Upon are customer stated that heating system was not working properly and turning on and off. After input of 27 year old system found that system is over heating due to inducer draft motor and single wall flue pipe. Blower wheel is very dirty. Gave customer estimate on repairs for system do not recommend due to age and condition of system. There can still be more issues even with repairs being made and there is no warranty on repairs. Do recommend speaking with our install supervisor about updating system, customer is interested in getting a quote for a full system replacement and also needs adjustments for system due to bathroom being built in the area. Customer approved to speak with install supervisor before making any repairs to system.