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Baxi Potterton 8642216 Boiler Pressure Switch, Air Pressure Switch, Fan Proving Switch, APS Replacement

Name: Baxi Potterton 8642216 Boiler Pressure Switch, Air Pressure Switch, Fan Proving Switch, APS Replacement
Brand: Potterton
SKU: W-452197
Price: 153.80 GBP
Availability: InStock

Brand Potterton

SKU W-452197

Manufacturer part number: 642216
EAN: 5039177675082

£153.80

inc VAT£128.17 ex VAT

Express delivery: allow 1 to 2 working daysExpress

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Description

Product Overview

The Baxi Potterton 8642216 pressure switch is a boiler air pressure switch (often called an APS or fan proving switch) designed to confirm correct airflow before ignition. It helps your boiler run safely and reliably by ensuring the fan and flue system are operating as intended. Ideal for replacing a faulty or worn pressure switch to restore normal boiler performance.

Key Features

Airflow safety proving helps confirm fan operation before ignition for safer boiler running.
Direct replacement spare designed for straightforward swap-over when the original switch fails.
Reliable boiler operation helps reduce lockouts and ignition issues linked to poor air pressure detection.
Genuine-spec component supports correct fit and function when matching the MPN and boiler model.

Use Case / Application

Used inside compatible boilers as part of the air pressure safety circuit, this pressure switch monitors the pressure difference created by the fan. Suitable for domestic heating systems where the boiler requires airflow confirmation to operate.

Typical use cases include:

Replacing a failed fan proving switch during boiler servicing and repairs
Resolving boiler lockout or ignition prevention related to air pressure fault codes
Maintenance work in homes, flats, rented properties, and light commercial premises

Problem → Solution

Ideal for fixing boiler start-up and safety cut-out problems caused by a faulty air pressure switch, helping restore correct fan proving and dependable heating.

Product Specifications

Manufacturer – Baxi

Manufacturer Part Number (MPN) – 642216

EAN / Barcode – 5039177675082

Product Type – Boiler Air Pressure Switch (APS) / Fan Proving Switch

Typical Applications / Use Cases – Boiler spares and repairs, airflow proving circuit, fan and flue safety interlock

Why Buy from BHL

Baxi is a trusted manufacturer of heating components, with parts designed to keep boilers operating safely and efficiently. Choose the Baxi Potterton 8642216 pressure switch (Part Number 642216) for a dependable replacement that helps restore correct airflow proving. Buy online from BHL, a specialist online merchant trusted by thousands of satisfied customers online since 1998 with thousands of 5 star reviews. Enjoy competitive pricing, free* and fast UK delivery, and orders delivered with care from UK warehouses. *see our terms

Reviews

Buying guide: Boiler Spares

Boiler spares are replacement parts for gas, LPG and oil boilers: printed circuit boards, fans, gas valves, pumps, diverter valves, heat exchangers, sensors, pressure gauges, burners, electrodes, seals, casing panels and flue parts. Most are made for one manufacturer, and often for a narrow range of models, so identifying the boiler correctly matters more than anything else.

Identify the boiler first

Find the data badge, usually behind the front panel or under the controls cover. It shows the manufacturer, the model and the GC (Gas Council) number, a seven-digit reference for the exact appliance. Natural gas and LPG versions of the same boiler usually have different GC numbers, and parts can change between production runs, so the GC number and serial number are the safest way to match a part. The boiler's installation and servicing manual lists the parts for each model.

Part numbers and replacements

Search by the manufacturer's part number where you have it. Manufacturers sometimes replace a part with a newer version under a new number; only use a replacement that the manufacturer lists for your model. Some repairs need a kit rather than a single part, for example a part supplied with new seals or fixings.

Safety

By law, work on gas boilers and their gas parts must be carried out by a Gas Safe registered engineer qualified for that type of appliance; ask to see their ID card before work starts. Oil boilers should be worked on by a suitably qualified technician.

For thermostats and programmers, see heating controls.

Shop all Boiler Spares