Looking for aircon recommendation.

beveragelady

If this is in the wrong forum let me know and I'll ask the mods to move it.

I have been given very good advice by boardsies in the past and I'm back for more!

I work in a large classroom, one wall of which is mostly windows. The old windows were replaced a few years ago with very fancy glass that heats up when the sun is out. If there's snow on the ground outside the windows are still acting as a giant radiator, so it's not really anything to do with outside temperatures.

The room can reach temps in the mid twenties before lunchtime. Add thirty teenagers and it becomes unbearable.

I have tried every combination of opening doors and windows and messing about with the blinds but for various practical reasons there is no solution there. I have two fans going most of the time, with 2L bottles of ice behind them to try to move cool air around.

I'm told built in aircon is out of the question but I have been given the go-ahead to get a portable aircon unit and I'm looking for recommendations.

Here's what you might need to know:

1. The room is large with high ceilings. I'm useless at estimating measurements but it's probably one and a half times the size of an average classroom. (I'll measure it tomorrow.)

2. I can vent it out a window or I can drill through the PVC panels of the exterior wall.

3. Portability is not really a problem, so it can be as bulky as it needs to be. I don't care if it's ugly either.

4. Noise is a consideration but not a dealbreaker.

5. Humidity is not a problem so I don't need a dehumidifier.

6. The better the price the easier it will be to get it past management.

Please help! We're not a nation of aircon aficionados but any scrap of helpful info would be great.

This is what I'm looking at currently: https://www.amazon.co.uk/Igenix-IG9903-Portable-Conditioner-Function/dp/B01G7L483U/ref=cm_cr_arp_d_product_top?ie=UTF8

xl500

Well First of all for an average Classroom that size of unit you linked to will not be large enough

Get the size of room and convert to Volume and go online to size unit

But considering how often you use it I presume the classroom is unoccupied during Summer Months

Have you considered External Shading

Internal Shades will not work as Sun still hits Glass but External Shades could be very effective

beveragelady

Sorry, I should have added that I envisage more that one unit in the room.
I'm told external shading is not an option, and various external window coatings aren't feasible either.
Also, as I said in the op, outside temperature isn't the issue. If the sun is out at all there's a problem, even in mid winter.

xl500

beveragelady wrote: »

Sorry, I should have added that I envisage more that one unit in the room.
I'm told external shading is not an option, and various external window coatings aren't feasible either.
Also, as I said in the op, outside temperature isn't the issue. If the sun is out at all there's a problem, even in mid winter.

The Reason I advised Outside shading was nothing to do with outside Temperature and all to Do with Solar Gain

Dardania

Can you apply a film to the external of the windows to prevent sun penetration? Doesn't have to be completely darkening - just partial.
see this: https://www.windowfilm.co.uk/commercial/heat (and maybe you can find an Irish equivalent)


Air conditioning is a reactive solution to the problem which has some side effects that are unpleasant e.g. could dry out the air. As xl500 suggests, preventing the problem from occurring in the first place by shading externally would be best.

Sleeper12

Something worth thinking about is that the noise from a stand alone air could unit is considerable. I bought one my 3 years ago for a are 400 euro. We have never really used it due for noise.

antoinolachtnai

The coatings or film are the way to go. The core problem is solar gain.

The amount of heat that 30 youngsters generate is pretty large (maybe 3kW) before you even talk about the windows. When that sun hits the window, it will generate an awful lot of heat, and as you say, the external temperature has very little to do with it.

This crowd (and there are others) will supply a suitable film.

http://www.advancedwindowfilms.ie/commercial-window-film-applications/

This is quite a common problem. These types of coatings are used all the time.

If you do air conditioning, you're going to be fighting all this heat generation. There is just going to end up being a lot of noise. You are going to have a significant electricity bill too.

The great thing about the coating/film is that you put it on once, and that's the end of it. No electricity bills, maintenance or noise.

Stheno

Sleeper12 wrote: »

Something worth thinking about is that the noise from a stand alone air could unit is considerable. I bought one my 3 years ago for a are 400 euro. We have never really used it due for noise.

This. I work in a place with a standalone unit and you need to nearly shout to make yourself heard

wordofwarning

beveragelady wrote: »

Sorry, I should have added that I envisage more that one unit in the room.
I'm told external shading is not an option, and various external window coatings aren't feasible either.
Also, as I said in the op, outside temperature isn't the issue. If the sun is out at all there's a problem, even in mid winter.

Why is outside shading not an option? In thes like of Spain and Germany, they have external shades to keep the sun out. Which keeps offices, houses etc cool.

You could get automatic shutters

antoinolachtnai

I can see that it would be quite expensive to make something that was sufficiently strong to resist the environment and vandalism.

Dardania

planning permission also probably required - not impossible to overcome but adds another wrinkle

@OP: Do you have northern skylights in these classrooms, in addition to the troublesome glazing?

beveragelady

wordofwarning wrote: »

Why is outside shading not an option? In thes like of Spain and Germany, they have external shades to keep the sun out. Which keeps offices, houses etc cool.

You could get automatic shutters

Unfortunately I'm not the one calling the shots or footing the bill. I've been told that anything external like shutters, shading or film aren't feasible. That seems to be that.

Dardania wrote: »

@OP: Do you have northern skylights in these classrooms, in addition to the troublesome glazing?

No, it's just windows and a door onto an unventilated corridor.

xl500 wrote: »

The Reason I advised Outside shading was nothing to do with outside Temperature and all to Do with Solar Gain

You mentioned the summer months so I wanted to make it clear that this is a year-round problem.


Back to aircon... It looks like the noise factor is significant. I really don't need another reason to raise my voice in class so I might have to reconsider this idea. In the meantime I'll keep lugging bottles of ice into work with me.
Thanks for your input everybody.

Pete67

There are solar films which can be applied internally, avoiding the cost of exterior scaffolding etc. This would be the most economic way to significantly reduce solar heat gain, and would also reduce glare on sunny days. The cost to treat one room would not be significant.

See here for example.

Dardania

thinking further on this OP, if you can encourage air movement out of the room (e.g. via the coridoor to somewhere else) it would be a good solution also to get rid of the heat.

I used live in a single aspect apartment in Dublin, and would occasionally open the window at the end of the central building corridor when I wanted to vent out the apartment after cooking