Page 2026 - Foton Workshop Manual - Tunland (AT)

61-30 HEATER AND AIR CONDITIONING - REFRIGERANT

(a) When checking for major leakage at the connection of the cooling pipe, spray some
soap solution around the connection and look for bubbles if any. Though it is simple
and convenient, it couldn't detect minor leakage.
3 . Check for leakage with non-selective detector
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(a) It detects all kinds of liquid or gas leakages without taking account of the chemical
components of the tested substance. It is easy, stable and cost-effective. However, it
is not applicable to large areas.
4 . Check for leakage with halogen leak detector
(a) With specific sensors, it detects the compounds containing minor volume of F, Cl, Br
and I in the air, regardless the intervention of other substances. It is highly sensitive
and effectively minimizes detection errors. In case of large areas, the min. detection
threshold is 5g/year; and for spot detection, it is 1.5g/year (i.e., it can detect a leaking
point with the leakage volume of 1.5g a year).

5 . Check for leakage with dedicated electronic detector
(a) Complicated and expensive, it can sensitively detect a certain compound, regardless
the intervention of other substances. Take the dedicated detector of R-134a for
example. It is highly sensitive and selective, which can not only accurately detect the
leaking points, but also identify whether the refrigerant is R-134a. Due to its high
sensitivity, during operation, pay attention to the contamination in the surrounding, or
it may lead to detection error.
6 . Check for leakage with fluorescent dye
(a) Fluorescent dye generates fluorescence under UV, which is added into coolant or
refrigerant. In case of leakage, test the exterior of the system with a UV lamp and find
out the leaking point.

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