Control Valves on the Supply or Return Chill Water System?
Control Valves on the Supply or Return Chill Water System?
(OP)
My drawing indicates the Honeywell 3-way modulating Control Valves on the Supply side (modulating the return side), shouldn't the Valve be on the Return Side for Chiller Water and Hot Water System? I thought it was a drawing error. Would that effect the flow efficiency if it's located on the wrong side?
Thank you in advance.
Thank you in advance.





RE: Control Valves on the Supply or Return Chill Water System?
Let's see what the experts say.
RE: Control Valves on the Supply or Return Chill Water System?
Diverting valve on the supply side.
Mixturing vale an the return side .
Pardal
RE: Control Valves on the Supply or Return Chill Water System?
Diverting valve on the supply side.
Mixturing valve an the return side .
Pardal
RE: Control Valves on the Supply or Return Chill Water System?
Regards,
Eng-Tips.com : Solving your problems before you get them.
RE: Control Valves on the Supply or Return Chill Water System?
"A mixing valve is always installed on the return line and a diverting valve on the supply line. Though both installations are technically correct, it is better to use mixing valves(on return line)."
** Please define mixing or diverting.
"The advantages are that, you can always ensure your coil is totally filled and also as the return temperature is higher you will have less problems with valve body sweating."
** What happen if valve body sweating, what consequences?
THANK YOU
RE: Control Valves on the Supply or Return Chill Water System?
And the diverting valve is more expensive than mixing.
I dissagree about sweating , the return water will be always under the dewpoint of air , so it will allways sweat.
When instaling you shall locate the actuator preferible on top or by the sides , never on the bottom , because sweat water will damage the actuator.
Pardal
RE: Control Valves on the Supply or Return Chill Water System?
Diverting Valve - Which diverts one stream flow into two stream flow.
The links below will give you good understanding and selection procedures.
http://www.spartan-pd.com/PDFfiles/Piping.pdf
http://www.belimo.com/IMS_DOCS/56/56189BE43C17984A862A4...
http://www.belimo.com/IMS_DOCS/21/21BD69054E68674C8BA60...
Disadvantages with sweating.
1. Energy Loss (latent heat from condensing moisture is transferred to chilled water) - Superfluous
2. May corrode your system slowly - Most Likely
3. May cost your job - If you are in a Pharma Company
4. You may have to arrange for floor cleaning frequently - Obvious
Pardal!
I agree with your disagreement (huh... so kind of me
Regards,
Eng-Tips.com : Solving your problems before you get them.
RE: Control Valves on the Supply or Return Chill Water System?
Pardal
RE: Control Valves on the Supply or Return Chill Water System?
I think , statement "A mixing valve is always installed on the return line and a diverting valve on the supply line" is not 'always' correct because there are applications which mixing valves used in supply line and diverting valve used in return line as can be seen at links quark's post.
first,proportional control valves should not be mixed with 2-position "3-way valve" , secondly the control logic must be considered (constant flow or cnst.temperature)and pressure drop for both sides of 3-way valve should be calculated to ensure the valve work properly. (if it is not equally ballanced valve may be %50 open but fluid flows ,lets say, %40 because it 'always' prefers the easiest way).Pump location should also be considered.
I hope , I dont 'mix' too much
Ercan