IRstuff raises a good point, does the hotel has any means to monitor room occupancy? (and integrate into room temperature controls)
I have occasionally seen the keycard used to deactivate lighting but I've never seen it deployed to put AC on a unoccupied set back. possible though no doubt.
In more basic terms, think about regenerative braking in an electric car. the wheels are slowed down when the EMF generating motion is removed, since the wheels are (initially) still rotating they generate a "back-EMF" in the motor windings which is used to push regenerate some change back in...
What sort of vibration are they saying it was? internal vibration on the machine? Was the chiller installed with vibration isolation? did the rotating/reciprocating chiller components have vibration isolation? is the manufacturer recommendation to vibrationally isolate the chiller?
What was...
in my jurisdiction, the requirement for needing to provision make-up air was if the KEF is over 400 CFM.
If I were you I would select a 400 CFM KEF like I did. We never run KEF past 2/3 speed so I've never had any flow issues.
you could also have some leaky ductwork or or maybe some vents open off the system to other areas? in my house we have a furnace for the 2nd level which also has some grilles in the basement. I have to close these down in the summer to make sure the cooling goes where it is needed.
it sounds like you may be getting regenerated noise off the grilles or maybe through some torturous duct design. maybe as a test you could remove the grille and see if the noise stops, if it does then you might be able to re-select for a higher free area grille to achieve the same design.
Questions:
What temperature is set to 24C? the supply temperature or the room temperature?
Are all pieces of equipment operational?
what is LAT off FCU?
Where is the FCU pulling from?
possible issues:
[ol 1]
FCU could be malfunctioning, either not blowing or cooling. Either of these would...
As Willard states, a product specification will normally call out the required documentation, as a baseline, follow this format. Larger projects will have a set of general requirements specifications which will include submittal requirements. For specifications that follow the AIA Master Specs...
We normally have delegated design verbiage within our specifications, putting the onus on the contractor - if it works with timing this is probably your easiest approach. In my experience the local contractors understand the requirements intimately as they have to deal with them on every...
Good point above, but I wouldn't treat the catalog performance tables as worst case - these are just at common/standard design conditions which may be more or less stringent than the design need.
Always get a selection from your rep at your design conditions.
What voltage are you getting at the chiller/components? perhaps the integrity of the electrical connection was compromised leading to low voltage/high current?
According to Britannica:
At those temperatures, rejecting from the heat sink to atmosphere should be no problem, the household AC might be running a little hard though. [wink]
most manufacturers typically have a threshold below which they don't de-rate. Typically around 3000 ft. anything above this and they should most definitely de-rate.
According to this website they are basically the same, they have a slightly different composition & are manufactured to different standards (EU vs US I assume)
https://www.fastenal.com/products/attribute/600173/5;jsessionid=202C597BAB6E1291E073818CBE01A41B.jvm3
Variable Primary is a thing. You will want to have a minimum flow bypass in the loop somewhere to ensure that you can pass minimum flow through your chiller. The minimum flow will be dictated by the chiller manufacturer and will me ~40-50% of the chiller nominal design flow. Note, the "chiller...
Depending on the size of the room and the amount of refrigerant in the largest circuit you may need to treat the room as a machine room which dictates exhaust rates and operation. Refer ASHRAE 15.
