Telford Tempest Indirect Horizontal Heat Pump Cylinders

The Telford Tempest Indirect Horizontal Heat Pump Cylinder range (models TSMI170H/HP, TSMI200H/HP, TSMI250H/HP and TSMI300H/HP) consists of Duplex stainless‑steel, unvented, horizontal hot‑water cylinders with internal heat‑pump coils, designed for height‑restricted installations while still delivering mains‑pressure hot water.

Key Features

• Horizontal unvented design – low‑profile cylinders mounted on cradles, ideal for lofts, under‑stairs areas or plant spaces with limited headroom while supplying high‑flow, mains‑pressure hot water.
• Heat‑pump optimised coil – internal coil sized specifically for low‑temperature heat pumps to maximise heat transfer and support fast, efficient cylinder reheat.
• Duplex stainless‑steel construction – highly corrosion‑resistant stainless‑steel vessel and coil for long service life, combined with high‑performance insulation to minimise standing heat losses.
• External expansion vessel – supplied with a remote expansion vessel and wall‑mounting bracket to simplify installation and servicing.
• Factory‑fitted immersion heater – 3kW immersion heater provides backup heat and supports legionella protection or off‑peak heating strategies.
• Complete unvented kit – typically supplied with temperature and pressure relief valve, inlet control group, tundish and motorised valve to form a compliant unvented installation when fitted by a competent installer.

Variant Overview

• TSMI170H/HP – 170L Horizontal HP Cylinder
  Compact 170L horizontal heat‑pump cylinder aimed at smaller dwellings or low hot‑water demand, offering the same Tempest construction and unvented components as larger models in a reduced footprint.
• TSMI200H/HP – 200L Horizontal HP Cylinder
  Mid‑sized 200L horizontal cylinder providing a balance of storage capacity and space efficiency, well suited to typical small to medium homes with restricted vertical space.
• TSMI250H/HP – 250L Horizontal HP Cylinder
  Larger 250L horizontal unit for medium properties with higher DHW usage, retaining the horizontal cradle‑mounted format and heat‑pump‑optimised coil for efficient operation.
• TSMI300H/HP – 300L Horizontal HP Cylinder
  300L horizontal cylinder designed for bigger homes or multi‑bath properties, combining generous storage volume with a low‑height form factor.

Construction & Performance

• Capacities: nominal 170L, 200L, 250L and 300L across the range, all from the Tempest Heat Pump Horizontal family.
• Orientation & supports: designed exclusively for horizontal installation on the supplied cradle supports to ensure correct loading and connection alignment.
• Operating conditions: unvented mains‑pressure cylinders with typical maximum working pressure around 3 bar, T&P valve set at standard unvented values (commonly 7 bar / 90°C), and thick factory‑applied insulation to reduce heat loss.

Applications & Use Cases

• Heat‑pump systems: intended for use with air‑to‑water or ground‑source heat pumps as the primary heat source, using the dedicated internal heat‑pump coil.
• Height‑restricted plant rooms: ideal where a vertical cylinder cannot be accommodated, such as low loft spaces, eaves cupboards, or above other plant in tight utility rooms.
• Mains‑pressure domestic hot water: delivers high‑flow, mains‑pressure hot water to modern bathrooms and multiple outlets when installed with the supplied unvented kit and appropriate controls.