Ideal Rear Flue Seal Logic Heat 177864

The Ideal rear flue seal, part 177864, is a gasket-type seal fitted at the rear flue connection on Ideal Logic Heat appliances. It closes the joint between the flue outlet and the boiler casing so that combustion products stay within the flue path rather than escaping at the connection. The seal is listed under gaskets, seals and washers and is used across a number of Logic Heat and Ideal Commercial variants.

• Cracking, hardening or flattening of the seal at the rear flue outlet
• Soot marks, staining or condensate traces around the flue connection
• Combustion readings outside the expected range during a service or flue gas analysis
• Smell of combustion products or noticeable draught at the rear flue joint
• Seal disturbed or damaged while the flue was removed or the appliance was serviced

• Check the appliance model and GC number against the compatibility list, as the seal covers several Logic Heat variants
• Cross-reference the alternative number 8901860 when working from older documentation
• Inspect the flue joint and any adjacent gaskets while the appliance is open, and replace other seals that show wear
• Confirm the flue arrangement and rear outlet type on the appliance before fitting
• This part is fitted to a gas appliance; installation must be carried out by a Gas Safe registered engineer.