How do I troubleshoot a low millivolt reading

Can I use this to replace a hot surface ignitor (HSI)

As a backflow preventer repair kit designed for streamlined maintenance

Rigid Construction: Built for continuous duty in residential electric furnaces

Amana-Goodman 11142201 Collector 326058-756 How do I troubleshoot aThe Amana Goodman 11142201 Collector Box Gasket is a critical OEM replacement component engineered for high efficiency gas furnaces. This precision engineered furnace inducer gasket provides an airtight seal between the collector box and the inducer blower assembly, preventing the leakage of combustion gases and condensate. Manufactured to exact Amana Goodman replacement part specifications, it ensures the integrity of the secondary heat exchanger