400L Indirect Telford Tempest Vertical Unvented Cylinder TSMI400

400L Indirect Telford Tempest Vertical Unvented Cylinder – TSMI400

The 400L Telford Tempest TSMI400 is a high-capacity indirect vertical unvented hot water cylinder, designed for large residential properties, luxury homes and light commercial applications where exceptional hot water performance is essential.

With a generous 400-litre capacity, the TSMI400 is ideal for properties with multiple bathrooms, high occupancy levels or periods of heavy hot water usage. Manufactured from 2304 Duplex Stainless Steel, it offers exceptional corrosion resistance, outstanding durability and rapid hot water recovery when connected to a traditional boiler. The integrated 3kW immersion heater provides reliable backup hot water whenever required.

Supplied complete with the expansion vessel and installation kit, the TSMI400 includes everything required for a professional installation.

Key Features

• 400 litre indirect vertical unvented cylinder
• Ideal for large homes, luxury properties and light commercial applications
• Manufactured from 2304 Duplex Stainless Steel
• Excellent corrosion resistance for a longer service life
• 3 Bar working pressure
• Pressure tested to 15 Bar
• Relief valve operates at 7 Bar / 90–95°C
• High-performance mains pressure hot water
• Rapid hot water recovery
• 1" Female BSP connections
• Suitable for traditional boiler systems
• Complete with expansion vessel and installation kit
• Lifetime cylinder warranty*

Technical Specification

Supplied Complete With

• Expansion Vessel
• Expansion Vessel Kit
• Dual High Limit Thermostat
• 3kW Immersion Heater (240V Single Phase)
• Temperature & Pressure Relief Valve
• 3 Bar Inlet Control Group
• Two Port Motorised Valve

Everything required for a standard installation is included.

Why Buy From TDL?

• Kept in stock for fast dispatch
• FREE Delivery (typically 1-2 working days)
• Competitive UK prices
• Expert technical advice before and after your purchase
• Real People. Real Service. For Over 40 Years.

Ideal Applications

The 400L Telford Tempest is recommended for:

• Large family homes
• Luxury properties with multiple bathrooms
• Homes with high daily hot water demand
• Annexes and multi-generational households
• Light commercial properties
• Guest houses and small hospitality settings

Warranty

• Lifetime warranty on the stainless steel cylinder*
• 2-year warranty on supplied components

The cylinder must be serviced every 12 months by a qualified engineer to maintain the manufacturer's warranty.