Lightning McQueen wrote:Our evaporative is shit, we have an inspection tomorrow so I'm meeting the agent there to point it out to her as I sure as f*** aint getting on the two storey steep roof to inspect it.
I'm going to suggest not renewing my lease because of it, it's a luxurious house with evaporative, what a let down, I can't remember what it was like during last summer unfortunately.
For 90% of our dry summers swampys do the trick, especially in older brick / double brick homes.
More modern places that are brick skin and gyprock internal walls get hotter quicker ( cool down quicker ) and, if not designed right can feel like they're not working at all.
The net effect is you turn the unit up higher, open more doors / windows to get the air flowing and eventually just bring more hot outside air in.
I think it's because of the high humidity we're enduring makes it seem fruitless.
I've been trying to research the ideal air flow for evaporative, need to work out how much of the doors need to be open etc.
A good evaporative should only struggle with humidity once or twice a year at the most here, we sometimes went years without having an issue. There's virtually no humidity today and it's the same for most of the summer. Evaporatives are the best value wise especially in Adelaide, I was amazed how much refrigerated air con cost when I lived at Prospect, better once or twice a year but you're paying major bucks to cater for those very few days.
Armchair expert wrote:Such a great club are Geelong
Wedgie wrote:A good evaporative should only struggle with humidity once or twice a year at the most here, we sometimes went years without having an issue. There's virtually no humidity today and it's the same for most of the summer. Evaporatives are the best value wise especially in Adelaide, I was amazed how much refrigerated air con cost when I lived at Prospect, better once or twice a year but you're paying major bucks to cater for those very few days.
I'll see when I get home, last year was by far the most humid summer that I can ever recall, I'm fine with the heat but the humidity stuffs me about and I remember struggling with it last year.
Lightning McQueen wrote:Our evaporative is shit, we have an inspection tomorrow so I'm meeting the agent there to point it out to her as I sure as f*** aint getting on the two storey steep roof to inspect it.
I'm going to suggest not renewing my lease because of it, it's a luxurious house with evaporative, what a let down, I can't remember what it was like during last summer unfortunately.
For 90% of our dry summers swampys do the trick, especially in older brick / double brick homes.
More modern places that are brick skin and gyprock internal walls get hotter quicker ( cool down quicker ) and, if not designed right can feel like they're not working at all.
The net effect is you turn the unit up higher, open more doors / windows to get the air flowing and eventually just bring more hot outside air in.
I think it's because of the high humidity we're enduring makes it seem fruitless.
I've been trying to research the ideal air flow for evaporative, need to work out how much of the doors need to be open etc.
If you like I can loan you an anemometer to check air speeds in the occupied zones?
Basically for you to feel cooling you need to have an air speed of over 0.5m/s of moisture laden air to be hitting your skin. The threshold of human skin for the perception of air movement is 0.25m/s. Under 0.25m/s you simply can't feel it. Under 0.5m/s and your evap won't feel like it's working.
A rough ( as it isn't really the way things work ) rule of thumb is the window/door opening should be about twice the size of the diffuser supplying the air into the room.
Ultimately an evap will only work so well up to a certain point when it comes to relative humidity.
Booney wrote:Ultimately an evap will only work so well up to a certain point when it comes to relative humidity.
I remember a building science lecturer banging on for hours about Swampy's seem to recall they start to lose their efficiency when the wet bulb temp is approaching 40 degrees. By 43 they are useless as water can't cool air that is any hotter than that......
Booney wrote:Ultimately an evap will only work so well up to a certain point when it comes to relative humidity.
I remember a building science lecturer banging on for hours about Swampy's seem to recall they start to lose their efficiency when the wet bulb temp is approaching 40 degrees. By 43 they are useless as water can't cool air that is any hotter than that......
Spargo wrote:We’ve got four bedrooms upstairs in a two storey with ducted evaporative & had no issues, touchwood...
They've progressed significantly over the last 3-5 years with energy and water efficiency.
How old is your unit?
Old. The temp control is a manual dial I’d say 20ish years old. I’m actually having it looked at shortly just to make sure it’s running at full effectiveness.
2017 safooty NFL tipping champ
2024 champ, Spargo’s Good Friday Cup @ Ascot
Booney wrote: If you like I can loan you an anemometer to check air speeds in the occupied zones?
Basically for you to feel cooling you need to have an air speed of over 0.5m/s of moisture laden air to be hitting your skin. The threshold of human skin for the perception of air movement is 0.25m/s. Under 0.25m/s you simply can't feel it. Under 0.5m/s and your evap won't feel like it's working.
A rough ( as it isn't really the way things work ) rule of thumb is the window/door opening should be about twice the size of the diffuser supplying the air into the room.
Ultimately an evap will only work so well up to a certain point when it comes to relative humidity.
Cheers, you may have to dumb it down for me a bit LOL.
I'll dick around with the doors etc. in the mean time using your ratio, I've been scabby about leaving it on but for memory my electricity bills weren't ridiculous last summer and it was left on pretty much all of January.
heater31 wrote:I remember a building science lecturer banging on for hours about Swampy's seem to recall they start to lose their efficiency when the wet bulb temp is approaching 40 degrees. By 43 they are useless as water can't cool air that is any hotter than that......
^ this. Had a small evaporative ducted unit in a double brick house a few years back. It worked fine in warm weather but not at all in hot weather (over about 35). There's only so much you can cool hot air by bubbling it through water.
Booney wrote:Ultimately an evap will only work so well up to a certain point when it comes to relative humidity.
I remember a building science lecturer banging on for hours about Swampy's seem to recall they start to lose their efficiency when the wet bulb temp is approaching 40 degrees. By 43 they are useless as water can't cool air that is any hotter than that......
Stayed awake through that one? Well done!
Also learnt that SA is an ideal place to use Evaporative Cooling!
It was his 'Embodied Energy' spiel that put me to sleep.......
