Monday, May 8, 2017

An Easiest Overhaul Of Dead T12 Fluorescents In A Kitchen

This post converts content of a Google Photos Album , to blog format.

These T12 fluorescent lights buzz loudly, and two of six 30 watt tubes are dim. I will find that two of the three heavy ballast units are oozing nasty PCBs. Power consumption is not just the tube draw. From the blog of Hovey Companies in Michigan , now Windemuller , find that total fixture draw of each eight-foot unit is 178 watts. Draw with dying ballasts is perhaps more. I might fix the buzzing with new ballast units, $38 each at Home Depot, and preemptively relamp at $5 per tube, perhaps giving another fifteen years of fixture service interrupted only by annual take-down of dead flies and stink bugs littering the plastic lens panes.

The home owner knows I have a better solution that costs no more. I have similarly replaced T12 fluorescent fixtures in two bathrooms.

It has taken two hours to demolish the found fluorescent fixtures and to install six Lithonia 7" LED Versi Lites , each 10.2 watts, 640 lumens, 3000°K color temperature. The LED disk downlights are attached to drywall with 1 1/4" drywall screws and are directly powered by 120 VAC (AC light engines) via 18 gage conductors. I failed at this installation, to seal ten half-inch holes in the drywall, but returned a week later with a better notion of the importance of that sealing. These holes for toggle bolt screws are little obstructed by steel bodies of fluorescent fixtures, and were the path a big stink bug could crawl through, for forty lens-littered years. A stink bug could not crawl past a lens or through small gaps above fixture aluminum frames.

The revived and silent lighting is much brighter. Total power draw is now 61 watts maximum, and will likely be dimmed much of the time, to less than fifty watts. This peak power consumption is down from 534 watts (or more with failing ballasts), a more than 90% reduction. Assume this condition is maintained fifteen years maintenance-free, before an anticipated grand kitchen overhaul where lights still have $30 value each, then used elsewhere. Assume an alternative miserly life with lights on just three hours per day if still non-dimmable fluorescent. Assume cheerful eight hours per day usage as LED with dimming to average 60% power, 300 watt-hours per day, 365 days per year. Saved electricity is 365*(3*534 - 300)/1000  = 475 KWH, a first-year savings of $52. A perpetual energy savings of $52 per year has fifteen year present value of $1352 if energy cost grows at 10% per year vs 3.2% general inflation and 5% annual interest cost of money if borrowed. I charged $240 for the job, better-compensated in friendship cemented with gift value of more than $1000, and expected enjoyment of a brighter buzz-free quality of life.

If I had only overhauled the found fluorescents at cost of $120 for new ballasts and $30 for new tubes, for the same $240 job cost, I would have robbed this friend of $1000 and diminished her quality of life. Fortunately, I know to do better. Now, do you?

Do know, I would be an even better friend in a kitchen overhaul now, where I would better light up the kitchen with visible LED disk downlights more pretty than Versi Lites and bug free forever. The current-best offering in this would be Lighting Science 6" Glimpse. The better light might be like this at another home in this wonderful Lake Oswego, Oregon condominium complex, soon to be my home: