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Small Systems 20 bar

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tips & tricks


"Tips and Tricks"

Lush blooming orchids, exuberantly growing exotic plants, healthy reptiles and merry twittering birds are not really results of magic, rather a consequence of fitting humidity. To design a small fogging plant and run it accordingly to the needs of plants and animals also is no magic.

The recipe: take a pinch of physics, a little bit of technical knowledge, a quantum of knowledge about plants and animals and stir it with a "green thumb".
Shortly afterwards visitors will become fans and will admire your results ...

Layout of a small Fogging Plant
Less is often More ...
Which way to point the Nozzles ?

Throw of Fogging Nozzles
Sensors - Yes or No ?
"Wonder Remedy" Hydrogen-Peroxyde
Lifetime of Pumps
Static or dynamic Fogging?

Layout of a small Fogging Plant

Since we have presented our 20-bar Small Fogging Plants during Spring of 2003 we have delivered some 1.500 devices for a wide variety of applications worldwide ... and have therefore collected quite some experience.

If you are not really sure how to configure your desired humidification equipment to get the best result at the lowest investment let us help you. We like do that at no cost via mail-inquiries, personally by telephone or even by a visit to your home if it can be reached by us easily. Pose yourself the following questions :

  • What is the main objective of your humidification equipment ? (Humidification, Cooling, Watering, ...)
  • What space is to be humidified / climatized ?
    - Glass Case
    - Terrarium or Paludarium with dimensions length x width x height
    - Porch, glassed-in balcony, wintergarden ,... or
    - Glasshouse with dimensions (volume)
  • Humidification plants are configured according to the volume (m³),NOT the floor space (m²) !
  • Alternative application with info about the desired objective
  • What should be humidified / climatized ?
    - Plants ... which ones ? e.g. Orchids, Nepenthes ...
    - Animals ... which ones ? e.g. Reptiles, Birds, ...
    - Technical- or Organic Products, Foodstuff, ...
    - Other ....
  • Where should the equipment be installed ?
    Town, Province (if any climate estimations should be made - we are in possession of extensive tables with climate data)
  • Which type of water is to be used ?
    - e.g. Osmosis-Water, Rainwater, Wellwater
  • If you are using tap- or well-water, what hardness does the water have ?
    If you do not know this, tell us where it comes from - we will try to research the water properties,
    e.g. at communal offices or water works.
  • Which temperature- and humidity parameters are desired ?
  • Do you have additional wishes like morning dew, integrated clock, dry-run protection for the pump or do you want to use an own, existing control device ?
  • Do you need information about running-times, fogging times, parameter settings by us or by other customers which utilize similar application profiles ?
  • Any other questions ?
  • And then we are interested from where you have received knowledge about our systems - e.g. a society, a trade fair, by recommendation (by whom?), from the internet (which search engine, which search phrase?)

Less is often More ...

Often it is supposed that many very fine nozzles (e.g. K-100) will provide a better humidification than fewer, larger nozzles (e.g. K-200). In many case this is true ... but not under all circumstances.

The 20 bar feeding pressure of our small pressure pumps seem to be quite sufficient on the first glance, however the artificial fog turns really "natural" with a pressure of some 50 bar. So, our small pressure pumps are a compromise which provides the highest possible pressure at the lowest possible dimensions for enthusiasts keeping tropical plants or exotic animals.

The size of the fog droplets exhausted depends firstly upon the feeding pressure, i.e. that the exhaust angle of the fog stream reaches its maximum of some 90° with a feeding pressure of 50 bar. With this settings the resulting fog will be more voluminous, the droplets smaller and therefore the evaporation and cooling effect larger. At the same feeding pressure larger nozzles will provide a larger exhaust angle.

Just to tell the complete story: Fogging nozzles of other sources should not be called fogging nozzles, as they are rather spraying-nozzles which cannot provide hovering fog ....

According to the info so far fine nozzles (e.g. K-100) with an exhaust angle of 15° at 20 bar a more local humidification, pointing to one plant or a group of plants (ideal for orchidariums or terrariums), they are not the best solution for the uniform humidification of a larger volume like a glasshouse(even if you are using many of them) .

To illustrate that with a practical example: an Austrian customer ordered and installed a tropic-system with all needed hosing and 6 fogging nozzles K-100 for her 6 x 4 m orchid-house. About 6 months after installation she complained that humidification was too erratic - some plants were too dry while others were dripping with water. A visit showed that the distribution of the nozzles was too unequal, so that we recommended to use the large fan, which was already running in the orchid-house.

We installed a nozzle ring with 4 nozzles K-200 on the fan (instead of the former 6 nozzles K-100) and within a few minutes the orchid-house was filled uniformly with fog.

And the customer was enthusiastic about the fast success ...

(also refer to „Static or dynamic Fogging“)


Which way to point the Nozzles ?

Fogging nozzles should NEVER point downwards, they should be positioned horizontal, slanting upwards or directly upwards. The reason for this comes from physical processes, because cooled air (which is getting colder by means of the so called evaporation cooling) will always circulate downwards, because it is heavier than warmer air.

If the fogging direction in an enclosed space like a glass case or a terrarium would be downwards, a stream of cold air would be the result, where the fog would not really evaporate and create water puddle on the ground.

This would mean that the original motivation for fogging - adjusting the humidity would not be met, moreover too much water would be distributed.

When the fog is directed upwards, all droplets which have not yet evaporated have a longer way down to the ground which gives possibility to evaporate - so all water blown out has the possibility to evaporate and enhance humidity.


Throw of Fogging Nozzles

The throw length off fogging nozzles is primarily a function of feeding pressure. The higher the pressure the larger the throw. Our small systems work with some 20 bar which provides a throw of c. 1.20…1.50 m. Identical nozzles utilized in a high pressure system with 50 bar throw 3…3.5m).

When used in small volumes like small glass cases or terrariums this can pose some problems, as the fog stream my hit the opposite wall where the droplets can condense and run down into undesired places. This means that fogging nozzles and the feeding pumps may not be appropriate for very small volumes.

A trick can minimize this effect: if a ball valve is inserted into the feeder hose the pressure can be reduced manually, this will result is a reduced throw. This will increase the size of the water particles in the fog stream, however usually fine enough to provide evaporation.


Sensors - Yes or No ?

A starting remark: in nature there are no constant values, temperature and humidity are changing all the time. So think that plants as well as animals living in a terrarium love changes.

Glass houses, wintergardens and orchidariums usually are home to a high diversity of organisms and are there for the owner to enjoy them and not for production purposes in monocultures. Only with these humidity control with high precision make really sense.

A heretic remark: for the hobbyist there are cheap and expensive humidity sensors available, unfortunately no sensors which really fulfil accuracy and speed together.

The control boxes of our Plantfog systems are configurated in a way that the second-fine control abilities allow a humidity regime which is very near to natural circumstances. If you want to be informed about the current humidity in your cultivation area use a reasonably priced display instrument and optimize your humidity regime with the help of this device.


"Wonder Remedy" Hydrogen-Peroxide:

Whoever is lucky enough to be able to collect rainwater may come to the question how to keep the water fresh in its container if it has to be kept for a longer time. Hydrogen-Peroxyde can help if you put small doses from time to time into the water. More and much more pertinent information can be received from other cultivators who you can reach by means of internet-fores ...
(e.g. www.orchideenforum.de, forum.orchideenfreunde.eu,www.orchideen-wien.at)

If you can store the water in a cool and dark place the problem will remain small.


Lifetime of Pumps

The most important tip to keep the lifetime of your pump high - regardless whether it is a small or large pump - is the precaution that the pump should NEVER need to suck water, NEVER be exposed to large input pressure and NEVER RUN DRY.

If a pump need to suck water from a tank (it is positioned above the storage tank) there is always the danger that the input stream forms bubbles which can cause stalling which will result in running dry.

Pressure pumps do not like input pressures exceeding 1.5 bar. A higher pressure will put stress on gaskets which will lower the lifetime.

The definitive way to destroy a pump will be letting it run dry. While large and expensive high pressure pumps can be repaired in some cases, our small pumps will not survive such an event !

If these rules are obeyed our pumps look forward to a long life. The "oldest" tropic-pump has been installed in 2002 and is still running strong ...


Static or dynamic Fogging?

Static fogging means that only definitive areas or points in a cultivated area are to be treated with fog. The nozzles are mounted on hoses or tubes which are fastened permanently. The restricted capacity of our small fogging plants as well as the available investment prevent usually that larger volumes can be humidified to a higher degree.

Therefore we recommend to use static fogging mainly for restricted areas or volumes - for instance orchids, ferns or tillandsias are to be provided with humidity.

Dynamic fogging means to distribute the fog by means of an airstream provided by a fan. This system is able to humidify even large volumes very efficiently with rather small investments. This version can also utilize larger nozzles with a higher thruput (e.g. K-200 with 1.8 litres/hour @ 20 bar) because the airstream will dissipate the water particles. Usually a simple module "tropic-IP65" with 4 nozzles K-150 or k-200 will be sufficient to humidify glasshouses up to 30 m2 to 75% rH.

Important: the fan should run continuously to dissipate the humidity and circulate the air as well as for its own health as fans running continuously will stand humidity for a longer time

Small Systems 20 bar

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tips & tricks


last modified MAR 2013
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