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Grant VortexBlue Internal 21 review

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Grant claims its VortexBlue range of oil-fired, heat-only boilers burns with a blue flame that’s ‘greener’ than ever before, so it should help to heat your home very efficiently. The Internal 21 model is the smallest in the range, but would owners of this regular boiler recommend it? Read our full review to find out more.
Is it worth your money?
Or is it a waste of cash?
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