Vaillant
Vaillant Insulation 24mm 0020252122
Vaillant 24mm insulation for Etec Plus, Etec Pro and Etec Sustain gas boilers, fitted as casing insulation.
At a glance
- Part type: insulation
- Also known as 1388538
Showing prices
£76.24
£63.53 ex. VAT · VAT at 20%
Available to order · 1 working day
Available to order · 1 working day
Not certain it's the right part? The technical team verifies fitment before dispatch — no charge, and it stops a second trip.Call the technical teamSend a technical question
Same-day dispatch
Ordered by 4pm Mon–Fri, 10:30am Sat.
30-day returns
Unused, in original packaging.
What it is
This is a 24mm insulation component manufactured by Vaillant for its Etec Plus, Etec Pro and Etec Sustain gas boiler ranges. It is supplied as a casing part and sits within the boiler's insulated casing assembly, where it limits heat loss from the appliance and helps maintain stable internal operating temperatures.
Signs this part needs replacing
- Visible crumbling, flaking or breakdown of the insulation material
- Discolouration, scorching or charring on the insulation surface
- Insulation that has become detached, compressed or displaced from its casing position
- Increased casing surface temperature or noticeable heat loss around the boiler
- Insulation damaged during previous servicing or component access
Before you order
- Confirm your boiler's model and variant against the fitment list above
- Check the existing insulation for the 24mm thickness and part number 0020252122
- Inspect the casing assembly for any other damaged insulation sections that may also need attention
- Verify the appliance is a Vaillant Etec Plus, Etec Pro or Etec Sustain unit before ordering
Compliance
| Alternative numbers | 1388538 |
|---|
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| VAILLANT VU 126/5-5 R6 | 41-694-20 | 41-694-20 | — | — |
| VAILLANT VU 156/5-5 R6 | 41-694-21 | 41-694-21 | — | — |
| VAILLANT VU 186/5-5 R6 | 41-694-22 | 41-694-22 | — | — |
| VAILLANT VU 186/5-5 R6 LPG | 41-694-23 | 41-694-23 | — | — |
| VAILLANT VU 246/5-5 R6 | 41-694-24 | 41-694-24 | — | — |
| VAILLANT VU 306/5-5 R6 | 41-694-25 | 41-694-25 | — | — |
| VAILLANT VU 306/5-5 R6 LPG | 41-694-26 | 41-694-26 | — | — |
| VAILLANT VU 386/5-5 R6 | 41-694-27 | 41-694-27 | — | — |
| VAILLANT VU 446/5-5 | 41-694-28 | 41-694-28 | — | — |
| VAILLANT VU 606/5-5 | 41-694-29 | 41-694-29 | — | — |
Showing 10 of 58 compatible appliances.
Fitment listings are a guide, not a guarantee. Plant-room assemblies get modified on site more often than not. Send us the GC number off the data badge and a photo of the existing valve and we will confirm before anything is dispatched.
Documents & drawings
Everything we hold for this part. Where a document exists but we don't hold it, the technical team will source it from the manufacturer — usually the same working day.
manual
VAILLANT appliance manual — VU 126/5-5 R6 (GC 41-694-20), VU 156/5-5 R6 (GC 41-694-21), VU 186/5-5 R6 (GC 41-694-22), VU 186/5-5 R6 LPG (GC 41-694-23), VU 246/5-5 R6 (GC 41-694-24), VU 306/5-5 R6 (GC 41-694-25), VU 306/5-5 R6 LPG (GC 41-694-26), VU 386/5-5 R6 (GC 41-694-27), VUW 196/5-5 R6 (GC 47-044-83), VUW 246/5-5 R6 (GC 47-044-84), VUW 246/5-5 R6 LPG (GC 47-044-85), VUW 286/5-5 R6 (GC 47-044-86), VUW 306/5-5 R6 (GC 47-044-82), ecoTEC PLUS 612 VU 126/5-5 R6 (2017) (GC 41-694-20), ecoTEC PLUS 615 VU 156/5-5 R6 (2017) (GC 41-694-21), ecoTEC PLUS 618 VU 186/5-5 R6 (2017) (GC 41-694-22), ecoTEC PLUS 618 VU 186/5-5 R6 LPG (2017) (GC 41-694-23), ecoTEC PLUS 624 VU 246/5-5 R6 (2017) (GC 41-694-24), ecoTEC PLUS 630 VU 306/5-5 R6 (2017) (GC 41-694-25), ecoTEC PLUS 630 VU 306/5-5 R6 LPG (2017) (GC 41-694-26), ecoTEC PLUS 637 VU 386/5-5 R6 (2017) (GC 41-694-27), ecoTEC PLUS 825 VUW 196/5-5 R6 (2017) (GC 47-044-83), ecoTEC PLUS 832 VUW 246/5-5 R6 (2017) (GC 47-044-84), ecoTEC PLUS 832 VUW 246/5-5 R6 LPG (2017) (GC 47-044-85), ecoTEC PLUS 835 VUW 306/5-5 R6 (2017) (GC 47-044-82), ecoTEC PLUS 838 VUW 286/5-5 R6 (2017) (GC 47-044-86)
manualmanualVAILLANT appliance manual — VU 446/5-5 (GC 41-694-28), VU 606/5-5 (GC 41-694-29), ecoTEC VU 446/5-5 (2018) (GC 41-694-28), ecoTEC VU 606/5-5 (2018) (GC 41-694-29)
manualmanualVAILLANT appliance manual — VUW 246/5-3 R6 (GC 47-044-88), VUW 286/5-3 R6 (GC 47-044-89), VUW 286/5-3 R6 LPG (GC 47-044-90), ecoTEC PRO 24 VUW 246/5-3 R6 (2017) (GC 47-044-88), ecoTEC PRO 28 VUW 286/5-3 R6 (2017) (GC 47-044-89), ecoTEC PRO 28 VUW 286/5-3 R6 LPG (2017) (GC 47-044-90)
manualmanualVAILLANT appliance manual — VUW 246/7-2 (GC 47-044-79), VUW 286/7-2 (GC 47-044-80), VUW 346/7-2 (GC 47-044-81), ecoTEC SUSTAIN 24 VUW 246/7-2 (2017) (GC 47-044-79), ecoTEC SUSTAIN 28 VUW 286/7-2 (2017) (GC 47-044-80), ecoTEC SUSTAIN 34 VUW 346/7-2 (2017) (GC 47-044-81)
manualmanualVAILLANT appliance manual — ecoTEC 610 VU 10 CS/1-5 (2023) (GC 41-694-45), ecoTEC 615 VU 15 CS/1-5 (2023) (GC 41-694-46), ecoTEC 620 VU 20 CS/1-5 (2023) (GC 41-694-47), ecoTEC 625 VU 25 CS/1-5 (2023) (GC 41-694-48), ecoTEC 630 VU 30 CS/1-5 (2023) (GC 41-694-49), ecoTEC 635 VU 35 CS/1-5 (2023) (GC 41-694-50), ecoTEC PLUS 826 VUW 20/26 CS/1-5 (2023) (GC 47-044-92), ecoTEC PLUS 832 VUW 25/32 CS/1-5 (2023) (GC 47-044-93), ecoTEC PLUS 836 VUW 30/36 CS/1-5 (2023) (GC 47-044-94), ecoTEC PLUS 840 VUW 30/40 CS/1-5 (2023) (GC 47-044-95)
manualmanualVAILLANT appliance manual — ecoTEC PLUS 940 VUI 30/40 CS/1-5 (2023) (GC 47-044-96)
manualNo technical questions yet for this part.
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