Luba
MD
GL Collector – Technical manual
Version 1.0-EN-January 2012
© Enerconcept Technologies inc.
31
5.1 Recommended air flow
The Luba
GL collectors can operate with a unitary air flow varying between 1 and 12 CFM/ft
2
through the absorber. From an economic standpoint, the optimal air flow is 10 CFM/ft
2
of
collector.
There are situations when a greater temperature increase is desired, for example in drying
applications or in coupling with a heat pump. In these cases, an air flow of less than 5 cfm/ft
2
allows up to a 77°F (25°C) temperature rise above a mbient temperature.
In systems with great air volume and restrained physical space, Enerconcept recommends that
the Luba
TM
GL operate with a unitary air flow not exceeding 10cfm/ft
2
. Operating the system with
higher values, although technically possible, does not bring any tangible benefits: the small
amount of thermal efficiency gain is cancelled or cannot be compensated for by the additional
ventilation power required. In this case, it is recommended to leave the bypass damper partially
open even when it is very cold and sunny.
5.2 Efficiency curves of the Luba collector