An external wall-mounted oil-fired system boiler that frees up indoor space entirely. The Grant Vortex Eco External Wall Hung System 16-21kW Boiler Only (VTXSOMWH16/21) sits outside on a wall bracket, connects directly to a sealed heating system, and delivers up to 21kW with ErP A-rated efficiency — ideal for UK homes off the gas grid where indoor plant space is tight.
Key features:
- External wall-hung installation — no boiler taking up utility or kitchen space, and no separate boiler house needed
- System boiler with integral components for connection to a sealed heating system
- Supplied as the boiler only — flue kit and accessories purchased separately
- 18.7kW set output, 21kW maximum — suited to small and medium homes
- ErP A-rated for heating efficiency, helping keep oil consumption down
- HVO-ready: compatible with hydrotreated vegetable oil for a lower-carbon fuel path
- Eligible for a 5-year guarantee when installed by a Grant G1 Installer
Use cases / applications:
- Off-gas-grid homes replacing an ageing internal or external oil boiler
- Properties where internal space is needed back — the boiler moves outside
- Sealed-system installations with an unvented cylinder (no separate feed and expansion tank)
- Future-proofing against fuel transition with HVO compatibility
Why choose this product: Grant is the UK's leading name in oil-fired heating, and the Vortex Eco External Wall Hung System combines that pedigree with a compact 832mm x 684mm footprint, A-rated efficiency and a wall-mounted design that puts the boiler out of sight and out of the way.
Key Features
-
Type: External wall-hung oil system boiler
-
Supplied as: Boiler only (flue kit sold separately)
-
Brand/Range: Grant — Vortex Eco
-
Model/Code: VTXSOMWH16/21
-
Output: 18.7kW set output, 21kW maximum (71,654 BTU)
-
Efficiency: ErP A-rated for heating
-
Fuel: Oil, HVO-ready
-
Installation: External wall-mounted; connects to a sealed system — professional installation by an OFTEC-registered engineer required
-
Warranty: 5 years when installed by a Grant G1 Installer (subject to manufacturer's T&Cs)
Specifications
| Specification |
Details |
| Brand |
Grant |
| Product |
Vortex Eco External Wall Hung System 16-21kW Boiler Only |
| Manufacturer Stock Code |
VTXSOMWH16/21 |
| EAN |
5060090372703 |
| Range |
Vortex Eco |
| Category |
Oil Boilers |
| Sub-Category |
Domestic Boiler |
| Type |
System boiler, external wall hung |
| Supplied As |
Boiler only |
| Fuel |
Oil (HVO-ready) |
| Set Output |
18.7kW |
| Maximum Output |
21kW |
| ErP Heating Rating |
A |
| Height |
832mm |
| Width |
684mm |
| Depth |
351mm |
| Weight |
96.1kg |
| Colour |
White |
| Ready for 20% Hydrogen |
No |
| Ready for HVO |
Yes |
| Magnetic Filter Included |
No |
| Warranty |
5 years (subject to manufacturer's T&Cs, G1 Installer) |
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