit C =
Gas solenoid valves
PZ = Internal pressure sensor of the TC for the comparison
of inlet pressure p
u
and interspace pressure p
z
PZ = Pressure switch DGVAS for monitoring the pressure
down- stream of V2
TC 2
TC 2
PZ
p
u
2
V1
V2
p
u
p
Z
V
P
V3
L1(+)
N(-)
PE
OK
1 3 5 6
A
TC 2
1 2 3 B
V2
K1
DG
VAS
1 2 3
C
V1
K1
VAS
V3
V4
V4
VA
S
PZ
DG
VA
S

TC ·Edition 07.14
14

ADD FURNACE CO.,LTD.
44 ซอยบรมราชชนนี 
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1 . 1 . 8 TC 3 with two gas solenoid valves
Tightness control TC 3 checks the slow opening gas
solenoid valves or motorized valves VK for tightness
using the auxiliary valves installed in TC 3.
Once the tightness test has been carried out
successfully, the tightness control forwards the OK
enable signal to the automatic burner control unit
GFA. The pilot valve output of the automatic burner
control unit GFA opens valves V1 and V2
simultaneously. The burner starts.
V1 and V2: any.
A = Supply and signal forwarding
PZ = Internal pressure sensor of the TC for the
comparison of inlet pressure p
u
and
interspace pressure p
z
p
d
= Outlet
pressure V
P
= Test
volume
TC 3
TC 3
PZ
pu
p
u
2
pd
V1
V2
p
u
p
Z
V
P
L1(+)
N(-)
PE
OK
GFA
A
TC 3
V1
V2
1
3
5
6

TC ·Edition 07.14
15

ADD FURNACE CO.,LTD.
44 ซอยบรมราชชนนี 
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1 . 1 . 9 TC 3 with a manually resettable valve
Valves, which are manually reset, cannot be opened by
the tightness control. The tightness test is then carried out
using an additional auxiliary valve.
Tightness control TC 3 checks the tightness between the
manually resettable valve V1 and gas solenoid valve V2
using the auxiliary valves installed in TC 3.
Once the tightness test has been carried out successfully,
TC 3 forwards the OK enable signal.
V1 and V2: any.
A = Supply and signal forwarding
PZ = Internal pressure sensor of the TC for the comparison
of inlet pressure p
u
and interspace pressure p
z
p
d
= Outlet
pressure V
P
= Test
volume
TC 3
TC 3
PZ
pu
p
u
2
pd
V1
V2
p
u
p
Z
V
P
L1(+)
N(-)
PE
OK
GFA
A
TC 3
V1
V2
1
3
5
6

TC ·Edition 07.14
16

ADD FURNACE CO.,LTD.
44 ซอยบรมราชชนนี 
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1 .1 .10 TC 3 in a multiple burner system with 3 valves
installed in series
Tightness control TC 3 checks the slow opening main
valves V1 and V2 for tightness. The test volume VPis
supplied and discharged via the TC 3 auxiliary valves.
Valve V2 can only be checked for tightness when the
pressure downstream of V2 approximately corresponds to
the atmospheric pressure and the volume downstream of
valve V2 is 5 x VP. The gas solenoid valve VAS and the
pressure switch DGVAS are used to relieve the pressure.
The pressure switch must be adjusted in such a way so
that enough pressure is relieved and no air can get into
the pipework.
Once the tightness test has been carried out successfully,
the tightness control TC 3 opens the main valves V1 and
V2 with the OK enable signal and enables the
downstream burner control units.
V1 and V2: any.
A = Supply and signal forwarding
PZ = Internal pressure sensor of the TC for the
comparison of inlet pressure p
u
and interspace
pressure p
z
PZ = Pressure switch DGVAS for monitoring the pressure
downstream of V2
p
d
= Outlet pressure
TC 3
TC 3
PZ
pu
p
u
2
pd
V1
V2
pu
p
Z
VP
L1(+)
N(-)
PE
OK
A
K1
DG
VAS
V2
TC 3
VAS
V1
K1
1
3
5
6
VA
S
PZ
DG
VA
S

TC ·Edition 07.14
17

ADD FURNACE CO.,LTD.
44 ซอยบรมราชชนนี 
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1 .1 .11 TC 4 with two gas solenoid valves
Tightness control TC 4 checks gas solenoid valves V1 and
V2 for tightness.
The external pressure switch DG monitors the pressure be-
tween the two valves.
Once the tightness test has been carried out successfully,
the tightness control forwards the OK enable signal to the
automatic burner control unit GFA. The pilot valve output
of the automatic burner control unit GFA opens the gas
solenoid valves V1 and V2 simultaneously. The burner
starts.
V1 and V2: quick or slow opening valves with start rate.
p
u
= Inlet pressure
V
P
= Test volume
TC 4
DG
PZ
p
u
2
V1
V2
p
u
p
Z
V
P
TC 4
OK
GFA
1 2 3
4
5 6 7 8 9 10 11 12 13
PZ
V2
V1
L1(+)
N(-)

TC ·Edition 07.14
18

ADD FURNACE CO.,LTD.
44 ซอยบรมราชชนนี 
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1 .1 .12 TC 4 with two gas solenoid valves and one
auxiliary valve for discharge
Tightness control TC 4 checks the gas solenoid valves V1
and V2 and the auxiliary valve V3 for tightness.
It must be ensured that the interspace is vented during the
2-second opening time. This is not guaranteed by the gas
pressure regulator upstream of V2. A relief line is thus used
to discharge the test volume VPsafely into the combustion
chamber or into a safe area. Since valve V2 remains
closed during the test, it can also be a slow opening
motorized valve VK.
If all the gas solenoid valves are tight, the tightness control
forwards the OK enable signal to the automatic burner
control unit GFA. The pilot valve output of the automatic
burner control unit GFA opens the gas solenoid valves V1
and V2 simultane- ously. The burner starts.
V1: quick or slow opening valve with start rate.
V2: any.
V3: quick opening, nominal size is dependent on test
volume VPand inlet pressure pu, see page 34 (Project
planning information), but is at least DN 15.
PZ = External pressure switch DG for the comparison of
inlet pressure p
u
and interspace pressure p
z
TC 4
DG
PZ
p
u
2
V3
V1
V2
p
u
p
Z
V
P
TC 4
OK
GFA
1 2 3 4 5 6 7 8 9 10 11 12 13
PZ
V2
V3
 
V1
L1(+)
N(-)

TC ·Edition 07.14
19

ADD FURNACE CO.,LTD.
44 ซอยบรมราชชนนี 
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1 .1 .13 TC 4 in a multiple burner system with two
auxiliary valves for supply and discharge
Tightness control TC 4 checks the central shut-off valve V1,
auxiliary valves V2 and V3 and several burner valves for
tightness.
The test volume VPis supplied via the auxiliary valve V3.
The external pressure switch DG monitors the pressure be-
tween the gas solenoid valves V1, V2 and the burner
valves.
Once the tightness test has been carried out successfully,
TC 4 opens gas solenoid valve V1. The tightness control
forwards the OK enable signal simultaneously to the
automatic burner control units for the burner valves. The
burner valves open and the burners start.
Thanks to the relief line and auxiliary valve V2, the test
volume VPis discharged into the combustion chamber
or into a safe
V1: any.
V2 and V3: quick opening, nominal size is dependent on
test volume VPand inlet pressure pu, see page 34 (Project
plan-ning information), but is at least DN 15.
area.
TC 4
DG
PZ
p
u
2
V2
V1
pu
p
Z
V3
VP
TC 4
1 2 3 4 5 6 7 8 9 10 11 1213
PZ
OK
V2
V1
V3
L1(+)
N(-)

TC ·Edition 07.14
20

ADD FURNACE CO.,LTD.
44 ซอยบรมราชชนนี 
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https://www.add-furnace.com E-mail: [e-mail]
1 .1 .14 TC 4 in a multiple burner system with 3 valves
installed in series
Tightness control TC 4 checks the central shut-off valve V1
and the gas solenoid valve V2 for tightness.
Valve V2 can only be checked for tightness when the
pressure downstream of V2 approximately corresponds to
the atmospheric pressure. The gas solenoid valve VAS and
the pressure switch DGVAS are used to relieve the pressure.
The pressure switch must be adjusted in such a way so that
enough pres- sure is relieved and no air can get into the
pipework.
Once the start-
is checked. If the pressure downstream of V2 is correct,
the VAS closes and the tightness test is started.
Once the tightness test has been carried out successfully,
the tightness control TC 4 opens the main valves V1 and
V2 with the OK enable signal and enables the
downstream burner control units.
V1 and V2: quick or slow opening valves with start rate.
p
u
= Inlet pressure
V
P
= Test volume
TC 4
DG
PZ
p
u
2
V1
V2
pu
p
Z
VP
TC 4
1 2 3 4 5 6 7 8 9 10 11 12 13
PZ
k1
DG
VAS
OK
k1
V2
VAS K1
V1
L1(+)
N(-)
PZ
DG
VA
S
VA
S

TC ·Edition 07.14
21

ADD FURNACE CO.,LTD.
44 ซอยบรมราชชนนี 
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2 Certification
EU certified pursuant to
–Declaration of conformity (D, GB) –see
ww.docuthek.com
Elster Kromschröder Kromschröder, LBE Products
03 Valves and butterfly valves Tightness controls
TC (K OS Declaration of conformity) Type of
document: Certificate
–Tightness control TC is designed for applications pursuant
to EN 746.
Meets the requirements of the
–Low Voltage Directive (2006/95/EC) in conjunction
with the relevant standards.
–Electromagnetic Compatibility Directive
(2004/108/EC) in conjunction with the relevant
sections of IEC 801 relating to radiation, as well as EN
50093.
FM approved
TC 1, TC 2 and TC 3 for 120 V and 230 V,
TC 4 for 24 V, 120 V and 230 V
Factory Mutual Research Class: 7411 Safety overpressure
slam shut valves.
Designed for applications pursuant to NFPA 85 and
NFPA 86.
www.approvalguide.com
UL listed
TC 2 and TC 4 for 120 V
Standard: UL 353 Limit control.
Link to Underwriters Laboratories –www.ul.com Tools
(at
Directory enter company name
Gas Appliance Electric Accessories, Link to File:
JHYR.MH28048, ANSI/UL 353, “Limit Controls”
Gas Appliance Electric Accessories Certified for
Canada,
Link to File: JHYR7.MH28048, CSA-C22.2 No. 24,
“Temper- ature-Indicating and -Regulating Equipment”
AGA approved
Australian Gas Association, approval number:
4581 www.aga.asn.au/product_directory
AGA