Door Fan

[Mannymalistic]

With the outbreak of Dengue fever in several islands I've been thinking about ways to minimize flying insect intrusion into Philippine homes. Many restaurants here were I live is the door fans wherein an "air curtain"in is created with the overhead fan kicking on when the door is opened.  Has anyone done this over there? Is it feasible? Is it effective?

[lost_in_samoa]

Is it feasible? Is it effective?

Might work.  We sleep with ceiling fans and that keeps most of the little buggers off of us.  Most that is.

Just some thoughts.

Fans take a bit to spin up to speed.  If it is on a door activated switch will it be spinning in the time frame someone is transiting the door?

If you putting positive air pressure on the door frame, you are sucking air through somewhere else.

You could try to move enough air to pressurize the whole house.  We had an 5' attic fan in the states that would do that.  But you would need to be sealed up pretty good.  Doing that might give you more heat and mold problems than it is worth.



How about a good quality colombo and a couple of small personal fans under it to keep the air moving?  Might be a more practical solution.

HTH

[Mannymalistic]

Surely from an energy consumption standpoint, the Colambo is superior.  In my experience there though, if the ‘squitoes and langao are already in house, they can also sneak into the colambo when you climb in.  Sanitation departments here require air curtains at food facilities because they can be close to 100% effective in keeping bugs out of the inside environment.  The ones I’ve seen installed at grocery stores and restaurants seem to spool up quickly, maybe within 1 second.  As for the vacuum it might create, they can apparently be installed external to the door.  I’d have to dig in further to verify this manufacturer’s claim that air curtains serve as an effective barrier between the internal and external environments thus preventing the escape of conditioned air to the outside as much as 75% whenever the door is opened.

Now all this info is from the makers of these devises and sounds quite rosy but it appeals to my common sense that disrupting the air will whip these bugs around big time and keep them from entering.  Your experience with the common ceiling fan bears this out.  From the sanitation, disease transmitted/Dengue point of view this solution appeals to me. Of course the house has to be screened to support it’s effectiveness. On Amazon, they can be had for around $250.00  Question is, why isn’t this devise more widely used there? 

[lost_in_samoa]

Question is, why isn’t this devise more widely used there?

Don't know.

Amble on down to the bario jueteng shed and ask around.  The answers ought to be entertaining.

[Mannymalistic]

Ah yes, the jueteng sa kanto.  Will do!

[Hank]

.. if the ‘squitoes and langao are already in house .. it appeals to my common sense that disrupting the air will whip these bugs around big time and keep them from entering. From the sanitation, disease transmitted/Dengue point of view this solution appeals to me. Of course the house has to be screened to support it’s effectiveness. On Amazon, they can be had for around $250.00  Question is, why isn’t this devise more widely used there?

Regarding dengue, your door fan suggestion might seem a reasonable idea anyway. But, perhaps one reason why fans are not more widely used might be that in a country of a hundred million, in most provinces the dengue infection rates are only eleven cases per day over the first six months this year. (<2,000 cases). Also, except for one or two areas, the death rate from dengue is less that 30 people per province over the full half year. I guess people think it's worth the risk anyway?

For example ...

[Mannymalistic]

Nice map. It would seem like the odds are fairly low in Luzon, relative to the Visayas. It seems like the door fan would still be desirable to keep out flies.  Theyre just nasty little guys that contaminate everything they land on. 

[Peter]

..... On Amazon, they can be had for around $250.00  Question is, why isn’t this devise more widely used there?

Unsure of what device you are referencing, but I assume it is a door fan of some description, as this is the subject matter.

The Philippines has one of the highest, if not the highest, electricity tariffs in east Asia, as well as extreme poverty. So that, IMHO, may be the primary reasons for the procurement and operation of door fans being beyond the reach of most 'Juan sa kalye'.

Some companies or individuals may have them installed in their premises, but in the last 10 years we've been here, I've only seen two installed. One in a high end restaurant entrance, the other in a warehouse.

Not to say there aren't others, but we haven't come across them (yet?).

Peter

Edit. I should have mentioned that in both instances the fans were installed in an enclosed space, between the entrance door and the door to the premises proper and I can't remember if they were "suck in" or "blow out",   

Peter

[Mannymalistic]

Just to clarify, the fan I refer to is a long squirrel cage type above and at the width of the door frame.  It blows a “curtain” of air downwards thus creating a barrier of wind that prevents bug entry.  The devise neither adds pressure nor vacuum to the interior of the house.  For home use, it would turn on when the door is opened to enter and turns off once you’re through the door or screen that just closed behind you., all of about 7 second maybe?  Although electricity is very expensive there, I would think that the short run time would add minimal cost relative to the current draw of other home appliances like an A/C for example. Of course affordability would be prioritized accordingly.

[Peter]

Just to clarify, the fan I refer to is a long squirrel cage type above and at the width of the door frame.  It blows a “curtain” of air downwards thus creating a barrier of wind that prevents bug entry.  ................................

Thanks for the equipment clarification, Manny.

Most families in our Barangay, have monthly electricity bills of around PhP 1,700.00 to 2,300.00 (according to the wife) when running just one or two fans in conjunction with lights, a fridge and a TV. The running cost of an additional large fan set above an entrance door, would be hard to justify. If they could afford the US$ 250.00 or so, procurement price that is.

Most Filipino homes I've been in, do not have A/Cs, although we have them fitted in all 4 bedrooms in our home. The price of a single 0.75 HP A/C is around PhP 13,000.00 and the monthly individual running cost is about PhP 1,500 for 12 hours nightly use.
A purchasing price that is probably out of reach of an average worker, let alone the operating costs..

As our Barangay is typical of the Bataan/Pampanga area, I would hazard a guess that other areas will be similar in cost of living and employment remuneration.

Of course, as we are all rich millionaire foreigners,  then we would be able to afford it! Or not LOL!

Peter

[MotorSarge]

Unsure of what device you are referencing, but I assume it is a door fan of some description, as this is the subject matter.

The Philippines has one of the highest, if not the highest, electricity tariffs in east Asia, as well as extreme poverty. So that, IMHO, may be the primary reasons for the procurement and operation of door fans being beyond the reach of most 'Juan sa kalye'.

Some companies or individuals may have them installed in their premises, but in the last 10 years we've been here, I've only seen two installed. One in a high end restaurant entrance, the other in a warehouse.

Not to say there aren't others, but we haven't come across them (yet?).

Peter

Edit. I should have mentioned that in both instances the fans were installed in an enclosed space, between the entrance door and the door to the premises proper and I can't remember if they were "suck in" or "blow out",   

Peter

Okay I now know what you are talking about..I have seen these in newer military chow hall entrances.

[Mannymalistic]

Thank you Peter for the cost comparisons of fan vs A/C.  You are probably right about the expense not affordable to the majority of Filipinos.  For myself then, considering the energy costs you’ve cited, I would still give serious consideration to the “door wind curtain” because I’ve come to believe that anything I can do to reduce the chance of insect transmitted disease is an enhancement to my health.  Thank you folks for the information you provided.

[Frosty]

I've seen these in Los Vegas. it's like an air dam they keep the hot air outside and the cool air inside.
they seem to work very well for that application.
I don't know how they work with bugs.

[MotorSarge]

I've seen these in Los Vegas. it's like an air dam they keep the hot air outside and the cool air inside.
they seem to work very well for that application.
I don't know how they work with bugs.

They work...using a moderate force of downward/outward shot of breeze upon door opening....most flying pests can't overpower it.
For bugs...use grenades!

[Mannymalistic]

That’s exactly it, Motor Sarge. For a tiny insect that’s got thin tiny wings, the ‘squito and fly cannot penetrate the air turbulence and just get blown out if they fly into it.