Possible causes, not a remote diagnosis
Nesting material, deposits, fallen masonry or a damaged termination may obstruct a passage. The obstruction and the damage that produced it can require separate work.
What to document safely
Keep photographs of debris that has already fallen into an accessible area. Record the appliance and the last known normal use without poking rods or tools into the passage.
Keep the appliance model, fuel, previous report and date of last service together. A clear sequence of events can be more useful than deciding in advance which component must be replaced.
Your next service conversation
Arrange a chimney inspection and describe the concern when booking. Ask how the full passage will be checked after clearing and whether an appliance specialist or wildlife professional is needed.
Animal activity and chimney blockage assessment →Is clearing the obstruction enough to restart?
Not necessarily. Ask the professional to assess why it occurred, whether damage remains and what must be completed before reuse.
Ask for evidence before approving repairs
Request a report that distinguishes what was observed from what remains uncertain. Ask the company to identify any area it could not inspect and whether another trade is needed. If a major repair is proposed, compare a second written scope using the same appliance details and findings.
Do not treat a directory profile, an estimate or this page as clearance to use an appliance. Ask the attending professional what must be resolved before reuse.
Read the detailed guide and its sourcesTake the service question to your location
Use the local guide to prepare questions about access, building history and the authority responsible for your address. The service brief is national guidance; local permits and current burn restrictions must be checked separately.