HPS Temperature

SO I switched over to my 400W HPS from my MH now that I have switched 12/12 and I have always been under the impression MH run hotter than a HPS. So why would it go from 77-79 to 84-86? Please I really could use some input on this.

To make it simple different spectrums use energy different and produce light and exchange heat diff whiter brighter more heat orange less light less heat...in a nutshell

Like I said I was under the impression MH run hotter so why is my HPS running hotter? MH are less efficient with the conversion of electricity into light and the left over is observed as heat. So could it just be that I have a cheap china made HPS bulb that is horribly less efficient than my china made MH bulb??

my hps runs hotter than mh

A new bulb may cause more heat than old, mh in my experiance is like 20 percent hotter. Hows u grorite?

ACTUALLY, according to my IR thermometer the temperature of the glass cool tube with the MH 213F and the HPS is 170F. What makes the HPS "hotter" is that it emits more light energy. Meaning the hps is more efficient at converting power(watts) into usable energy(light). MH is less efficient thereby putting off more waste(heat). Nevertheless, the increased light energy will equate to more heat. It's complicated but simply put yea HPS will make your grow area warmer despite running cooler.

Think of it like a cloudy day that is 75 degrees feels cooler than a sunny day at 75 degrees.

YES raidiant heat!! bravo..

my hps runs hotter than my mh

Nice shim, I bought an IR thermometer recently and love it.
I discovered some micro climates in my grow tent that have since been fixed.

FWIW my HPS runs cooler than my HPS, both are new 600w bulbs. When I swithed to HPS a while back I had to turn my fan down to a crawl to keep temps up (pulls through a cool tube and exhausts outside room). It dropped about 7 degrees f in a 5X5X8 room in a basement where I need the bulbs for heat.

Not sure why I would be different but it is for sure generally cooler since the switch to hps

chuggyt said:

my hps runs hotter than my mh

Click to expand...

Have you used any sort of instruments to prove this or is it the hand test? The only reason a HPS would burn hotter than an MH if it has considerable mileage on it or it's a cheapo lamp.

I was kinda lost following until Mrshim broke it down barney style with that analogy of the ''cloudy day, sunny day.'' Cool.