BWT WS355 14L Standard Electronic Water Softener | 15mm Kit | Metered | Part G Compliant
14 Litre Resin 1–6 People 15mm Install Kit Included Metered Control Part G Compliant Free BWT Commissioning
The BWT WS355 is a compact, fully automatic metered water softener with a 14-litre resin capacity, designed and developed specifically for UK homes and plumbing systems. It removes the calcium and magnesium minerals responsible for limescale and scum by passing hard water through an ion exchange resin bed, delivering BWT Luxury Water throughout your home — softer on skin and hair, kinder to appliances, and gentler on surfaces. The WS355 is the standard-flow model in the BWT WS range and is supplied complete with a 15mm installation kit as standard, making it ideal for conventional gravity-fed and combi boiler systems.
Metered control means the unit regenerates only when the resin is exhausted based on actual water usage — not on a fixed timer — resulting in lower salt and water consumption compared to time-clock softeners. The AMECS (Advanced Memory Electronic Control System) retains all settings for up to 72 hours during a power failure. Supplied with a 5-year parts, 2-year on-site labour warranty and free BWT commissioning — a BWT engineer will visit your home to set up and commission the unit after installation.
Key Features
Technical Specifications
| Specification | WS355 Detail |
|---|---|
| Resin Volume | 14 litres |
| Dimensions (H × W × D) | 602mm × 270mm × 480mm |
| Household Size | 1–6 people |
| Min Flow Rate | 10 l/min |
| Service Flow Rate | 25 l/min |
| Peak Flow Rate | 30 l/min |
| Max Pressure | 5 bar |
| Min Pressure | 1.7 bar |
| Max Water Temperature | 49°C |
| Inlet / Outlet Connection | ¾" BSP |
| Drain Connection | ½" tube |
| Installation Kit Included | 15mm hoses and valves (standard gravity/combi systems) |
| Salt per Regeneration | 1.2–2.4 kg (min/max) |
| Salt Type | Tablet salt (up to 16 tablets) |
| Max Softened Water Capacity | 2500 litres |
| Electrical Supply | 220V AC / 12V DC (transformer included) |
| Regeneration Type | Metered — demand-initiated (AMECS) |
| Regeneration Direction | Upward flow |
| Memory Backup | Up to 72 hours during power failure |
| Colour | Blue & Grey |
| Warranty | 5 years parts / 2 years on-site labour |
| Building Regulations | Part G compliant |
| Brand | BWT |
Frequently Asked Questions
What is the difference between the WS355 and WS455?
The WS355 is the standard-flow model with a 14L resin capacity and 15mm installation kit — peak flow rate of 30 l/min. The WS455 is the hi-flow model with a 10L resin capacity and 22mm installation kit — peak flow rate of 50 l/min, making it better suited to power shower systems, unvented (Megaflow) systems, and modern high-pressure plumbing. If your system uses 22mm pipework or you have a high-flow demand, the WS455 is recommended over the WS355.
Does the softener need a separate drinking water supply?
Yes — Building Regulations (Part G) require that at least one tap in the property continues to supply unsoftened (hard) mains water for drinking. This is typically the kitchen cold tap. The water softener should be plumbed in on the inlet side, with a branch taken off before the softener to the kitchen cold drinking tap. The WS355 is Part G compliant when installed correctly with an unsoftened drinking tap as required.
How often does it regenerate and how long does it take?
The WS355 regenerates based on actual water consumption (metered) — typically every few days for an average household, but the exact interval depends on local water hardness and daily usage. Regeneration takes approximately 110 minutes and is typically set to occur at night during low-demand periods. The unit is programmed to the local water hardness level during commissioning.
Is free commissioning really free?
Yes — BWT offers a free @Home commissioning service with the WS355. After purchase and installation, you book a visit from a BWT-trained commissioning engineer who will set up the unit to your local water hardness, demonstrate operation, and answer any questions. This service is free and is available directly from BWT. The product must be registered with BWT within 100 days of purchase to activate the full @Home warranty and commissioning offer.
Original: $1,071.64
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$375.07More Images
BWT WS355 14L Standard Electronic Water Softener | 15mm Kit | Metered | Part G Compliant
14 Litre Resin 1–6 People 15mm Install Kit Included Metered Control Part G Compliant Free BWT Commissioning
The BWT WS355 is a compact, fully automatic metered water softener with a 14-litre resin capacity, designed and developed specifically for UK homes and plumbing systems. It removes the calcium and magnesium minerals responsible for limescale and scum by passing hard water through an ion exchange resin bed, delivering BWT Luxury Water throughout your home — softer on skin and hair, kinder to appliances, and gentler on surfaces. The WS355 is the standard-flow model in the BWT WS range and is supplied complete with a 15mm installation kit as standard, making it ideal for conventional gravity-fed and combi boiler systems.
Metered control means the unit regenerates only when the resin is exhausted based on actual water usage — not on a fixed timer — resulting in lower salt and water consumption compared to time-clock softeners. The AMECS (Advanced Memory Electronic Control System) retains all settings for up to 72 hours during a power failure. Supplied with a 5-year parts, 2-year on-site labour warranty and free BWT commissioning — a BWT engineer will visit your home to set up and commission the unit after installation.
Key Features
Technical Specifications
| Specification | WS355 Detail |
|---|---|
| Resin Volume | 14 litres |
| Dimensions (H × W × D) | 602mm × 270mm × 480mm |
| Household Size | 1–6 people |
| Min Flow Rate | 10 l/min |
| Service Flow Rate | 25 l/min |
| Peak Flow Rate | 30 l/min |
| Max Pressure | 5 bar |
| Min Pressure | 1.7 bar |
| Max Water Temperature | 49°C |
| Inlet / Outlet Connection | ¾" BSP |
| Drain Connection | ½" tube |
| Installation Kit Included | 15mm hoses and valves (standard gravity/combi systems) |
| Salt per Regeneration | 1.2–2.4 kg (min/max) |
| Salt Type | Tablet salt (up to 16 tablets) |
| Max Softened Water Capacity | 2500 litres |
| Electrical Supply | 220V AC / 12V DC (transformer included) |
| Regeneration Type | Metered — demand-initiated (AMECS) |
| Regeneration Direction | Upward flow |
| Memory Backup | Up to 72 hours during power failure |
| Colour | Blue & Grey |
| Warranty | 5 years parts / 2 years on-site labour |
| Building Regulations | Part G compliant |
| Brand | BWT |
Frequently Asked Questions
What is the difference between the WS355 and WS455?
The WS355 is the standard-flow model with a 14L resin capacity and 15mm installation kit — peak flow rate of 30 l/min. The WS455 is the hi-flow model with a 10L resin capacity and 22mm installation kit — peak flow rate of 50 l/min, making it better suited to power shower systems, unvented (Megaflow) systems, and modern high-pressure plumbing. If your system uses 22mm pipework or you have a high-flow demand, the WS455 is recommended over the WS355.
Does the softener need a separate drinking water supply?
Yes — Building Regulations (Part G) require that at least one tap in the property continues to supply unsoftened (hard) mains water for drinking. This is typically the kitchen cold tap. The water softener should be plumbed in on the inlet side, with a branch taken off before the softener to the kitchen cold drinking tap. The WS355 is Part G compliant when installed correctly with an unsoftened drinking tap as required.
How often does it regenerate and how long does it take?
The WS355 regenerates based on actual water consumption (metered) — typically every few days for an average household, but the exact interval depends on local water hardness and daily usage. Regeneration takes approximately 110 minutes and is typically set to occur at night during low-demand periods. The unit is programmed to the local water hardness level during commissioning.
Is free commissioning really free?
Yes — BWT offers a free @Home commissioning service with the WS355. After purchase and installation, you book a visit from a BWT-trained commissioning engineer who will set up the unit to your local water hardness, demonstrate operation, and answer any questions. This service is free and is available directly from BWT. The product must be registered with BWT within 100 days of purchase to activate the full @Home warranty and commissioning offer.
Product Information
Product Information
Shipping & Returns
Shipping & Returns
Description
14 Litre Resin 1–6 People 15mm Install Kit Included Metered Control Part G Compliant Free BWT Commissioning
The BWT WS355 is a compact, fully automatic metered water softener with a 14-litre resin capacity, designed and developed specifically for UK homes and plumbing systems. It removes the calcium and magnesium minerals responsible for limescale and scum by passing hard water through an ion exchange resin bed, delivering BWT Luxury Water throughout your home — softer on skin and hair, kinder to appliances, and gentler on surfaces. The WS355 is the standard-flow model in the BWT WS range and is supplied complete with a 15mm installation kit as standard, making it ideal for conventional gravity-fed and combi boiler systems.
Metered control means the unit regenerates only when the resin is exhausted based on actual water usage — not on a fixed timer — resulting in lower salt and water consumption compared to time-clock softeners. The AMECS (Advanced Memory Electronic Control System) retains all settings for up to 72 hours during a power failure. Supplied with a 5-year parts, 2-year on-site labour warranty and free BWT commissioning — a BWT engineer will visit your home to set up and commission the unit after installation.
Key Features
Technical Specifications
| Specification | WS355 Detail |
|---|---|
| Resin Volume | 14 litres |
| Dimensions (H × W × D) | 602mm × 270mm × 480mm |
| Household Size | 1–6 people |
| Min Flow Rate | 10 l/min |
| Service Flow Rate | 25 l/min |
| Peak Flow Rate | 30 l/min |
| Max Pressure | 5 bar |
| Min Pressure | 1.7 bar |
| Max Water Temperature | 49°C |
| Inlet / Outlet Connection | ¾" BSP |
| Drain Connection | ½" tube |
| Installation Kit Included | 15mm hoses and valves (standard gravity/combi systems) |
| Salt per Regeneration | 1.2–2.4 kg (min/max) |
| Salt Type | Tablet salt (up to 16 tablets) |
| Max Softened Water Capacity | 2500 litres |
| Electrical Supply | 220V AC / 12V DC (transformer included) |
| Regeneration Type | Metered — demand-initiated (AMECS) |
| Regeneration Direction | Upward flow |
| Memory Backup | Up to 72 hours during power failure |
| Colour | Blue & Grey |
| Warranty | 5 years parts / 2 years on-site labour |
| Building Regulations | Part G compliant |
| Brand | BWT |
Frequently Asked Questions
What is the difference between the WS355 and WS455?
The WS355 is the standard-flow model with a 14L resin capacity and 15mm installation kit — peak flow rate of 30 l/min. The WS455 is the hi-flow model with a 10L resin capacity and 22mm installation kit — peak flow rate of 50 l/min, making it better suited to power shower systems, unvented (Megaflow) systems, and modern high-pressure plumbing. If your system uses 22mm pipework or you have a high-flow demand, the WS455 is recommended over the WS355.
Does the softener need a separate drinking water supply?
Yes — Building Regulations (Part G) require that at least one tap in the property continues to supply unsoftened (hard) mains water for drinking. This is typically the kitchen cold tap. The water softener should be plumbed in on the inlet side, with a branch taken off before the softener to the kitchen cold drinking tap. The WS355 is Part G compliant when installed correctly with an unsoftened drinking tap as required.
How often does it regenerate and how long does it take?
The WS355 regenerates based on actual water consumption (metered) — typically every few days for an average household, but the exact interval depends on local water hardness and daily usage. Regeneration takes approximately 110 minutes and is typically set to occur at night during low-demand periods. The unit is programmed to the local water hardness level during commissioning.
Is free commissioning really free?
Yes — BWT offers a free @Home commissioning service with the WS355. After purchase and installation, you book a visit from a BWT-trained commissioning engineer who will set up the unit to your local water hardness, demonstrate operation, and answer any questions. This service is free and is available directly from BWT. The product must be registered with BWT within 100 days of purchase to activate the full @Home warranty and commissioning offer.
