I was working for a static complex (5 buildings) that had their own permanent chiller engineer and controls engineer (me).
A few years after I left and was working mobile I was called to a site...
Type: Posts; User: only1doug
I was working for a static complex (5 buildings) that had their own permanent chiller engineer and controls engineer (me).
A few years after I left and was working mobile I was called to a site...
As has been noted, you need to give more information about what you need to get a good reply.
I'll assume that your question is about Energy efficiency implications of adjusting chilled water flow...
We have the reverse situation, Some of my customers are convinced that the Thermostats are Dummies which "don't do anything" even though they operate correctly.
Another area (recently) told me...
That is so very true.
I may just have to take that as my signature.
6000' altitude, I hear that the air is considerably thinner up there.
It may well be that there aren't any problems with the switch, just with the unit. Increasing the size of the intakes may help...
To Clarify (not that i feel defensive at all :P) I wasn't suggesting adding RAM as a solution, my recommendation was also to clean up the PC.
With Wye Delta startup (or what I call star delta) you are changing the motor terminal connections between 2 configurations so you need to have 2 contactors that MUST not both be energised at the...
No, its interfering with a emergency services repeater mast.
Police, Ambulance and Fire Brigade...
We original thought it would be the AHU inverters again (occurred before and inverter was...
Hi All,
Had a visit From a Frequency Engineer from Ofcom, We apparantly have an interference source on one of our roofs.
The roof in question has 2 Air Handling units each with 2 supply and...
I can answer that one for you, Best to take it in for a tune up.
No removing Pics and music won't fix the problem (but you should do so anyway) as they are on your hard drive not in RAM.
The...
Post Ultimate deterrant warning signs:
<top caption>"this building guarded by:
HillBilly Justice"
<picture of a HillBilly in reclining chair next to a RTU with empty beercans scattered around...
PLC: Programmable Logic Control isn't often used in buildings as it isn't very well suited to analogue applications such as temperature, humidity and pressure.
Sounds very good to me.
If you think you can live without cooling then try to avoid it.
One of the problems associated with modern residential airconditioning systems is Dirty Sock Syndrome...
Will DEFINATELY get you sued by the survivors (or their Heirs if they don't)
Flange is right.
Pressurisation fans are to ensure that safe zones and access to them are kept clear of smoke, they do this by supplying more clean air than the smoke extract's are removing.
If...
If the wire is placed so that it is clearly visable and they decide to enter it anyway they would have a hard time suing. If the wire is placed so that it is hard to see and they get cut because they...
More details needed about controls system fitted.
You may have missed the point John, the OP (original poster) is of the same opinion as everyone else, the trouble is he has to try to comply with the request of the energy savings engineer. The OP is...
I'm guessing your Heat pump is outside, Is it hot (I mean really hot!)
The reason I ask is that 8KW is a lot of energy, on the same scale as having two Large electric fires (4 bars). Energy useage...
6000 KWh / month? umm
(quick math time) 6000/30/24=
wow, thats 8KW / hr... are you sure the landlord hasn't tapped off the supply to feed a marajuna farm or something...
I'd expect you to...
Hi MrsPappy,
As Skimbe says the filter placement is less than optimal, Exterior filtration is preferred.
As you noted the "permant washable" filter can be cleaned by vacuuming, be careful when...
What is the problem? I'm guessing its that the occupants get too cold?
overall building design when using VAV units is often to maintain a constant supply temp and then have the VAV's shut right...
Consider yourself Lucky Osiyo, the complex i work at is a 24hr building (there really are people in there all the time) and someone decided that chilled beams were the optimum energy efficient way of...
sample 5 was missing
Using GX9100 to edit the datafile you will see something like image GX9100 sample1 right click on your timer program module (sample2) and click DATA (sample3).
Find an empty timer block (type set...
How accurate could we make a BACnet rooftop weatherstation?
Barometric pressure sensor, Outside Air Temp & Humidity, Wind speed & direction indicator, Luxmeter (for cloudcover calcs)...
Would we...
Add a software Timer module.
What software are you planning to use to communicate with the PXC52?
The Machine itself is probably worth nothing but scrap iron value But as they have banned making old refrigerants the recovered refrigerant could be fairly valuable.
The hospital in South America...
From Manual.
"The Network Display Panel (NDP) is a user-friendly operator interface which
can be connected anywhere on a Trend network (except on an internetwork) via
a node controller, or...
Please find attached M_NDP.PDF (Network display panel Manual)
Hi Stanbyyourword,
The NDP (Network Display Panel) can only drive the outputs via the Knobs and switches within the control strategy, there is no option with an NDP for overriding outputs.
I'll...
I Concur, Do the work now and be ready for when the specified controls strategy fails to work.
#7 please: immortality would be bad but 160 years of invulnerable good health sounds ok to me.
Sounds like a perfect design, Installed upside down.
I don't see this as requiring the use of valve feedback positioners, the DDC system will already know how open the valves are without the positioner, if the valve doesn't open when asked then you...
http://openpub.realread.com/rrserver/browser?title=/ASHRAE_1/ashrae_90_1_2010_IP_1280
Page 51, section 6.5.4
"where differential pressure control is used to comply with this section and DDC...
Once you have done your design step away from it for an hour or two then go back and look at it from the perspective of a prisoner: What could I break to mess things up or make into a weapon?
I'd Agree with Tristar; VRV is probably the best solution for your application.
As Crab said: Use DP sensors to control Pump speed, not valve position.
With Large pumps you will get enough of a saving from soft start alone to justify the inverters. (And longer pump life as an...
by offset bumpkin is referring to the amount of correction he would need to apply to make the sensor "appear to be" calibrated correctly.
Measured temp with calibrated sensor - BMS sensor reading...
Unfortunate, It resolved my issue, which had been JCI Metasys DX controllers, the USB lead worked intermittently and the Express port lead worked every time (until shortly after my 2 year old...
The 2nd biggest hurdle is how to automatically import the forecast data into your BMS system in a useable fashion.
The biggest hurdle is getting a reliable local forecast.
As it seems that your fan will take awhile to slow down (Must be a big fan!) you might want to consider ways to keep the damper open.
If the damper is opened by the fan run signal then consider a...
I also had this problem, connecting via USB to a serial port.
I got a Express card serial port and it worked first time.
Using the Express card (once known as PCMCIA) creates a true serial port...