testing, noise, Loadest, building, energy, engineers, services, maintenance, air filters, insulation, acoustics, iaq. James Fricker
ABN 32 080 307 348
54 Felix Crescent
Ringwood North, Vic 3134
Mobile: 0414~804~097
Phone: 03~9879~5744
(Note: fax terminated as email preferred)
International +61

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Dear potential customer,
Please bookmark this or the main page and return weekly. For additional information, e-mail or phone me with your query.
If you would like to see my qualifications and employment experience (CV), please ask.
I look forward to working with you to solve your particular problems to increase your profits, James.

The following table will be updated regularly with information and tips regarding areas I consult in:

Air Conditioning Load Calculations 
Did you know - that a heavy-weight building does not automatically have reduced air-conditioning running costs? This is because running costs also depend on the occupancy. In general, if the building is only occasionally occupied (e.g. apartments), design for a lightweight building may reduce running costs as it can be more quickly cooled or heated as required. The exception is when the building is evaporatively cooled where the high air change rate makes it nearly equally effective for both heavy and light weight buildings. On the other hand, large diurnal ambient temperature swings may make heavy weight buildings more energy efficient. 
Building energy modeling can evaluate the $ of the alternatives.
Did you know - that air touching any surface cooler than its DEWPOINT temperature will condense to form water droplets? This condensation can cause corrosion, mildew, fungal growth, etc., if not properly considered. As a consequence, insulated walls and roofs need vapour barriers to prevent or minimise condensation. Note: a common error in Australia is that the vapour barrier is not always on the WARM side of insulation (at periods when condensation is likely). Fortunately, in most cases this is not a major problem due to Australia's mainly mild winters. But note that moisture condensed within mineral wool insulation (fibreglass, etc.) significantly reduces its thermal resistance which can further exacerbate condensation. 
Comfort ? Discomfort?
Did you know - that COMFORT is the nett perception of an individual as a result of his experience of all his sensations, i.e. air temperature, air movement, thermal radiation, noise, light, odour, and even allergic nasal irritation from air borne particles or chemicals, if present. 
Often this is over-looked and investigations of occupant complaints of "poor air-conditioning" ignore a key cause of his discomfort that led to his blanket opinion. Tip: Do not just investigate the fashionable cause, keep a Sherlock Holmes awareness during your investigation. Quite often a "stuffy" perception is caused by lack of air movement due to poor air diffusion or VAV control, even when there is adequate ventilation (outside air provision). 
Stuffiness is often simply the perception caused by over-heating. 
High or Medium Air Filtration?
Survey Question! - (1) Many have argued that the human body has evolved to cope with air pollution to a considerable extent. Our noses filter large particles and our lungs have mucus rejection mechanisms to eliminate inhaled and captured particles, so air conditioning filters need only be adequate to protect equipment, e.g. maintain the heat transfer efficiency of cooling coils. 
(2) Others argue that circulation fans of air conditioning systems keep sub-micron particles continually air borne as these have relatively high surface area per volume and thus have settling times of many hours, and as these particles are respirable, they should be filtered out. 
Advocates of (1) then say that (2) is too expensive as both filters and fan energy costs are both much higher with F7 filters, and where is the evidence of improved health of occupants to justify such extravagance in these times where energy conservation is imperative? 

Your opinion is needed! Pls e-mail me with your opinion, with or without supportive argument and data. The results of the survey will be published here and on the AIRAH web site. 

Residential Air Duct Cleaning - Is it Necessary?
The New Growth Industry - cleaning residential air ducts? Is it necessary? 
In Melbourne, rarely an hour passes without someone radio advertising duct cleaning services for home heating systems. How did this new industry eventuate? Is it necessary? 
Some leading duct manufacturers argue that flexible air ducts are not robust enough to withstand most methods of cleaning. They argue that cleaning often damages ducts and they then need replacement, and this is used by some duct cleaners to extract extra profit from the unsuspecting home owner trying to protect the health of his family. One duct supplier even considered this an unethical practice and stated home owners should save the cleaning cost and just replace dirty ducts. 
But why do ducts need cleaning in the first place? Answer: lack of adequate return air filtration. Ensure your heating system has an adequate return air filter, (i.e. large enough and of suitable quality to do its job) but do not install one with pressure drop that excessively reduces air flow and increases fire risk. Regularly replace the filter when its pressure drop becomes excessive. For further advice, contact me.
Building Shadow Analysis 
Did you know - that calculations for building shadows are like those for sundials? Shadow positions and angles are determined by latitude (e.g. Melbourne has longer summer days than Brisbane), day of the year, the earth's axis slope, the time zone, whether day-light saving is active, and shape and orientation of the surfaces producing shadows. A convenient tool for assisting with shadow analysis is a Heliodon which is a specially designed machine which orients lighting on to a scale model. James M Fricker Pty Ltd design and make these to suit your needs.
Seasonal Variations 
Did you know - that besides the earth's axis slope (23.45°) the seasonal ambient temperature and solar energy variations are affected by other factors? For example, on July 4 the sun is 154,400,000 km away but on January 3 the sun is only 144,600,000 km away, and as solar intensity varies as the square of distance, summers in the southern hemisphere have a tendency to be more severe than in the northern hemisphere. (An extra reason to slip-slap-slop the SPF15+!)
Solar Power
Did you know - that just beyond the earth's atmosphere, the average solar radiation is 1370 W/m², and ultraviolet radiation comprises 7% of the total energy, the visible 39%, and the near infrared 52%. But at the earth's surface, absorption by the ozone layer, scattering and other effects lead to an energy distribution of approximately 3% in the ultraviolet, 38% in the visible, and 59% in the infrared, for latitudes near Melbourne's. Your skin is a very effective absorber (and radiator) of the infrared, affecting your comfort in air conditioned rooms as well as on the beach. Solar energy convertors are also designed to efficiently absorb the infrared as this is the dominant component of solar energy.
Reflective Insulation
Do you know - how thermoflasks work? Heat can be transferred by conduction, convection and by radiation. The vacuum in a thermoflask stops conduction and convection, and the highly reflective surface minimises radiation heat transfer. 
The same principles can also be applied to insulating building components. If surfaces are parallel and suitably oriented to control convection, the reflective cavity can be a very cost effective insulation system. James is one of the very few who specialises in evaluation of reflective insulation systems using software he developed.
Acoustics & Insulation
Did you know - that flexible acoustic air-conditioning ducts may have numerous tiny holes specially for noise attenuation of the difficult-to-kill low frequencies? 
However sharp bends in flexible ducts may cause very high pressure drops that will cause air to percolate between the inner liner and outer sleeve, severely compromising the insulation rating.
Air Filtration
Did you know - that despite what many claim, most normal air-conditioning filters in office buildings do not legally require a minimum sub-micron efficiency of 20%? 
Did you know - that most office air filters do not stop the respirable small particles that pass through most commercial vacuum cleaners. These same particles are so small they would take hours to settle but they don't as they are kept air-borne by the fan system. 
Specification preparation, evaluation, and selection of suitable filters can be done independent of a filter supplier. 
For further information, please ask. (James who was the NATA filter testing laboratory manager at Enersonics Pty Ltd for over 10 years.)
I maintain an interest in education and still enjoy teaching (see my CV). As a consequence last year I taught Hydronics, and this year I am teaching Noise Control at RMIT. I am using the excellent AIRAH publication "Noise Control" but I invite your contribution to a new web link page for acoustic studies. 
Several people have requested more detail on the LOADEST software I developed for Emailair, so here it is: 

What is LOADEST?

LOADEST is a Single Zone Load Estimation program especially suited to typical Australian light-weight commercial building construction. 
It estimates building air-conditioning load using CSIRO methods and Australian weather data. 

LOADEST receives input of building elements, orientation, latitude, climate, and design criteria, then calculates heating and cooling loads for air-conditioning the building. 

How Does "LOADEST" Work?

LOADEST air-conditioning calculations are based upon research by CSIRO and Solar & HVAC Software Services. 
Loadest uses an internal database PROJINT.MDB containing weather and surface materials data. 
The PROJECT.MDB database file stores all user's data. It does not store results which are only available immediately after selecting "Calculation". 

The sequence of calculations is: 

For each glass area, the Solar Gain (SG) for clear glass is calculated from the inputs of orientation, latitude, clearness number, month and hour of interest, and external Shading Factor. This is multiplied by Delay Factor, glass Shading Coefficient (SC), Internal Shading coefficient (IS), and glazed area (SQM) to determine solar load and displayed as Solar Watts. 

The design cooling and heating temperature differences, glass transmission modifiers, and glazing area, are used to determine the glazing cooling and heating conduction loads. 

Similarly the conduction cooling and heating loads are calculated for walls, floors and ceilings. These are calculated using Heating and Cooling Factors (CF & HF) which are surface conductances (W/m².K) weighted by thermal storage and other considerations. Conduction heat loads use temperature difference between ambient air and room temperature and so wall and roof Cooling Factors include an allowance for typical solair temperature for sunlit surfaces. Factors supplied were researched by CSIRO, Enersonics Pty Ltd, or by James M Fricker Pty Ltd. 

Sensible (and, if applicable, latent) allowances are then calculated for Lighting, Special Heat Sources, People, Duct Gains, and Infiltration and Ventilation. 

LOADEST calculation causes display of the month and hour of maximum total solar load for both morning and afternoon for the period September to March inclusive. The user can select either of the suggestions, or enter another month and hour and recalculate. ("Hour" used is the apparent solar time.) 

Lighting and other internal heat sources are assumed to be absent while the building is warming up in winter, and so are omitted from the estimate for heating load. 

I have heard of its excellent reputation and popularity, but what is so special about LOADEST?

LOADEST has been carefully ergonomically designed to enable the fastest entry of required data for a reasonably accurate load estimation. It also has a reputation for its speed of calculation and nice, single-page, presentation of results. LOADEST also stores all data of every project in a database for easy recall, copy, edit, or reprint. It is distributed on a single 3.5" floppy disk. Click here to find where to get it. 

What users say: 

"Fax from Bruce Milner,



 If you would like me to develop Load Estimation, Equipment Selection (or other software) specifically for your needs, 
give me a ring or an e-mail to discuss further.
Low Energy Housing
Are you aware of the controversy over Reflective Insulation vs Bulk Insulation? This section will be updated soon. Stay tuned!
Diffusers and Air Flow
Question:  - What are the ideal properties of a diffuser for 
  •  Evaporative Cooling? Answer: Because the temperature difference between supply air and room air is low, a large volume of air is required to meet the load. Also, as this diffuser is nearly always only for cooling, increased cooling effect can be obtained by designing for relatively high air velocities at occupant level, hence diffusers specifically for evaporative cooling have high throw, relatively little resistance and significantly project air downward and outward. 
  • Cooling by air conditioning? Answer: Here there is higher delta t and reduced duct sizing for economy, hence these diffusers have higher resistance to project air further for less air flow. To prevent "dumping" of chilled air, diffusers in office buildings typically should project air close to the ceiling.
  • Heating? Answer: Because warm air is bouyant air, it tends to cling to the ceiling leaving occupants below cool. Also, because furnaces can heat much more than coolers can cool, the delta t is much higher hence for heating the air flow rate can be less, but this reduces throw; thus diffusers for warm air need more careful design to prevent drafts and stratification. 

  • Good entrainment (good mixing) is essential to maximise the efficacy of all diffusers, especially for diffusers that handle both cooled and heated air. 
    A common cause of comfort complaints in variable air volume (VAV) systems is poor selection of diffusers. 
    Many times I have helped improve the design of air diffusers; do yours need improvement?
    If you enjoyed this page or have any suggestions or additions, send me an e-mail.
    I look forward to hearing of your particular interests.
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     Please ring, fax or e-mail me to discuss your needs.
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