I spoke to the homeowner about his concerns. He was wanting to change the UV bulb out in his air purifier located in the supply plenum. He said the company that installed it, had it installed in a portion of the plenum that the bulb was not able to be removed without removing the base of the air purifier. I removed the air purifier base, the homeowner widened the UV bulb slot to allow the bulb to be removed when it is sealed into the plenum. I sealed the base back onto the plenum using air sealant to ensure no air leaks are present. Reset power to system and checked operation of the light. Everything is working at this time.