Worcester Greenstar Heatslave II: the oil combi option
The Heatslave II brings combi-style, on-demand hot water to homes without mains gas, which most oil boilers can't offer directly. It's a genuinely different proposition from Worcester's standard heat-only oil boilers.
Where the Heatslave II oil combi usually comes from
Because oil combis heat water on demand from stored oil rather than mains gas, output and flow rate are engineered differently from a gas combi of the same nominal size. The Heatslave II works well for smaller rural households wanting to lose the airing cupboard cylinder, but larger households with high simultaneous demand are often still better served by a heat-only oil boiler and cylinder.
Who should undertake the work
- Gas appliance work must be completed by a suitably qualified Gas Safe engineer
- Oil appliance work should be completed by a suitably qualified OFTEC technician
- Jamie Crawford Heating states both Gas Safe and OFTEC registration
Detail that affects your quote for the Heatslave II oil combi
- Mains-pressure hot water without keeping a cylinder
- Suits smaller or moderate-demand rural households
- Requires the same tank, line and OFTEC-compliant installation as any oil system
- Servicing intervals follow standard OFTEC oil-boiler practice
- Larger households may still be better served by an oil regular boiler
Questions we get asked
- Does an oil combi need a separate feed and vent tank?
- No, being sealed and pressurised it doesn't rely on a header tank the way older gravity oil systems did.
- Is oil combi output comparable to a gas combi?
- Broadly, for a household of similar size, but the tank, line and OFTEC servicing needs are specific to oil and should be sized by survey rather than assumption.
Local context for the Heatslave II oil combi
Villages off the gas network around the Mendips are exactly where this model gets asked about most, usually by households replacing an old cylinder-fed system and wanting to free up airing-cupboard space.
Related help pages
- Heatline rangeHeatline combi boilers: a budget option for tight installs
- Installation decisionWorcester oil boilers: internal versus external siting
- Viessmann rangeViessmann Vitodens: a premium stainless-steel combi
- Boulter rangeBoulter oil boilers: servicing a legacy brand still in use
- Property typeChimney-flued appliances: what makes a chimney suitable
- Portfolio schedulingScheduling servicing efficiently across a rental portfolio
Where we deal with this
Book a visit for the Heatslave II oil combi
In practice: A genuinely useful format for the right rural household, but size it against real hot water demand rather than the appeal of losing the cylinder.
Include the appliance make and model in your enquiry so the correct technical information can be checked.
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