Glow-worm Energy
The Glow-worm Energy is the brand's core range, available as combi, system and regular.
At a glance
- Configurations: Combi, System, Regular
- Best suited to: Budget-conscious replacements across most home sizes
- Fuel: Mains natural gas (some variants are LPG-convertible, check the manufacturer’s data).
Specifications
Match the badge in front of you to a row before you use any of this. Every figure below was read from the Glow-worm literature listed under Sources at the foot of this page, checked 6 September 2026. Outputs, variants and part numbers change by year, so the appliance data plate is still the last word.
| Variant | GC number |
|---|---|
| Energy7 25c combi | 47-019-60 |
| Energy7 30c combi | 47-019-61 |
| Energy7 35c combi | 47-019-62 |
| Energy7 12s system | 41-019-53 |
| Energy7 15s system | 41-019-54 |
| Energy7 18s system | 41-019-55 |
| Energy7 25s system | 41-019-56 |
| Energy7 30s system | 41-019-57 |
| Energy7 12r regular | 41-019-58 |
| Energy7 15r regular | 41-019-59 |
| Energy7 18r regular | 41-019-60 |
| Energy7 25r regular | 41-019-61 |
| Energy7 30r regular | 41-019-62 |
- The plate shows the full designation, for example Energy7 25c -A (H-GB). Glow-worm prints the article number and the GC number together in the validity section at the front of each current manual.
- The serial carries the build date: the third and fourth digits are the year of production and the fifth and sixth the week. Registration has to happen within 30 days of installation.
Where the data plate is
Data plate on the underside of the appliance, fitted at the factory, carrying the serial number barcode and the GC number together. The serial is repeated on the magnetic short-instructions card supplied with the boiler.
Reading the plate
Worth knowing on site
- One of Glow-worm's most widely fitted ranges.
- Combi, system and regular options, confirm from the data plate.
On the tools
As one of Glow-worm's most widely fitted ranges, Energy is a common sight on budget-conscious domestic work across most home sizes. Being part of the Vaillant Group, parts and technical support generally follow a similar pattern to Vaillant's own budget ecoFit pure range.
Variants and configuration
Energy covers combi, system and regular formats, giving it a broad footprint similar to Ideal's Logic or Baxi's Assure rather than a narrow single-configuration range. Confirm which format and output is fitted from the data plate, since Energy's spread means the badge alone tells you little.
Where it sits in the range
Energy sits as Glow-worm's core domestic range, positioned above the entry-level Betacom4 on features and configuration options. As part of the Vaillant Group, it shares some of the value positioning that ecoFit pure holds in Vaillant's own line-up.
Finding the manual and the data plate
For the exact outputs, gas rate, dimensions and commissioning figures, work from the appliance’s data plate and the manufacturer’s installation and servicing instructions. The GC (Gas Council) number and serial are on the data plate, usually behind the front panel or on the underside. Glow-wormpublishes its manuals and support at Glow-worm support.
Frequently asked
Useful while you’re on the tools
More from Glow-worm
Manifold is not affiliated with or endorsed by Glow-worm. Brand and model names are used only to help engineers find the right resources. Specifications and available variants change by year and model, so always work from the appliance’s data plate and the manufacturer’s own installation and servicing manual. Gas work must be carried out by an appropriately Gas Safe registered engineer.