Vaillant
Vaillant Non Return Valve 0020236856
Vaillant non-return valve in the 1 1/4 inch version, part number 0020236856, for use on compatible unvented cylinders.
At a glance
- Also known as 1386970
£52.57
£43.81 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 Vaillant 0020236856 is a non-return valve supplied in the 1 1/4 inch version. It is fitted to compatible Vaillant unvented hot water cylinders, where it prevents reverse flow through the connected pipework. The valve forms part of the cylinder's hydraulic assembly and is matched to the appliance family listed below.
Signs this part needs replacing
- Water passing back through the valve when flow should be stopped
- Gravity circulation or heat migration through the cylinder pipework when the system is idle
- The cylinder losing its stored heat overnight without a call for hot water
- Water hammer, chatter or knocking from the valve under flow
- Visible leakage or weeping from the valve body or its connections
Before you order
- Confirm your cylinder model against the fit list above before ordering
- Check that the existing valve is the 1 1/4 inch version, as other sizes are not covered by this part number
- Verify the part number 0020236856 against the manufacturer's parts list for your appliance
- Inspect the surrounding pipework and connections for condition before fitting
Compliance
| Alternative numbers | 1386970 |
|---|
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| VAILLANT VANTAGE VIH SW GB 500 BES | — | — | — | |
| VAILLANT VIH SW GB 500 BES | — | — | — |
Documents & drawings
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