120V bulb in 12 V lamp socket

pgershon

Gold Supporter
Jul 15, 2012
307
East Hampton NY
Pool Size
30
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Hayward Aqua Rite (T-15)
One of my spa lights dies and I decided to replace both bulbs with color LEDs. When I took the two lights out of the water I discovered one was a 120V T-4 bulb and the other a 12V R-20 (both Pentair spa lights). I ordered replacement bulbss based on the labels, but was concerned that it made no sense to put a 120V and a 12V on the same circuit in symmetrical alignment. I looked for a transformer for the 12V lamp and couldn't find it. Then I opened the fixture and found a 100 W 125V bulb in it. My builder had put a 120V bulb in the 12V figured (with no transformer).

So my question - how do I replace bulb? Do I put in another 120V bulb or do I add a transformer as install a 12V bulb? If I do the former, can I use the same 120V bulb as for the other fixture?
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
29,053
Northern NJ
Pool Size
35000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
I am confused.

Are you discussing one light with 2 bulbs or two lights with one bulb each?

Is there 120V or 12V going to the light?

What type of socket base do the light(s) have?

Post pics of the lights and bulbs.
 

pgershon

Gold Supporter
Jul 15, 2012
307
East Hampton NY
Pool Size
30
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Hayward Aqua Rite (T-15)
Thanks for responding.

Two lights, one bulb each. Both lights ultimately wired to a common breaker and relay. I only see evidence of 120v. One light fixture says 120V T-4 bulb and has a T-4 bulb in it (clearly 120V). The other is labeled 12V R-20 bulb, but has a 120V 100W bulb in it. I do not see a transformer anywhere so its pretty clear to me its been running as 120V despite the 12V label on the fixture. I'd liek to confirm that it is safe to continue using 120V bulbs in the fixture despite its label. Photos attached of bulb and both fixtures (not posting the T-4 bulb shattered into many pieces).
 

Attachments

  • IMG_3669.jpeg
    IMG_3669.jpeg
    354.1 KB · Views: 9
  • IMG_3666.jpeg
    IMG_3666.jpeg
    332.4 KB · Views: 9
  • IMG_3634 2.jpeg
    IMG_3634 2.jpeg
    335.6 KB · Views: 9

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
29,053
Northern NJ
Pool Size
35000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
It looks to me like the same fixture is used for both 120V and 12V bulbs.

20170517_112110-jpg.61339


A 100W 12 volt R-20 bulb is an incandescent bulb...


I think you are fine to use 120V bulbs in both lights as you found it.
 
Last edited:
Thread Status
Hello , This is an inactive thread. Any new postings here are unlikely to be seen or responded to by other members. You will get much more visibility by Starting A New Thread