HTS KS – Tightness Controls TC

Overview

The Kromschröder Tightness Control TC is an electronic valve proving system (VPS) that checks the leak-tight closure of both gas safety valves before each burner start-up, after each shut-down, or both — depending on configuration. By verifying valve integrity and blocking burner ignition on any detected leak, the TC provides an additional layer of combustion safety for industrial and commercial gas-fired systems.

The TC series includes models for direct attachment to valVario solenoid valves (TC 1V), combination controls CG (TC 1C), and universal versions for quick or slow opening individual valves (TC 2, TC 3). All models are rated for use in safety functions up to SIL 3 in accordance with EN 61508 and PL e per ISO 13849, and carry EU Gas Appliances Regulation (EU) 2016/426 and AGA approvals.

Features & Benefits

• Adjustable measurement time (tM) from 5 to 30 seconds — adapts sensitivity to system-specific leakage rate requirements
• Selectable test instant — test before burner run (Mode 1), after burner run (Mode 2), or both (Mode 3) via DIP switches
• Self-monitoring electronics — non-volatile fault lock-out prevents reset without resolving the detected fault
• Tri-color LED status indicators — separate LEDs for each valve (V1, V2) display tight, untested, testing, or leaking status at a glance
• Remote reset capability — reset via button on device or by applying control voltage to terminal 11
• Wide voltage compatibility — available in 230 V AC, 120 V AC, and 24 V DC versions for mains and control voltage
• IP 65 enclosure — suitable for industrial environments with housing made of impact-resistant plastic
• SIL 3 / PL e rated — designed lifetime of 250,000 switching cycles or 10 years, per EN 13611
• Certified to EU Gas Appliances Regulation (EU) 2016/426 (GAR), LVD, EMC, RoHS, EN 1643, EN 60730-2-5, and EN 61508
• AGA approved — Australian Gas Association Approval No. 8618

Technical Specifications

• Inlet pressure (pu): 10 to 500 mbar (3.9 to 195 “WC)
• Mains & control voltage: 230 V AC ±15/+10%, 50/60 Hz; 120 V AC -15/+10%, 50/60 Hz; 24 V DC ±20%
• Power consumption: 5.5 W at 120/230 V AC; 2 W at 24 V DC (TC 3 adds 8 VA for auxiliary valve)
• Valve opening time (tL): 3 seconds (fixed)
• Measurement time (tM): 5 to 30 seconds, adjustable (factory setting: 30 s)
• Max. load current — safety interlock/valve outputs: 3 A resistive at 120/230 V AC; 5 A resistive at 24 V DC
• Fault signal output: max. 5 A at 24 V DC, 120 V AC, or 230 V AC
• Fusing: 5 A slow-acting, H, 250 V per IEC 60127-2/5 (F1 and F2)
• Cable connections: 5 × M16 × 1.5 cable glands; cable cross-section 0.75–2.5 mm² (AWG 19–14)
• Diagnostic coverage (DC): 91.4% at 120/230 V AC; 91.5% at 24 V DC
• PFHD: 17.3 × 10⁻⁹ 1/h at 120/230 V AC; 17.5 × 10⁻⁹ 1/h at 24 V DC
• Safe Failure Fraction (SFF): 97.5%
• Designed lifetime: 250,000 switching cycles or 10 years (per EN 13611)
• Ambient temperature: -20 to +60°C (-4 to +140°F), no condensation
• Storage/transport temperature: -20 to +40°C (-4 to +104°F)
• Max. installation height: 2,000 m AMSL
• Enclosure: IP 65
• Gas types: natural gas, LPG (gaseous), biogas (max. 0.1%-by-vol. H₂S), clean air
• TC 1V weight: 215 g (0.47 lbs); TC 2 with adapter: 260 g (0.57 lbs); TC 3: 420 g (0.92 lbs)

Applications

• Industrial thermoprocessing equipment requiring valve proving per ISO 13577-2 or EN 746-2
• Industrial and commercial boilers with two safety shut-off valves
• Forced draught burners subject to EN 676 tightness control requirements
• Systems over 1,200 kW capacity where tightness controls are mandated by EN 746-2, EN 676, or ISO 13577-2
• NFPA 86 applications from 117 kW (400,000 Btu/h) in conjunction with a visual indicator
• Multiple burner systems with centralized safety shut-off valves
• Systems with slow opening motorized valves (VK) up to DN 65, directly flanged together (TC 2, TC 3)
• Safety functions requiring SIL 3 / PL e combustion valve proving

Models / Configurations

• TC 1V – Directly flange-mounts to all valVario controls (VAS, VCx); one universal version fits all valve sizes. Pipe connection: Rp internal thread (R) or NPT internal thread (N). Available in 230 V AC (W/W), 120 V AC (Q/Q), and 24 V DC (K/K).
• TC 1C – For combination controls CG 1 to 3; adapter plate included for installation. Pipe connection: Rp (R) or NPT (N). Available in 230 V AC (W/W), 120 V AC (Q/Q), and 24 V DC (K/K). Note: measurement time tM must be set to 5 s for all CG versions.
• TC 2 – Universal version for quick or slow opening gas solenoid valves of any nominal size (with start rate); adapter plate included. Supports auxiliary valves for pneumatically operated or slow opening valves without start rate. Pipe connection: Rp (R) or NPT (N). Available in 230 V AC (W/W), 120 V AC (Q/Q), and 24 V DC (K/K).
• TC 3 – Universal version for quick and slow opening solenoid valves and motorized valves of any nominal size; tightness test performed with valves installed in the TC 3. Pipe connection: Rp (R) or NPT (N). Available in 230 V AC (W/W), 120 V AC (Q/Q), and 24 V DC (K/K).

Order example: TC 1V05W/W — TC 1V, max. 500 mbar inlet pressure, 230 V AC mains/control voltage.

TC Tightness Control Accessories

• Socket — Order No. 74916715 – Standard 3-pin + PE socket, black; for electrical connection of TC to valves with a plug connector.
• Valve Connection Cable — Order No. 74960689 – Standard 3-pin + PE socket, black, with 4-core electrical cable, 0.45 m length; for direct valve wiring.

Documentation