H2O-cooled heat exchanger: design, setup & use (ex., IceBox)

[Oldmac]

@cracka magik, the cooling loop for the rez only sees the cold water that is used in the house normally. The 30 gal rez is more then adequate buffer for when no cooling water is flowing, but my cooling needs are minimal compared to yours. If you considered a larger rez plus (if needed) adding a additional "drain to waste" house water ckt with soleniod valve on timer, I think you could work it out and not have too much additional domestic water usage.

@spurr, I like the idea of the reflective panels and while I currently don't require them I have helped a few people with there grow room setups. This is something I believe I can use in the future. Thanks.
BTW, what quantum meter are you using? I've borrowed a friends (greenhouse operator) who has a Quantum Field Scout Dual (both sun and electric) that seemed to work pretty good, tho disappointed with LED readings. More a product of how PAR is measured rather then the meter "weighting" I alluded to in another post.

OM

 

[Oldmac]

sorry, double posted.

OM

 

[spurr]

@spurr, I like the idea of the reflective panels and while I currently don't require them I have helped a few people with there grow room setups. This is something I believe I can use in the future. Thanks.

BTW, what quantum meter are you using?

Li-cor LI-190 with a data logger; it's probably the model most used in academia and industry.

I've borrowed a friends (greenhouse operator) who has a Quantum Field Scout Dual (both sun and electric) that seemed to work pretty good, tho disappointed with LED readings.

Sorry to say, but the FieldScout is pretty much a waste, its "quantum response"* is far from ideal, it's really quite poor. A quantum sensor should use near the ideal quantum response. The FieldScouts you used used weight green light much higher than blue and red, that means the FieldScout is not much better than a Lux meter; see the figures below.

Because the FieldScout has such poor quantum response any measurements taken with it should not be considered accurate, sorry to say. Esp. if trying to match the irradiance reported in a study where the researchers used a good quantum sensor, like the Li-cor (e.g., re the study on cannabis and PPFD; the quantum sensor I use is the same they used in that study). The same goes for the Apogee quantum sensors.

It makes sense you would be disappointed with LED readings using a FieldScout, considering the quantum response of the sensor is so poor. It gives low weight to blue and red range wavelengths. If you used a good quantum sensor, ex., like what I use, it would give very accurate reading from LED and LED arrays. That is because all photons within all wavelengths within PAR range (400-700 nm) are given nearly equal weight.

* quantum response is the measurement of the quantum sensor per wavelength with respect to the weighting of photons, or not weighting of photons. An ideal quantum response is when all photons from 400-700 nm are given the same weight.


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Quantum Reponse of all FieldSout models:
http://www.specmeters.com/pdf/3415F Quantum Light Meters.pdf

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Quantum Response of three of the top quantum sensors, I use "C" (the square line is the ideal quantum response):
http://www.licor.com/env/pdf/light/TechNote126.pdf

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Leaf Absorbance Spectra (A) vs Action Spectra of Photosynthesis (B) vs Quantum Yield (C) (all of those have been used to weight photons with respect to light measurement relative to the effect on rate of photosynthesis; but only the last should be used, and even it's flawed):
http://www.licor.com/env/pdf/light/TechNote126.pdf

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Ideal Quantum Response vs Quantum Yield:
http://www.licor.com/env/pdf/light/TechNote126.pdf

​

More a product of how PAR is measured rather then the meter "weighting" I alluded to in another post.

OM

I do not follow you here. Can you elaborate? Ideal measurement of PAR range photons for something like PPFD, means equal weight to all photons, no weighting photons at all.

The work of K.McCree, K.Inada, and many others, on proper weighting of photons for higher plants is not used for the official ideal quantum response (of a quantum sensor). That is because their works are not a rules for all plants, nor plants all all life stages. The work of McCree and Inada, et al., is more of a 'rough guide', their work is accurate enough to tell us generally what is going on. But it's not very accurate, esp. through all life stages for all leafs in the canopy. Not only that, but as I wrote in your thread (which I will get back too, I forgot someone asked me a question there) McCree and Inada used monochromatic lighting for their work, which doesn't account for effects of green photons (driving photosynthesis well) under bright white light.

 

[InjectTruth]

This is a great thread. I am trying to cool a basement room with no windows and have been pouring over all this watercooling, mini split, excel air info for weeks now. Oldmac, your input has been priceless!

Ive been considering burying a water drum about 5-6 ft down, to achieve a constant temp of 50-55F year round. But the logistics of whether or not it would need to be sealed, or could be left open, etc havent been addressed yet.

The idea of running your house intake through a cooling coil ina rez and using that is brilliant. I really need to pursue this idea further.

Thanks again for everyones input in this thread.