# Thread: Sizing chiller piping

1. What flange said is correct. I guess we need to clarify which system you are talking about because you need two pumps, one for you closed loop chiller-heat exchanger loop and the other to pump your tank through the other side of the heat exchanger, which is an open loop.

A centrif. pump is fine for the closed loop. For the open loop you need to make sure the pump has enough suction head so it doesn't starve. This is just like when you have cooling towers and condenser water pump all on the roof. The pump can really have a tough time if the sump level is not high enough above the pump. You can maybe make a pit for the pump but however you slice it this is something to figure out before you get her all piped out and can't get the open loop side to flow Especially if you go up and over the side of the tank, hmm maybe you could even put the pump into the tank, sump pump like!

Good luck with it

2. From what I can gather the tank is thirty inches high and is full of water and sits on the ground.
The pump will come off the bottom of the tank and also be low.
It should always have that 30" of water above it, so I think I should be good.
I went with lower chilled water and smaller heat exchanger. I went shell and tube so that I can clean it.

3. Professional Member
Join Date
May 2004
Location
Caldwell, ID
Posts
395
Post Likes

Keep it simple, you may be able do this with one pump.

You haven't given enough information to size the chiller. The previously provided calc that came up with 32 tons was incorrect.

What is the load that is making the tank hot?

If this an industrial process, there must be some other pump supplying this water to equipment needing to be cooled.

Is this a batch process? If so, you need to find out
Starting Temp(T1)-
Ending Temp(T2)- 90F according to your
Mass of water-1000 Gallons = 8350 lbs.
Time- This is the most critical factor

Equation: mass of water * (T1-T2) * (1/time)

Assuming T1 = 120 F and time =1 hour

8350*30*1 = 250,000 BTU/HR

Make it 2 hours and you cut in half.

If you are dealing with high temps like this, the least you would have to do is have a 3 way valve to temper the return water. If you are in a lower temperature range, you may just be able to put your pump by your tank and pump it to the chiller and back to the tank. You wouldn't have to mess with expansion tanks, buffer tanks, dual pumps and all of that.

Again, really high temps, strange chemicals in the water, really dirty water, etc. you may want to go ahead with with two separate pump loops.

Have fun.

4. I was given some of the calculations.
The tank of water has in one hour a 25ton load. The people I am sizing this for wants me to put in a 30 ton chiller. They are getting 32 tons.
I gave them the option of putting process water directly into the chiller but they didn't go for that.
I also said that they could put in a three way valve to maintain temperature in the process water but it doesn't need to be really close and they want to cycle the pump.
For the most part it will run all day long so I am not too concerned.
Thanks for the comments!

5. Professional Member
Join Date
Jul 2007
Location
south bay california
Posts
202
Post Likes
An engineer is having you size up the piping, are you getting paid for your engineering? Are you assuming liability of the equipment once you pipe it in?

6. How is sizing piping engineering?
I am getting paid if the job goes through. I might say something if I don't do the job and they ask me to do another one, but as of yet I will not do anything.
We are going to give a standard one year warranty.

Page 2 of 2 First 12

#### Posting Permissions

• You may not post new threads
• You may not post replies
• You may not post attachments
• You may not edit your posts
•

## Related Forums

The place where Electrical professionals meet.