Viessmann 7837231 Expansion Vessel | Replacement Spare Part
- SKU
- EDDVIESSMANNSPARE03
Need something else?
Can’t find what you’re looking for? Click here to use our spare part finder.Viessmann 7837231 Expansion Vessel
The Viessmann 7837231 is a genuine expansion vessel designed to regulate pressure within Viessmann boiler systems by absorbing the natural expansion of water as it heats. This component is essential for maintaining stable operating pressure and protecting the boiler and heating system from excessive stress.
In a sealed heating system, water expands as its temperature rises. Without a mechanism to accommodate this increase in volume, system pressure would rise rapidly, potentially triggering the pressure relief valve or causing damage to internal components. The expansion vessel prevents this by incorporating an internal diaphragm that separates system water from a pre-charged air chamber. As pressure increases, the diaphragm flexes, allowing the vessel to safely absorb the excess volume.
Manufactured to precise OEM standards, the 7837231 expansion vessel is designed for durability under repeated pressure cycles and temperature fluctuations. However, over time, the internal diaphragm can weaken or fail, or the air charge can be lost. When this happens, the vessel can no longer effectively absorb expansion, leading to symptoms such as pressure spikes, frequent topping up, or discharge from the safety relief valve.
Replacing a faulty expansion vessel restores proper pressure control, improves system stability, and helps prevent unnecessary wear on other components within the heating system.
Key Features:
Part Number: 7837231
Type: Expansion vessel / pressure compensation tank
Function: Absorbs thermal expansion and stabilises system pressure
Genuine Viessmann spare part – manufactured to OEM specification
Internal diaphragm design for reliable operation
Reduces pressure fluctuations and system stress
Must be fitted by a qualified Gas Safe registered engineer
Compatible Boilers Include:
Used across selected Viessmann boiler models, including:
Viessmann Vitodens range (model dependent)
Other Viessmann sealed system boilers
Viessmann provide a 1 year warranty on all spare parts. Electrical Deals Direct now sells a wide range of spare parts. If you cannot see the item you require on our website, please call 01934 253600 or email [email protected] for more information.
| MPN | 7837231 |
|---|---|
| Product Code | EDDVIESSMANNSPARE03 |
| Compatible With: Product Code (SKU) | Viessmann Vitodens 050-W; Vitodens 100-W WB1C/B1KA/BPJA 19-35kW Combi & System |
| Part Origin | Compatible |
| Part or Accessory? | Part |
| Brand | Viessmann |
| Full Weight (kG) | .5 |
Delivery Information -
Standard delivery for all orders over £150 ex-VAT are free of charge.
If we can speed this up, we will, but you can also select Express Delivery when you check out and get your purchase more quickly (usually the next working day, subject to a 1pm cut-off): there is an extra charge for this ranging from £5 to £29.99 depending on the products you are buying.
We partner with several of the best UK carriers (such as TNT, Royal Mail, DPD etc) depending on the type of product and the warehouse it is coming from, and also with some pallet companies for larger items. All of these operate during normal Monday – Friday working hours, and we expect all deliveries to arrive in 5 days. For more details checkout this page.
Gledhill Cylinders – Delivery Charge -
For all Gledhill Cylinders, a flat delivery charge of £33.00 (ex-VAT) applies, regardless of order value or delivery method. This will be added automatically at checkout.
Returns Information -
Having to return a product because it doesn’t fit, or is not what you wanted, is really annoying! To try and make sure this isn’t necessary we have lots of helpful advice on our site, and you should feel free to call our experts on the number above to check if you are in any doubt at all – we’re always happy to help.
But if you do, don’t worry, just contact us and we’ll get it sorted (note that for trade customers there may be a restocking fee). If you need it, we can usually arrange the carrier to pick it up.
For full details of our policy, check out the small print here.
Viessmann 7837231 Expansion Vessel
The Viessmann 7837231 is a genuine expansion vessel designed to regulate pressure within Viessmann boiler systems by absorbing the natural expansion of water as it heats. This component is essential for maintaining stable operating pressure and protecting the boiler and heating system from excessive stress.
In a sealed heating system, water expands as its temperature rises. Without a mechanism to accommodate this increase in volume, system pressure would rise rapidly, potentially triggering the pressure relief valve or causing damage to internal components. The expansion vessel prevents this by incorporating an internal diaphragm that separates system water from a pre-charged air chamber. As pressure increases, the diaphragm flexes, allowing the vessel to safely absorb the excess volume.
Manufactured to precise OEM standards, the 7837231 expansion vessel is designed for durability under repeated pressure cycles and temperature fluctuations. However, over time, the internal diaphragm can weaken or fail, or the air charge can be lost. When this happens, the vessel can no longer effectively absorb expansion, leading to symptoms such as pressure spikes, frequent topping up, or discharge from the safety relief valve.
Replacing a faulty expansion vessel restores proper pressure control, improves system stability, and helps prevent unnecessary wear on other components within the heating system.
Key Features:
Part Number: 7837231
Type: Expansion vessel / pressure compensation tank
Function: Absorbs thermal expansion and stabilises system pressure
Genuine Viessmann spare part – manufactured to OEM specification
Internal diaphragm design for reliable operation
Reduces pressure fluctuations and system stress
Must be fitted by a qualified Gas Safe registered engineer
Compatible Boilers Include:
Used across selected Viessmann boiler models, including:
Viessmann Vitodens range (model dependent)
Other Viessmann sealed system boilers
Viessmann provide a 1 year warranty on all spare parts. Electrical Deals Direct now sells a wide range of spare parts. If you cannot see the item you require on our website, please call 01934 253600 or email [email protected] for more information.
| MPN | 7837231 |
|---|---|
| Product Code | EDDVIESSMANNSPARE03 |
| Compatible With: Product Code (SKU) | Viessmann Vitodens 050-W; Vitodens 100-W WB1C/B1KA/BPJA 19-35kW Combi & System |
| Part Origin | Compatible |
| Part or Accessory? | Part |
| Brand | Viessmann |
| Full Weight (kG) | .5 |
Delivery Information -
Standard delivery for all orders over £150 ex-VAT are free of charge.
If we can speed this up, we will, but you can also select Express Delivery when you check out and get your purchase more quickly (usually the next working day, subject to a 1pm cut-off): there is an extra charge for this ranging from £5 to £29.99 depending on the products you are buying.
We partner with several of the best UK carriers (such as TNT, Royal Mail, DPD etc) depending on the type of product and the warehouse it is coming from, and also with some pallet companies for larger items. All of these operate during normal Monday – Friday working hours, and we expect all deliveries to arrive in 5 days. For more details checkout this page.
Gledhill Cylinders – Delivery Charge -
For all Gledhill Cylinders, a flat delivery charge of £33.00 (ex-VAT) applies, regardless of order value or delivery method. This will be added automatically at checkout.
Returns Information -
Having to return a product because it doesn’t fit, or is not what you wanted, is really annoying! To try and make sure this isn’t necessary we have lots of helpful advice on our site, and you should feel free to call our experts on the number above to check if you are in any doubt at all – we’re always happy to help.
But if you do, don’t worry, just contact us and we’ll get it sorted (note that for trade customers there may be a restocking fee). If you need it, we can usually arrange the carrier to pick it up.
For full details of our policy, check out the small print here.
Let us call you
Leave your details and a member of our team will call you back.
Thanks — we've got it!
One of the team will call you back shortly.
- Price:
- Actual Price: