توضيح لردك على موضوعي
وان العازل اللي اخترته غير معروف
اتوقع ان معرفة نوعية العازل المستخدم لدى اغلب المحلات هو فعليا غير معروف لان شركات العازل الحراري المنتجة تنعد على الاصابع و اما المحلات عدد شعر الراس و الكل يدعي انها الماركة الخاصة فيه لكن الواقع مختلف تماما و يوهمك بجودة عزل الاشعة الحمراء عبر جهاز بدائي لتنقنع ان نسبة العزل 99% :a1120(121):
نسب العزل تقاس من قبل مهندسين مختصين و وفقط الشركات الكبيرة اللي تعتمد معايير موحدة اما الصغيرة ممكن تتلاعب
عزل الاشعة الحمراء غير مهم ( ارجو مراجعة ردي في موضوعك )
بالعكس العازل من شركة لومار و هي من اكبر المصنعين للعازل الحراري
ابحث عن سوليتا وهي المالكة لشركة لومار و في كول و ماديكو
العازل اصلي 100%%%% و من 2011 الى الان معاي زي الحلاوة ما شاء الله فاللي اشتريه اعرف ما هو وليس مجرد فيلم حراري ولو هو كذلك لكان الفيلم تشقق من بعد كم شهر
لا ليس الافضل ما دام التوفير يصل 1500 ريال واللي يكفيني شراء التظليل على اقل تقدير مرتين لو احتجت فعلا للضمان
اذا تشوف ان الضمان يسوى 1500 ولا حتى 1000 ريال فهذا الشي راجع لك لكن بالنسبة لي ما اشوف الضمان يستاهل هذا المبلغ واذا خرب علي شي مستحيل راح يخرب كله بالكثير شباك او اثنين و اصلاحه لدى الوكالة ما راح يكلف مبلغ كثير 200-300 ريال لان الاستبدال يكون رخيص عند الوكالة
وهذا رد من الوكيل لومار فلوريد بامريكا لاني سبق و ان سالت عن نسبة عزل الاشعة الحمراء واهميتها و بعدها تاكدت ان الموضوع فعلا دعاية و تسويق وهمي خاصة اجهزة القياس اللي بالمحلات
IR Rejection Claims -What Do They Mean?
Two of the most marketed films today are Infra-Red absorbing dye films (sometimes referred too as simply ‘IR Films’)
and ceramic window films. Most IR absorbing dye films use “organic” dye that absorbs “near-infrared” radiation at
specific wavelengths. It is not uncommon to see advertisements that will claim 93, 97, and even 99% IR rejection!
It seems like impressive figures that will translate into huge heat rejection performance. Not surprisingly, consumers
with the help of an uneducated salesperson can be led to believe that 99% IR rejection is in fact 99% heat rejection.
Can a Window Film Reject 99% of the Heat?
Well as much as we would wish that a window film could reject 99% of the heat, in reality there is no solar control
window film that can do that. Therefore the question, what does the 99% IR rejection claim actually mean? To answer
this question we first have to look at what contributes to thermal energy.
Solar Energy
distribution Chart
Fig 1.1 The Infrared Spectrum 780-2500nm only accounts for about half of the total solar spectrum.
The pie chart in Fig 1.1 shows the 3 regions that make up heat or the total amount of solar energy. Note that Infrared
only contributes about half of the energy and the other half comes from the Visible Light and Ultra Violet regions of the
solar spectrum.
Assuming we were to filter out 99% of the infrared radiation between 780-2500nm, we would only be able to to reject
about 49% of the total solar energy. That is far from 99% heat rejection!
To make matters more confusing, not every window film manufacture measures their product’s infra-red rejection the
same way. The “near-infrared spectrum” (NIR) stretched from 780-2500nm and accounts for 48.93% of the total solar
energy. Very few window film manufactures average out the IR rejection across the entire NIR spectrum.What is most
common is for a manufacture to sample specific wavelengths while omitting the majority of the NIR spectrum. Notice how
this is illustrated in Fig 2.2 where the area between 900-1000nm is highlighted in blue. This particular manufacture
measured their film’s ability to reject infrared in this very narrow region only and then they market that their film rejects
97% of the infra-red. So why don’t they measure the entire range between 780-2500nm? Well, if you were to average
this figure out over the entire NIR spectrum then it would be only about 86-87% infrared rejection, far lower than 97%
and far less marketable.
This is just one example of the confusion that is created in the marketplace. New automotive IR rejecting films have hit
the US market with claims of very IR rejection. When investigated closely you will find that these companies employ the
same marketing tactic of implied high heat rejection by using infrared rejection sampled from two or three narrow and
low intensity regions in the NIR spectrum. The key to understanding how these films really perform is knowing what
IR rejection is, and what it is not.
Fig 2.2 Some window film manufactures only measure a fraction of the near-infrared spectrum usually in a low intensity region as noted in the blue highlighted area between 900-100nm.
What Is Infrared Rejection
Basically, IR rejection is a measurement that is only used in marketing. It is a regional measurement that is not indicative
of a film’s total performance. In fact, IR rejection is never used in determining energy efficiency or lack thereof. It is not
used by noteworthy institutions such as the Department of Energy, the National Fenestration Ratings Council (NFRC),
ASHRAE, nor is it used in any building modeling software designed to calculate energy usage. Why? Simply, you cannot
determine total energy rejection or transmission with just the IR rejection measurement.
There are however some measurements that will tell you a film’s overall energy rejection and transmission. First is a
measurement called the “solar heat gain coefficient” or better known as the “SHGC.” The SHGC tells you how much
energy is being allowed to transmit through the glazing with film applied. So if your window film has an SHGC of .30
then it means that 30% of the total solar energy is transmitting through the film into the interior. The opposite of this
would be the total performance measurement known as the “Total Solar Energy Rejected” or “TSER.” TSER is the
opposite of the SHGC, so then your .30 SHGC equates to 70% Total Solar Energy “Rejected” by the window film.
Abdullah, We hope this helps. As you see, IR has nothing to do with the Heat Rejection performance of the film. LLumar
doesn't even try to market their film with mentioning anything about IR, because their performance and TSER is much more
important. We also wanted to let you know that our parent company has been in business for over 25 years and we can
assure you that unlike many other do-it-yourself companies in our industry, we always provide our valued customers with
exactly the finest products that we advertise and all of our brands including the LLumar Film that we carry ... are genuine!
Also, you are never annoying and we are always here for you to answer any question that you may have and to serve
