Then you are not going to be able to repair that. Call a repair specialist and get it serviced before Winter. Open flued WAU's are not for diy repairs.
Sorry to butt in KP
Badly or un-maintained warm air heaters are extremely dangerous and have the abillity to spread Carbon Monoxide to all corners of your home
a flame visible in a place where a flame has not been seen before should start warning bells ringing LOUDLY!!! Turn the unit off and contact a Gas specialist holding CCN1 + HTR1 Certification!!
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