Baxi
Baxi 5114691 Potterton & Main CIMM RP250 8 Litre Expansion Vessel
Baxi 5114691 8 litre expansion vessel for Baxi heating appliances, absorbing system water expansion to hold pressure steady.
At a glance
- Part type: Expansion vessel (hydraulics)
- Also known as EXPANSION-VESSEL-8LTR-3-BAR-34
£72.00
£60.00 ex. VAT · VAT at 20%
Same-day dispatch
Ordered by 4pm Mon–Fri, 10:30am Sat.
30-day returns
Unused, in original packaging.
What it is
The Baxi 5114691 is an 8 litre expansion vessel from Baxi's hydraulics range. It is a sealed diaphragm vessel that absorbs the volume increase of system water as it heats, keeping pressure within the working range and limiting strain on the pressure relief valve and other hydraulic components. It is a direct replacement item for the vessel originally fitted to the appliance.
Signs this part needs replacing
- System pressure climbs sharply once the appliance is up to temperature, then falls back when cold
- The pressure relief valve discharges water during normal heating cycles
- Water weeps from the air valve on the vessel when its cap is removed
- The vessel feels heavy or full of water when shaken, indicating a failed diaphragm
- Pressure has to be topped up repeatedly, or the appliance locks out on low pressure soon after filling
Before you order
- Check the part number 5114691 against the data badge or manual for your appliance
- Compare the physical size, connection thread and mounting bracket of the failed vessel with the replacement
- On a sealed system, check the vessel's air charge and re-pressurise the system after fitting
Mechanical
| Part type | 8Ltr Expansion Vessel |
|---|
Compliance
| Manufacturer part number (MPN) | 5114691 |
|---|---|
| GPC classification | Household Boilers/Furnaces/Tank Water Heaters Replacement Parts/Accessories |
| Alternative numbers | EXPANSION-VESSEL-8LTR-3-BAR-34 |
No fitment data held for this part.
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