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Tuesday, 8 November 2011

Portable Fume Extractor

When is a fan not a fan?  Or at least not a cooling fan!

There are other uses for fan technology, high pressure fans are used to inflate bouncy castles, and high pressure fans with good suction can be used as fume extractors.  Fume extractors are a common sight in woodworking shops but are often called dust extractors.  Of course they perform the same function, they work as a fume extractor by taking air which is full of a harmful particle and blows it out where it will do no harm.

It's worth knowing that you don't have to install a fully fitted integrate fume extraction system.  These fitted fume extractors are expensive to buy and maintain and can't be taken with you if you move premesis.  An alternative is a portable fume extractor, a portable fume extractor might make much more sense.  Portable fume extractors are inexpensive, efficient and suitable for most applications.

Our VF300 portable fume extractor is available in both 230v and 110v and is one of the best portable fume extractors on the market.

Monday, 3 October 2011

Which Portable Heater?

We're closing the cooling season in the UK now.  Again it's not been a great summer, the weather has not been great, but air conditioner sales have been good anyway.

With winter fast upon upon us, and seeing as how the previous two or three winters have been very cold and quite snow covered - it's time to start thinking about portable heaters.  Choosing the correct portable heater can be just as difficult as choosing the correct portable air conditioner, if not more so.

To that end, if you are thinking about  a portable heater, why not read through the Which Portable Heater Blog?

It's written in the same spirit as Which Air Conditioner, but covers the factors you have to consider when buying portable heaters and the various types of portable heater that you can buy.p

Tuesday, 16 August 2011

Portable Air Conditioners

Portable Air Conditioners are one of our most popular sellers, however we only really specialise in the big, industrial and commercial portable air conditioners.  Currently we get a lot of non-converting traffic on people searching for portable air conditioners, but why?

One theory is that the people searching are actually looking for the smaller, cheaper plastic portable ac units which are imported from China and sold in the likes of B & Q and Focus.

These units can retail for as little as £150 or less, and they do work, we used to carry a stock of these units and sell and hire them - however the market appears to have died.  The question is why?  The answer I'm guessing is the massive influx of cheap foreign units which are sold with very little margin making it a market not worth being in.

Are these units worth having?  Surely they're no good if that's the price?

Well, yes and no.  If you want some cheap cooling in a bedroom or living room then they're not bad and they're definately cheap - but a twin duct would be far better, because it draws fresh air in, and cools it  as well.  Cost wise we're going to be looking at closer to £1000 but it will perform far better.  For shops, offices and commercial environments it's all down to capacity.  If you run any AC unit in a room too big for it to cool or with too much heat gain for it to cool - it is only ever going to spot cool and never lower the temperature.  It may even damage the machine. 

In these instances, an MCM or an MCWCS unit is a better option.  Of course if it's a 6' x 6' office with a desk and and a single worker - then the £150 plastic, chinese option is probably going to be perfectly effective and should perform adequately.

Tuesday, 9 August 2011

More about me.

So apart from writing technical jargon about portable cooling who am I ?  What do I like doing?

Well, I spend a good portion of my spare time writing star wars fanfic on a star wars roleplaying board.  Which is good fun, though the board is a little down on members at the moment. 

I've been an avid  video games player for over 30 years and I have recently started getting into Lego, in particular Lego Design by me .

I also have a bit of a hobby in websites, I operate several information sites one on supercharging Mazda MX5's and MX5 Turbo.  There's one about taekwondo a martial art I have a second degree Black Belt in, but not trained for a while.

Then there's my site about house building which is based on personal experience of building my own house.  There's more actually... I have a lot of websites and blogs and things...

Thursday, 4 August 2011

Monobloc portable air conditioners cause negative air pressure.

There is a problem with monobloc portable air conditioners, these are normal kind of thing you buy with a tumble dryer hose on the back to pump out the hot air.

The problem is their efficiency.  Firstly, if you have a long hose passing through the room - it's going to radiate a certain amount of heat back into the room. 

Secondly, because of the 100% it draws in, being split into two halves, and one half being heated then pumped outside - they cause slight negative air pressure in the room.  What this means is wherever the room is not air tight, air from a neighbouring warm room will be pulled in reducing the cooling efficiency.

The easy way to tackle these problems is to use a water cooled split portable air conditioner such as the MCWCS250.  Sometimes this might not be practical or affordable though - so what can you do to reduce the problems?

Firstly, insulate the exhaust hose - particularly if it trails around the room, and have as little exhaust hose in the room as possible.

Secondly, think about where the air drawn in by the negative pressure is likely to come from - if there are two doors to the area and one leads to a cooler place than the other - consider openind the door to the cooler are and taping around the other door to seal it.  This will actually aid efficiency if the cooler area is sufficiently cool rather than harm it.

Given the high cost of running air conditioners, due to the big power requirements, it's important to have them running as efficiently as possible, and this can require an understanding of how the various types of unit work, and a little thought.

Wednesday, 3 August 2011

Cooling Fans - What NOT to buy.

If you're looking for a powerful industrial cooling fan, because perhaps the area is too large to cool with a portable air conditioner then you need to think carefully about what to buy. Many fans on sale from online shops look powerful, and look big but can only be felt if you're standing right next to them.

The key things to look for are multiple impellers, if it's only got 3 blades, it's going to be a very weak fan, look for at least 5 blades. Look at the wattage of the motor, if it's less than 150W then it's not going to be very powerful.

This video shows you the difference between a good and a bad fan. Both of them look powerful and industrial... Until you turn them on!

Thursday, 28 July 2011

Evaporative Coolers vs Portable Air Conditioners

So how does an evaporative cooler work? Well, essentially they work on the same principle as a cooling fan. The difference is, with a cooling fan it sort of relies on you being a little hot, and a little sweaty to work. Basically the air passing over a wet object causes the water to evaporate and this knocks about 5 degrees C off the temperature.

The way it does this is by adding humidity to the air, by dropping water over a filter and blowing that moist air back out.

So what's better? Well, you can run an evaporative cooler with the window open no problem, in fact it's a good idea to keep the window open as otherwise the machine is going to raise the humidity in a room to uncomfortable levels. They are cheap to run, there's only a little fan and pump to run so compared to portable air conditioners they are signficantly cheaper to run.

The downsides to the evaporative cooler are the raised humidity and the fact that you can never cool more than about 5 degrees from the ambient. Obviously the humidity means they can't be used to cool electronics and if it's over 25 degrees C ambient, you aren't going to be able to cool to comfortable temperature with one.

Tuesday, 28 June 2011

The difference between a fixed and a portable air conditioner

The process of refrigeration is very simple. A compressor sucks in refrigerant gas at low pressure, and then pumps it out into a section of pipe that ends in a restrictive nozzle, forcing it back into a liquid in the high pressure side, and forcing it back into a gas in the low pressure side. The properties of refrigerant are such that it absorbs heat while at low pressure and gives off heat at high pressure - effecively removing the heat energy from one point and depositing it in another.

This is simple to imagine in a fixed air conditioner, the compressor sits outside and the high pressure part runs throughout the outdoor unit, and the low pressure pipework connects the compressor to the indoor unit. If they are run in heat mode a reversing valve means the compressor runs in the same direction, but the refrigerant is pumped the opposite way around the circuit.

In a monobloc portable air conditioner, it works essentially in the same way. Except the outdoor and indoor unit are contianed within one box. Half of the box is the indoor and half is the outdoor. The pipe circuit is more or less the same, except it is contained within a smaller area - each half has an air intake, so the unit has two grills which are sucking air in, and each half has an outlet - the indoor outlet which simply recirculates into the room, and the outdoor outlet which pushes air down a duct to the outdoors.
The downside of this is that it creates a slight negative pressure in the room where the machine is operating, therefore pulling warm air through doors, vent holes and any gaps which are not air tight.

A more efficient option is the water cooled split portable air conditioner which uses water transfer the heat much like a fixed installation. This therefore recirculates 100% of the air which passes through the indoor unit and does not create the negative pressure, giving more efficiency.

Wednesday, 22 June 2011

Water Cooled Split Portable Air Conditioner or Monobloc Portable Air Conditioner?

The normal standard configuration for a portable air conditioner is a monobloc.  These are a single box, with two air intakes, and two outlets, one outlet for hot air and one for cool air.  Obviously the hot air should be ducted out of the room with flexible or fixed ducting.

The monobloc, or standard type uf unit such as the MCM230 Portable Air Conditioner, a modern, more powerful version of the MCM20 Portable Air Conditioner , the MCM280 Portable Air Conditioner a more powerful version still, or the 35,000 btu MCM350 Portable Air Conditioner the most powerful portable air conditioner which will run on a standard domestic 13A socket are all great machines.

Smaller domestic, plastic bodied portable air con units tend to only allow ducting of up to two or three metres. The MCM range allow ducting of 7 Metres making them much more flexible, they also have a large water collection tank, making emptying less frequent.

Sometimes you need to duct the hot air further still, it can be done with inline fans and similar, but a better solution is the water cooled split portable air conditioner. This unit is connected by a three pipe, one cable, umbilical to an outdoor unit.  The umbilical can be extended to 30 Metres and carries cold water in, hot water out, power for the outdoor unit and all condensate water.

In addition to the extra distance they can be located within a building, the smaller hole requirements for heat extraction (Ducting vs umbilical hose) and the lack of a requirement to empty the water tank - the water cooled split is more efficient.  Where a monobloc  sucks 100% air into the machine, 50% into the hot side and 50% into the cold side, it only pushes 50% back into the room, while 50% is shoved out the exhaust duct to get rid of the heat.  This negative pressure can cause the room to suck small amounts of warm air through any air holes or doorways or similar.  A water cooled split portable air conditioner however recirculates 100% of the air in the room, 100% goes in and 100% goes back into the room, maintaining a neutral air pressure and stopping the problem of warm air being drawn into the room.

The Water Cooled Split is also a quieter machine.

Portable Air Conditioner or Fixed Air Conditioner?

The first question to consider when looking for air conditioning, is whether to purchase a fixed air conditioner or a portable air conditioner.

For rented properties or offices, you must consult the landlord and get permission to have a fixed system fitted.  The fitting requires some destructive work and brings certain legislation and documentation into play which is ever increasing.  I won't list the rules and regulations here, as they are changing constantly and getting tighter and more rigorous as time goes by.  Even if you own the building the on-going cost of meeting current legislation is a valid concern.

If the landlord is happy to have it fitted then the next consideration is whether or not the cost is justified.  It is possible to move air conditioning systems, however it is expensive, it can cost more than the purchase of the equipment in extreme cases.

The advantages of fixed systems is that they tend to take up no floor space, whether you choose a ceiling cassette or a wall mount.  They can be quieter and more efficient.  With a portable air conditioner you can get some heat radiated back into the room from the exhaust pipe.  You may also have a tank which needs regular emptying as air conditioners pull water out of the air drying as well - this water has to be removed.  Some units have the facility to use a hose or similar to pipe the water directly out in the same way that a fixed unit does.

Another critical issue with fixed systems is the location of the outoor unit.  These can be a little unsightly and on the fronts of buildings, planning permission may be required, on a busy high street an outdoor unit on the front of the building is unlikely to be passed.  An alternative is a monobloc fixed air conditioner which uses an intake and exhaust vent and works in a similar way to a monobloc portable - these require no outdoor unit so may be a good choice where outdoor unit location is a problem.

A key advantage of portable air conditioners is flexibility, you can purchase one to use to cool workers in the office - then transfer it to the server room if one of the fixed units fails. You cam move premises without de-comissioning and re-comissioning the unit, and a new one can be purchased and swapped in if a critical unit fails.