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2020-08-20, 22:17   #34
ewmayer
2ω=0

Sep 2002
República de California

5·2,351 Posts

Quote:
 Originally Posted by Prime95 At the rumored price, the Radeon VII Pro may be more appealing.
Reminds me, been a while since I did any price-checking on legacy R7s (probably because I am definitively done w/my build-out using same, even if by magic I could score some cheap ones, the electricity bills and you'd-need-to-run-the-AC-even-on-cool-days aspect would make it a no-go) ... usual XFX-R7 link on Amazon shows cheapest used @$1349, but I see a new one one eBay for$999, which is not horrible. And even if no "make offer" option, one can PM the seller to do that ... worst they can do is turn you down.

2020-08-21, 03:11   #35
retina
Undefined

"The unspeakable one"
Jun 2006
My evil lair

5·7·191 Posts

Quote:
 Originally Posted by ewmayer ... the electricity bills and you'd-need-to-run-the-AC-even-on-cool-days aspect would make it a no-go ...
Why not duct the hot exhaust to outside?

2020-08-21, 03:20   #36
Xyzzy

Aug 2002

43·199 Posts

Quote:
 Originally Posted by retina Why not duct the hot exhaust to outside?
Or use it to heat your hot water?

 2020-08-21, 05:11 #37 Uncwilly 6809 > 6502     """"""""""""""""""" Aug 2003 101×103 Posts 5·2,179 Posts Or run a chiller unit in the summer.
2020-08-21, 06:50   #38
pinhodecarlos

"Carlos Pinho"
Oct 2011
Milton Keynes, UK

2×33×5×19 Posts

Quote:
 Originally Posted by Xyzzy Or use it to heat your hot water?
Problem is the amount of heat: air vs water (specific heat capacity, flow, and temperatures), plus any mechanical efforts.
What’s the heat source, air? What’s mass flow and temps of the rejected heat?

Last fiddled with by pinhodecarlos on 2020-08-21 at 06:53

2020-08-21, 19:34   #39
ewmayer
2ω=0

Sep 2002
República de California

5×2,351 Posts

Quote:
 Originally Posted by retina Why not duct the hot exhaust to outside?
Believe me, the thought had occurred to me, but I don't own the space, and the required hackery into, say, the exhaust ducting for the clothes dryer would violate my lease. But in order to give the AC a hand on-the-cheap, couple days ago ordered one of these. Where I live is generally a dry climate, evaporative cooling is definitely a good option.

2020-08-22, 23:53   #40
chalsall
If I May

"Chris Halsall"
Sep 2002

11,087 Posts

Quote:
 Originally Posted by ewmayer Where I live is generally a dry climate, evaporative cooling is definitely a good option.
You are, of course, aware this doesn't change the enthalpy in a closed system?

Your machines won't notice any difference; humans might actually find it (subjectively) slightly warmer because they can't sweat as quickly.

AC Engineers spend a lot of time learning about the difference between dry bulb and web bulb sensors...

2020-08-22, 23:56   #41
retina
Undefined

"The unspeakable one"
Jun 2006
My evil lair

5·7·191 Posts

Quote:
 Originally Posted by chalsall ... humans might actually find it (subjectively) slightly warmer because they can't sweat as quickly.
I think you mean: humans might actually find it (subjectively) slightly cooler because the sweat evaporates more quickly.

Lower humidity == more comfortable for a human when it is hot.

2020-08-23, 00:04   #42
chalsall
If I May

"Chris Halsall"
Sep 2002

11,087 Posts

Quote:
 Originally Posted by retina I think you mean: humans might actually find it (subjectively) slightly cooler because the sweat evaporates more quickly.
Incorrect.

The kit ewmayer has ordered from Amazon is basically a bowl of water with a fan. Thus, the kit introduces moisture into the air, reducing the humans' opportunity to add to the vapor pressure of the closed system.

2020-08-23, 00:06   #43
retina
Undefined

"The unspeakable one"
Jun 2006
My evil lair

5·7·191 Posts

Quote:
 Originally Posted by chalsall The kit ewmayer has ordered from Amazon is basically a bowl of water with a fan. Thus, the kit introduces moisture into the air, reducing the humans' opportunity to add to the vapor pressure of the closed system.
Okay, makes sense. Thanks.

2020-08-23, 00:22   #44
chalsall
If I May

"Chris Halsall"
Sep 2002

11,087 Posts

Quote:
 Originally Posted by retina Okay, makes sense. Thanks.
Please forgive me for this, but I'm "in that mode".

This is similar to the question "Can I cool a room by running a fridge with the door open?

Cold can't be created. Heat can be moved.

Unless there is a route to exhaust heat, a closed system will always get warmer.

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