Reptile & Amphibian Forums

I'm using the 20 watt halogen puck lights in some of my plastic cages, mainly to help me see better when cleaning the cages. However, the low wattage, smooth dimming characteristics and reflective compact housing make them nice daytime heaters.

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Mark

Mark, are you using Reflectix or any other sort of radiant barrier to reflect the heat back into the cage? What is the surface temp of the light?
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Currently keeping:

6.10 Gonyosoma oxycephalum (Javan, mixed colors)

0.0.4 Rhynchophis boulengeri

1.1 Philodryas baroni

1.1 Lampropeltis triangulum multistriata

0.0.1 Rhamphiophis rubropunctatus

0.0.1 Morelia viridis "Aru"

0.0.1 Morelia viridis "Merauke"

1.0 Rhodesian Ridgeback

That is what I like about them, they have a reflector built-in. The heat is directed down for the most part with no mods, especially when kept on a dimmer setting less than full. On full, the UV-filtering glass surface of the housing is very hot. However, dimmed down a bit, it is hot but not damaging to skin at all.

I only use these in small cages where I can leave them dimmed down quite a bit. I think an RHP would be a better choice for most applications, but RHPs are too big for many of my smaller cages. For $12, these pucks are OK.
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Mark

Sorry, I was typing with one hand and holding my kid with the other. In case you're not using a radiant barrier, I'm curious to know how much the reflective housing is preventing heat loss from the light.

If you're not using any sort of radiant barrier outside of the cage, have you ever checked the temperature of outside top of the cage where the light is attached? Could you check for us?

If the cages are stacked I'd like to know how hot the outside top of the uppermost cage is.
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Currently keeping:

6.10 Gonyosoma oxycephalum (Javan, mixed colors)

0.0.4 Rhynchophis boulengeri

1.1 Philodryas baroni

1.1 Lampropeltis triangulum multistriata

0.0.1 Rhamphiophis rubropunctatus

0.0.1 Morelia viridis "Aru"

0.0.1 Morelia viridis "Merauke"

1.0 Rhodesian Ridgeback

>>Sorry, I was typing with one hand and holding my kid with the other. In case you're not using a radiant barrier, I'm curious to know how much the reflective housing is preventing heat loss from the light.
>>
>>If you're not using any sort of radiant barrier outside of the cage, have you ever checked the temperature of outside top of the cage where the light is attached? Could you check for us?
>>
>>If the cages are stacked I'd like to know how hot the outside top of the uppermost cage is.
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>>Currently keeping:
>>
>>6.10 Gonyosoma oxycephalum (Javan, mixed colors)
>>
>>0.0.4 Rhynchophis boulengeri
>>
>>1.1 Philodryas baroni
>>
>>1.1 Lampropeltis triangulum multistriata
>>
>>0.0.1 Rhamphiophis rubropunctatus
>>
>>0.0.1 Morelia viridis "Aru"
>>
>>0.0.1 Morelia viridis "Merauke"
>>
>>1.0 Rhodesian Ridgeback
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Mark

I left one puck on full (20 watts) for about two hours in an empty bottom cage with one cage on top of it separated by a 1/4" spacer.

Ambient temp of room: 68 deg

Room is small and very well insulated. Cages tend to stay warm with little wattage when in this room.

Cages: 24w x 18d x 12h

Cage material: High density polystyrene about 3/16 inch thick.

Temperature of the top of the cage above the puck: 124 deg

Temperature of the glass surface of the puck: Over 230 deg, couldn't touch it for more than a fraction of a second. I was using a non-contact thermometer, and I understand those can give inaccurate results when used on a reflective surface. Still, the glass was far too hot to touch.

Next, I turned off the light and let it cool down to a touch-safe temperature, then turned it back on and dimmed it down to a level that was probably closer to 1/2 the wattage. This still produces rather generous heat and a good amount of light. Left that on for 30 minutes.

Cage top above puck: 90 deg
Glass surface of puck: 192 deg

If my cages weren't small, an RHP is the better choice for a heater. I use these pucks mainly for light when I service the cage, then turn them off. In a few cages during the recent cold snap here, I leave some on dimmed down quite a bit, and they keep the air temp in the cages in the high 70s low 80s.
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Mark

Thanks for the post! I've looked at them and almost bought them several times but worried the halogen gas would get too hot. Regarding the light output, would 1 puck provide ample light for a 30x15x15 size cage or would 2 be better? If 2 would provide better light, would you be concerned with the temp getting to high in that small of a cage? Thanks again in advance.

These halogen puck lights put out lots of light and heat when on full. The light is super nice, very pleasing to the eye.

The problem is that when on full, the temperature of the glass surface of the puck is extreme - too hot to touch. The temperature of the cage just above the puck can get over 120 deg when these lights are on full for more than an hour.

What I have found is that they must be dimmed down for the glass surface to be touch safe. Doing that, just one puck in a plastic 24w x18d x12h cage will keep it in the high 70s low 80s in a room that is 68 deg.

Of course alot depends on cage material, ventilation, what type of animals you are housing, ambient air temp of the room, etc. I use them for light when cleaning cages and for supplemental ambient air heat for more tropical snakes during these cool days. Main heat is undercage heat cable.
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Mark

They are attractive. And so much nicer than my method - a paper towel or scrub sponge in one hand and a flashlight in the other.