The Telford Tempest Stainless Steel Slimline Indirect 125L Unvented Cylinder (TSMI125SL) is a vertical hot-water cylinder designed for homes needing an indirect system in a compact footprint. It stores up to 125 litres of hot water and uses a primary heating coil connected to a boiler, with an immersion heater providing an additional heat source. Its slimline body measures 470mm in diameter and 1050mm high.
Telford describes its stainless-steel unvented cylinders as being made in the UK from duplex stainless steel and supplied with a lifetime cylinder warranty, subject to terms and conditions. Retailer listings differ on the warranty details, so confirm the guarantee, servicing requirements, included components and exact product specifications with the seller and current manufacturer documentation before purchase.
125L Capacity
Indirect Unvented Cylinder
Slimline Vertical Design
Stainless Steel
At a Glance
Cylinder Type
Indirect Unvented
Telford Tempest Slimline
Capacity
125 litres
Model: TSMI125SL
Dimensions
1050 × 470mm
Height × diameter, as listed
Orientation
Vertical
Slimline cylinder format
Key Features
125-Litre Hot Water Storage
Provides 125 litres of stored hot water for a suitably sized household system. Have cylinder capacity assessed against household occupancy, hot-water use and the number of bathrooms and outlets.
Indirect Heating Design
The indirect design uses a primary coil connected to a compatible boiler or heating system to heat the stored water. Confirm the heat source, controls and system configuration with your installer.
Slimline Vertical Format
With a listed diameter of 470mm and height of 1050mm, the vertical slimline design may suit installations where floor space is limited. Check the full installation dimensions and access route before ordering.
Stainless-Steel Construction
The cylinder is listed as stainless steel. Telford describes its stainless-steel unvented range as manufactured from duplex stainless steel; check the model-specific product datasheet for precise material details.
Unvented Mains-Pressure System
Designed for an unvented hot-water system. Confirm that the available water supply, operating conditions, safety components and installation space are suitable for the cylinder and property.
Warranty and Servicing
Telford advertises a lifetime warranty on its stainless-steel cylinder range, subject to terms and conditions. Warranty coverage may depend on registration and servicing; confirm the exact terms for TSMI125SL with the seller and manufacturer.
Important Installation Guidance:
This is an unvented hot-water cylinder. Installation, commissioning and servicing should be carried out by a suitably qualified person in accordance with the manufacturer’s instructions and applicable regulations. Ask the installer to confirm system suitability, connections, safety components, electrical requirements, access and ongoing service requirements.
Key Specifications
| Product |
Telford Tempest Stainless Steel Slimline Indirect 125L Unvented Cylinder |
| Model Number |
TSMI125SL |
| Range |
Tempest Slimline |
| Capacity |
125 litres |
| Cylinder Type |
Indirect unvented |
| Orientation |
Vertical |
| Height |
1050mm |
| Diameter |
470mm |
| Cylinder Material |
Stainless steel; confirm exact grade in the model datasheet |
| Colour |
White |
| Connection Size |
Confirm connection sizes in the manufacturer’s datasheet; retailer listings may contain inconsistent information |
| Warranty |
Manufacturer advertises a lifetime cylinder warranty, subject to terms and conditions; confirm model-specific coverage |
Frequently Asked Questions
Is the TSMI125SL an indirect cylinder?
Yes. The TSMI125SL is listed as an indirect unvented cylinder. Its primary coil is designed to transfer heat from a compatible heating system to the stored water.
What are the dimensions of this 125L cylinder?
Retailer specifications list the cylinder at 1050mm high and 470mm in diameter. Check the latest manufacturer datasheet for installation clearances and connection positions before purchase.
What is the warranty on the Telford Tempest cylinder?
Telford advertises a lifetime warranty on its stainless-steel cylinder range, subject to terms and conditions. Confirm the exact warranty for this model, including servicing and registration requirements, with the seller or manufacturer.
The Telford Tempest TSMI125SL is a 125-litre slimline indirect unvented cylinder with a vertical design and stainless-steel construction. Check the model-specific datasheet, connection details and warranty terms, and have a qualified installer confirm it is suitable for your hot-water system before ordering.
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