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Baxi Expansion Vessel 7L 7683801
IN STOCK
FROM £70.00
Baxi Boiler Expansion Vessel 7L 7683801
Product Overview
The Baxi Boiler Expansion Vessel 7L (Part Number: 7683801) is a replacement expansion vessel assembly designed for use within selected Baxi heating systems.
The expansion vessel is an important component of a sealed heating system. It accommodates the increase in water volume that occurs as the heating system heats up, helping to control pressure changes and maintain stable system operation.
The 7683801 is a 7-litre expansion vessel assembly and is supplied as a complete vessel assembly rather than a repair kit. Baxi documentation also identifies 7683801 as an expansion vessel spare part.
ℹ️ Product Condition Options:
This part may be available in New or Refurbished condition. Please check the available options from the dropdown menu.
Technical Insight & Common Failure Symptoms
An expansion vessel contains an internal diaphragm separating the heating system water from a pressurised air or gas chamber. As the system water heats and expands, the vessel provides space for this expansion, helping to prevent excessive increases in system pressure.
Over time, an expansion vessel may lose its charge or the internal diaphragm may deteriorate, reducing its ability to manage pressure correctly.
Typical symptoms associated with an expansion vessel requiring replacement or servicing include:
- Boiler pressure rising significantly when the heating is operating
- Frequent pressure loss from the heating system
- Frequent need to repressurise the boiler
- Pressure relief valve discharging water
- Large fluctuations in system pressure
- Expansion vessel losing its ability to absorb thermal expansion
A correctly sized and functioning expansion vessel helps maintain stable pressure and reliable operation of the sealed heating system.
Technical Specifications
- Manufacturer: Baxi
- Manufacturer Part Number (MPN): 7683801
- Type: Expansion Vessel Assembly
- Capacity: 7 Litres
- Pack Quantity: 1
The 7-litre capacity and part number 7683801 are confirmed by Baxi parts documentation and UK boiler-spares suppliers.
Compatibility
This part is designed for selected models within the Baxi range and is also used under the same manufacturer part number in selected Main and Potterton applications.
Please strictly verify the manufacturer part number 7683801 against your boiler's technical manual, exploded parts diagram, or existing expansion vessel before ordering to guarantee correct fitment.
Safety Advice
Expansion vessels form part of a sealed heating system and operate under pressure. Installation, replacement, pressure adjustment, and boiler servicing should only be carried out by a suitably qualified heating engineer in accordance with the manufacturer's instructions and applicable UK safety regulations.
This part fits the following boilers:
Fits Appliance(s)
GC No.
Baxi 624 Combi
Baxi 630 Combi
Baxi 636 Combi
Baxi 818 System
Baxi 824 System
Baxi 825 Combi
Baxi 830 Combi
Baxi 836 Combi
Main Eco Compact 15 System
Main Eco Compact 18 System
Main Eco Compact 25 Combi
Main Eco Compact 30 Combi
Potterton Combi 25
Potterton Combi 25 LPG
Potterton Combi 30
Potterton Combi 30 LPG
Potterton Combi 36
Potterton System 12
Potterton System 15
Potterton System 18
Potterton System 18 LPG
Potterton System 24
Potterton System 24 LPG
47-077-28
47-077-29
47-077-30
41-470-73
41-470-74
47-077-38
47-077-39
47-077-40
41-467-30
41-467-31
47-467-14
47-467-15
47-393-58
47-393-70
47-393-59
47-393-69
47-393-67
41-594-12
41-592-54
41-592-55
41-592-96
41-594-13
41-594-16
Delivery
Free next day UK delivery is available on orders over £50.
Orders placed before 3 PM are usually dispatched the same working day.
Delivery times may vary for remote areas, Highlands, islands, and non-mainland UK destinations.
If you need urgent delivery help, please contact our customer service team before placing your order.
All Orders First 30 Days:
You can return or cancel your orders for any reason at any time within 30 days of receipt. After 30 days, we reserve the right to charge a restocking fee or refuse the return.
Parts must be returned in the same condition and packaging as received, or we may deduct a percentage of the cost of the part.
A full refund or exchange will be agreed once the item(s) have been received and inspected to ensure they are unused and in their original packaging where applicable.
If the part is returned as faulty and is found to be working upon inspection, postage costs will be deducted from the refund.
Faulty Items After 30 Days:
All items come with a 1 year HTS warranty from the date of purchase. Warranty means HTS will repair or replace the item.
Refunds:
Our returns team will process your refund after we receive and check your items. Please allow up to 15 days for your refund to be processed.
The refund will be made to the original payment method used to place the order.
Contact Us:
For any queries, email us at returns@heatingtradesupplies.com or call +44 01912633708.
Customer Services
National Boiler Spares Ltd
Tyne View Terrace
Wallsend
Tyne and Wear
NE28 6SG
