AHU supply air ducting water drop

[ah fai]

hello everybody

Ballroom ducting water drop when the room temperature around 21 deg C.

it is possible the trouble with bad insulation? and what is the solution??

thanks in advance.

[frank]

I would agree that it is possibly caused by condensate.

If the ducting itself is dripping then it would be down to poor insulation. If the drops are coming out the grilles then it is something else

Any ideas what the humidity levels are in the Ballroom?

[install monkey]

also drip tray on unit not draining, u bent not clear or installed wrong- dirty filters can cause water to get sucked off the coil- or as frank states, damaged or poor insulation,or humidty issues

[mikeref]

Thinking your ambient temperature and humidity is part of the cause. As you are smack bang on the Equator, and asking for 21*C is making your Air-conditioner work longer duty cycles.
Do the registers closest to doorways leak more than others?
Does this condition get worse when the ballroom is occupied?

[ah fai]

can u guy show me how to measure and calibrate the humidity in the room?

what is the issue if the ballroom is occupied or maybe not?? what is the different?

thanks..

[frank]

If the Ballroom is occupied then your humidity levels would increase, providing they weren't around 100% at the time :D

With an empty hall, the humidity levels would be lower than if you had people in there, as people give off vapour from sweat and breathing. Your air conditioning system has to deal with this water vapour as latent heat.

Humidity is the amount of water vapour entrained in the air. When the air cannot hold anymore water vapour, condensation starts to form. The point at which this happens is dependent on the atmospheric pressure and the temperature. Humidity is expressed (Relative Humidity) (RH) as a percentage and is the ratio of the actual partial pressure exerted by the water vapour in any volume of air to the partial pressure that would be exerted by the water vapour if the water vapour in the air is saturated at the temperature of the air.

Basically, the air becomes full of water vapour at a given temperature and cannot hold anymore vapour so it rejects it as condensate. The point at which this happens is dependent on temperature and atmospheric pressure.

Humidity cannot be calibrated. Do you know anything about psychometric properties of air ?
.

[Tesla]

Like mikeref posted 21degC is far too cold especially for your location - it would give most of us fripples. Frank has given a good detailed reason. I tried to give smileys but I have to spread them around.

[frank]

can u guy show me how to measure the humidity in the room?

To do this, you need 2 glass thermometers. Wrap a small piece of cotton wool or similar around the bulb of 1 of them and then wet it. Now shake off the excess water and leave both thermometers in the room...1 with a dry bulb and 1 with the wet cotton wool around the bulb. After half an hour, take the readings/temperatures and post them on here.

[ah fai]

ok, thanks a lot for info.. i am trying to do this first..

[ah fai]

I am not sure the type of glass termometer. if possible can your guy please post a picture...
thanks in advance

[install monkey]

https://www.google.co.uk/search?q=sling+psychrometer&hl=en&tbo=u&rls=com.microsoft:en-GB:IE-SearchBox&rlz=1I7WQIA_en-GBGB510&tbm=isch&source=univ&sa=X&ei=sYYOUbbmIsHJ0AWKzIDQAg&ved=0CD0QsAQ&biw=1366&bih=651

[frank]

https://www.google.co.uk/search?q=sling+psychrometer&hl=en&tbo=u&rls=com.microsoft:en-GB:IE-SearchBox&rlz=1I7WQIA_en-GBGB510&tbm=isch&source=univ&sa=X&ei=sYYOUbbmIsHJ0AWKzIDQAg&ved=0CD0QsAQ&biw=1366&bih=651#hl=en&tbo=d&rls=com.microsoft:en-GB%3AIE-SearchBox&rlz=1I7WQIA_en-GBGB510&tbm=isch&sa=1&q=glass+thermometer&oq=glass+thermometer&gs_l=img.3..0l2j0i5l3j0i24l5.35761.39438.0.39923.17.17.0.0.0.0.193.2245.3j14.17.0...0.0...1c.1.2.img .W6sIOoQIiL0&bav=on.2,or.r_gc.r_pw.r_cp.r_qf.&bvm=bv.41867550,d.Yms&fp=4d20f3fce009d132&biw=1920&bih=1075