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Bigg Dogg
25-01-2012, 04:46 PM
I have a Lennox CR33-24F cased down flow evaporator coil, this is a v configuration with the
condensation tray where the two coil meet in the center.
Can I use this evaporator in a up flow configuration?
I really can't think of why it would not work, other than matching the unit to the furnace.
Thank Rod

chemi-cool
25-01-2012, 06:00 PM
Up flow will turn it into flooded evaporator.
I requires different design.

Magoo
25-01-2012, 07:30 PM
You will change the refrigerant flow to air flow from counter flow to parallel flow, loose coil efficiency and have TX valve problems, you will need to interchange the coils.

Bigg Dogg
30-01-2012, 04:47 PM
This list full of morons.

The Viking
30-01-2012, 05:13 PM
This list full of morons.

Thank you Mr Dogg,
I for one fully agree with you.
A simple way of picking them out is their post count, anything less than about 500 and you have to take their post with a pinch of salt, if it's less than 50 well...


Now for your original question and why people haven't exactly queued up to give you the answer you want.
1. See previous paragraph.
2. The evaporator in your Lennox unit has been designed for liquid refrigerant to be injected in to the bottom row of each coil, as the refrigerant absorbs heat it will evaporate in to gas. This means that as it travel upwards in the coil the refrigerant becomes lighter and lighter.
Now, if you turn this coil upside down the liquid will be introduced at the top of the coil and your mixture travel downwards within the coil.
This is a potential compressor killer which is why the manufacturers avoid it at all costs.


Now, having been involved in several IT room and IT hall refurbishments and faced what I assume is the same challenges as yourself...
The best solution is normally to leave the A/C units as they are but to install external ducting to change the airflows.

Whichever way you decide to go, I wish you the best of luck.

:cool:

.

frank
30-01-2012, 07:50 PM
Good reply Viking.......I can't see that we need to add anything else

:)

Rep points added

monkey spanners
30-01-2012, 08:12 PM
Hey Bigg Dogg!

Generally with evap coils the air and refrigerant go in opposite directions, so if the air goes front to back through the coil, the coil is piped for the ***** to go from back to front, that way the coldest gas meets the coldest air and the warmest gas the warmest air, this helps with superheating the refrigerant (don't worry about superheat its way complex), with the air being hotter with this flow arrangement you need less evap coil for superheatin' so more can be used to make the room nice and cool.

If you change the airflow from down flow to up flow there is a possibility that it won't work as well as it used to due to both the air and refrigerant going across the coil in the same direction and more coil being needed for superheating.

Your best bet would be to talk to Lennox and see what the coil is designed and rated for.

You do your countrymen a dissevice by being rude and disrespectful on an international forum.

Magoo
31-01-2012, 01:22 AM
Hi Chemi,
you and I are morons.

mad fridgie
31-01-2012, 04:08 AM
Hey magoo, "NO" self promotion please!!!!!!!!!!!!!!!!

chemi-cool
31-01-2012, 10:25 AM
Hi Chemi,
you and I are morons.


Looks insulting, we will have to think of some reaction.


Moron (psychology), disused term for a person with a mental age between 8 and 12, and a common insult for a person considered stupid (or just a generic insult)

Bigg Dogg
31-01-2012, 03:23 PM
Wow, incredible what people come up with.
Not turning the unit up side down.
No txv, metered.
The coil is in the same position as the down flow configuration, just the air flows the opposite direction.
This coil setup is no different that the V end of a N-coil.
Can anybody come up with a logical reason why this will not function.

install monkey
31-01-2012, 05:28 PM
turn the unit upside down,or consult lennox

Wow, incredible what people come up with.
Not turning the unit up side down.
No txv, metered.
The coil is in the same position as the down flow configuration, just the air flows the opposite direction.
This coil setup is no different that the V end of a N-coil.
Can anybody come up with a logical reason why this will not function.

monkey spanners
31-01-2012, 05:45 PM
Wow, incredible what people come up with.
Not turning the unit up side down.
No txv, metered.
The coil is in the same position as the down flow configuration, just the air flows the opposite direction.
This coil setup is no different that the V end of a N-coil.
Can anybody come up with a logical reason why this will not function.

It'll work fine! Just charge to superheat as its got a piston. HTH

culon61
17-05-2012, 03:45 PM
In the upflow position, the coil is on top of the furnace.
In the downflow position, the coil is position on the bottom of the furnace.
The evap coil must be placed after the flow of air through the furnace.
Air must passes the furnace before it go to the coil.

aramis
17-05-2012, 05:49 PM
Thank you Mr Dogg,
I for one fully agree with you.
A simple way of picking them out is their post count, anything less than about 500 and you have to take their post with a pinch of salt, if it's less than 50 well...


Tks for giving us hope! :D