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I saw on this post from last year on flow charts and associated DP settings (ft/hd) for Trane Chillers. I am trying to det up some DP devices for measuring flow and I cannot find the Trane Document online, I saw where you had e-mailed it to someone. Is it possible for you to send this to me as well, I would really appreciate it????

the purge unit is a timed style. Yes the chiller has been down for extened amount of time

The evap side looks Ok. You show making 4 degrees thru the bundle with an approach of 2-3 degrees. Check the belly temp and compare it to the evap pressure and leaving chill h2o when you get time. Single pass evaps give some different readings than you might expect.
If you are not doing it, start logging all your readings for your reference!

So you have 73/76 cond h2o in & out with an 84 degree liquid temp off the cond. These machines were usually at 10/10/10 at full load. That is 85/95/105 on the liquid temps. You are showing 8 degrees delta t on leaving water and liquid ref at 60 % load. Its close but I would expect 5-6 degrees. Your thermo's accurate? Also you are only picking up 3 degrees on the water side. Again I would expect 6 at 60%.
Now looking at the Liquid temp vs cond pressure you have 84 degree liquid which shoud show about 2 psi pressure but you report 10 psi which equates to about 102 degrees.
Sooo, my opinion (remember what you are paying for it) is air in the machine causing high head pressure plus some tube fouling in the cond. The only thing saving your butt is the cold tower water which is depressing the high side and keeping you out of surge ( I presume you are not surging). The cond flow looks good.
Those tubes will only take about .0005" of fouling before pperformance starts going downhill and a machine can foul in about a week under the right conditions.
Check out the purge on this unit. What type of purge is it. Was the chiller down for an extended period of time?

Yes I did thank you, Chet

Originally Posted by Control Man

Did you get the EMAIL ?

Did you get the EMAIL ?

Yes, any help would be greatly appreciated. Thank you Chet

Here is the info on Chiller #2 that will not chill water down after switching over from #1 chiller that is running fine. Heres the conditions the Chiller #2 is running at right now:

Load set 60%
Evap pressure: 11" Vacuum
Condenser pressure: 10 PSIG
Oil Pressure: 13PSIG
Condenser Refrigerant Temp: 84 DegF

Condenser Water Temp inlet: 73 DegF
Condenser Water Temp outlet: 76 DegF

Evaporator Water Temp inlet: 58 DegF
Evaporator Water Temp outlet: 54 DegF

Condenser Water Inlet Pressure: 52 PSI
Condenser Water Outlet Pressure: 42 PSI

Note: Both chillers had the Condensers tube brushed at the end of last season by another contractor.

Originally Posted by Chiller Guy

You should be able to pick up fouling by using the approach.

What problem are you having? Perhaps we can help!

Chet

Check your EMAIL , I scanned the flow / pressure drop charts and sent them.

Sounds good, Thanks Chet

Originally Posted by Control Man

Sorry but its not in PDF form , about 30 pages and is a little on the old / abused .

Will see how it scans.

You should be able to pick up fouling by using the approach.

What problem are you having? Perhaps we can help!

Sorry but its not in PDF form , about 30 pages and is a little on the old / abused .

Will see how it scans.

Hi Control Man,

Can you please email the catalog to me, my email address is in my profile.


Thank you, Chet

I have the TRANE CENTRA VAC catalog your refering too.

Is your PCV-4D a single pass or 2 pass evaporator and the catalog has 4 WATER PRESSURE DROP charts in it.


Design info listed is External tube surface Evap 2596 SQ Feet Cond 2491 SQ Feet

2 PASS

Evap 421 - 1540 GPM Cond 525 - 1922 GPM

1 PASS

Evap 1400 - 3080 GPM Cond 1749 - 3844 GPM


1,060 Lbs of refrigerant , 7 Gallons of oil , Operating weight 20,800 Lbs Shipping Weight 20,000 Lbs

What I am trying to determine is if the condenser tubes are fouled or not according to Tranes literature, it states to see the "Trane CenTraVac Catalog for curves showing pressure drop vs. water flow" to determine if the tubes are fouled. This Catalog is what I am looking for.

Thanks, Chet

I figure you should need about 1224 gpm thru the cond for 425 tons @ a 10 delta T. That flows should produce about 13' delta P

The single pass evap can vary if you know the delta T (5-8-10) or the capacity of the pumps it would help.

On those machines we used a SWAG of 2 1/2 gpm per ton on the evap and 3 gpm per ton for the cond for field work

No recommended delta p. It will be a function of flow, but here are the numbers to work with.
Delta p on cond at min flow = 2'
at max flow = 21'

Delta p on 1 pass evap at min flow = 3.5'
at max flow = 15'


P.S. My last post should show the Min/Max flows for a single pass evap, not a double pass.

Chiller Guy

this is good info - also need min max pressure drop recommended through condenser & evaporator

Thanks again, Chet

Originally Posted by Chiller Guy

Chet,
I hope this is some help!

PCV-4D-C1-D2 = Packaged CentraVac
4= 400 Tons
D = part of 100 tons (in this case I beleive it was 25 tons)
C = Evap flow arrangement 1 designating 1 pass
D = Cond flow arrangement 2 designating 2 pass
I think the C & D are correct but can be corrected

My catalog only showes a PCV-4F but this should be close:
Min flow for a 1 pass evap is 1100 gpm
Max flow for a 2 pass evap is 2422 gpm
Cond flow is 411 min & 1505 max
Dinner Calls

Chet,
I hope this is some help!

PCV-4D-C1-D2 = Packaged CentraVac
4= 400 Tons
D = part of 100 tons (in this case I beleive it was 25 tons)
C = Evap flow arrangement 1 designating 1 pass
D = Cond flow arrangement 2 designating 2 pass
I think the C & D are correct but can be corrected

My catalog only showes a PCV-4F but this should be close:
Min flow for a 1 pass evap is 1100 gpm
Max flow for a 2 pass evap is 2422 gpm
Cond flow is 411 min & 1505 max
Dinner Calls

Model: PCV-4D C1D2

Originally Posted by Chiller Guy

There are a lot of charts. What model are you looking for?