Recent content by Teto

Quark, Please explain the catch the water in the bucket method. Thanks, Teto

Hi all, I'm in a plant were circuit setters on air handlers were not always used (hand valves instead throttled down). THe problem I have , aside from balancing, I can't tell how much flow is running through a coil. I can contact the coil manufacturer and give him the Delta P and he can run...

A couple more items to add to my last posting: There are 4 relief valves on the system, all set at 45 psi. They can't all be failing shut. The present tank is a Taco CA215 full acceptance. Another question: In the worksheet I used, 5 parameters were required. Total system volume, minimum system...

All, Thanks for the input. Last week I started checking the size of the tank compared to the system volume. Using one manufacture's work sheet I calculated the size I would need. I've gotten one estimate for a replacement as the present tank came in low, in capacity. I'd like to use this forum...

This system has been in operation since 1997. All of a sudden we're losing bladders. No sign of oxidation on the air side of the bladder.

All, We've had repeated expansion tank bladder failures in our facility and I need some advice as to where to look for problems. It is a large volume tank (57 gallon, 215 L) on a hot water hydronic system. It is sitting on the floor and connected on the down stream of the hot water boiler and...

Ok, I'll use itsmoked's last equation for KW per hour. I understand now that when I fiddled with Excel, I ignored the change in other parameters therefore the confusion on PF. :~/ Thanks to all [medal], I always appreciate all the postings on this forum. Teto

I LOVE THIS FORUM!!! LionelHutz's approach makes it so much easier. So would it be applicable between single and three phase? I worked a few scenarios and the KW was not that much different. Thanks Teto

Keith, I was using the name plate rating of RLA . There is no FLA on the tag. It is an air conditioning unit. I was trying to furnish an idea on the cost of operation for the customer on a worse case scenario. So then, should I calculate HP first with: Hp=(V*A*Eff*Pf*1.73)/746 then calculate...

Hi all, I'm here from the mechanical side. Need help on understanding power consumption on a 3 phase induction motor. I was trying to calculate electrical cost of operation on a 3 phase induction motor. I used the formula Kw=V*A*1.73*PF/1000 for my calculations out of a electrician's pocket...

Thanks for the input above, Sorry it took so long to respond, I do appreciate the interest. The box manufacturer is Metalaire series 400 air terminal. It has an optional hot water coil. The hot water coil has a pneumatic control valve and the damper actuator is also pneumatic. The controller...

Thanks for the input. Another question on the same subject is: what is the "normal" duct main trunk pressure for such systems? I'm talking upstream of the VAV. How is it calculated? Is it based on the total of the max air flow through each terminal? Read any books on the subject? Thanks, Hector

Hi All, I have a Carrier 23XL, water cooled screw chiller with a glycol/water mix and a setpoint of 35 degrees leaving chilled water. It has digital controls (LID). My question pertains to the settings on the hot gas bypass. Add to that, the screw loads and unloads. I have experience with other...

I have a question pertaining to VAV system operation/setup and would value your comments. First some background:I operate an 8 year old building with a VAV system. The AHU units have variable air volume controls on the fan (inlet vanes controlled by duct static pressure controller to 2" wc) and...

timelord, Many years ago I proposed doing the same thing (using an HVAC unit rather than a commercial refrigeration unit). Although it will work the problem is that to achieve 60 degree air, the refrigeration apparatus will go below freezing at the coil surface. HVAC units are not made for this...