Have you ever tried to hire a pool professional to change the pool light bulb in your pool? Have you been having trouble finding someone? You’re not alone.
There aren’t many pool service companies that will replace pool light bulbs. Do you know why? I do and I’ll explain in detail:
Many years ago when I was a young pool boy I used to replace pool bulbs for everyone and I soon found out that no matter how careful I was, no matter how much time I took, no matter what tricks of the trade I used, light fixtures would still randomly leak. I figured about 1 in 5 pool bulbs that I replaced would allow water to leak into the fixture within a year. 
And, when water gets inside the pool fixture housing, the whole fixture should be replaced for safety. The conversation usually went like this: “Gosh Mike, I’m really sorry that the light leaked but I know you warranty your work and I know the fixture should be replaced for safety so I guess we’ll need a new fixture…” And being the stand-up company that we are, we would replace the entire pool light fixture at no additional cost to the customer and lose money while doing so.
A pool light bulb retails for about $30-40. A new pool light gasket for the fixture is about $25. Labor for the repair would be $100-150. Profit on a successful job would be about $120. The cost of a new fixture is about $200 (wholesale). So for every five bulb replacements I would make $600 and then have to eat $200 plus my call-back labor on the light fixture that leaked. So, that’s six times I’ve visited a pool and I’ve netted $400 in addition/ minus the extra warranty labor. All told that’s about $50 profit per job which just isn’t enough income to make light bulb replacement worth while :(.
Pool light bulb replacement technicians are difficult to find because even the best techs can’t guarantee that the light wont leak. With every one out of five fixtures leaking, the call-back percentage is just too high so pool tech’s refuse to replace a pool light bulb. What the pool guy will replace is the entire fixture. After mark-up and labor a traditional halogen white light fixture is about $500 (LED lights are MUCH more expensive). There’s a big difference between $500 and $150! Its not fair to the customer to have to pay $500 for a burnt out bulb yet its bad business to constantly be warrantying lights with new fixtures.
Its a tough situation but because pool light fixtures leak so often pool service companies wont perform pool light bulb replacement.
Sincerely,
Mike the Poolman
P.S.
And for the record: we will only replace bulbs for customer’s we have on our weekly pool service route. And, we specifically inform them that we cannot warranty the light if it leaks (many customers opt for replacing the entire fixture and getting the warranty). Otherwise, we will NOT replace a pool light bulb.
Very well said.