Writing to inquire if there is a generic preventive maintenance/inspection checklist for residential type gas forced air heaters which apartment maintenance staff (of various degrees of expertise and certification), could use to inspect and perform service on gas heaters. Short of calling in a 'professional', the intent is to do reasonable users service and maintenance on gas heaters on a regular basis to prolong the life and to catch any signs of excessive wear or a potential fire hazard. Thanks for any insights.

Following up on the question on gas or electric heater's date of manufacture/ age by looking on a data plate- e.g. a standard convention for showing the date/year of manufacture which is used by all or many manufacturers.. Thanks for your insights.

Best to send the staff to a real school or classes but a look on Google might find some HVAC books.

Most manufactures use various ways to tell the date of manufacturer. Usually it is incorporated into the serial number and they all have a different way to state the serial number so there is no universal way to tell age.

You can order these and they are a good source of info for age and other items.

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