Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 65·4.33
Bases for back boilers
Back boilers must be adequately protected from heat by standing on either a hearth designed for solid fuel appliances or, unless the manufacturer states otherwise, a base complying with Diagram 4.5.
A back boiler should be adequately protected to shield the fabric of the building from heat by standing it on –
(a) a hearth intended for a solid fuel appliance. See Diagram 3.7(a); or
(b) unless otherwise stated in the manufacturer's instructions, a base complying with Diagram 4.5.
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