No heat in Lawrenceville, arrived on site, found system running. Found static pressure across filter abnormally high, replaced with filter to slow better air flow. Found system without water safty at all. Recommended installing due to code as well as water damage prevention. Found improperly ran gas line with no drip-t, needs to be addressed per code as well as to prevent gas valve from clogging. Recommended installing air purifier to improve indoor air quality as well as electrostatic media to improve air flow. Also found warn ignitor that may be failing causing unit to go into lockout because it would be in able to light hot gasses. Replaced ignitor and filter for customer. Unit is operating normally at this time.