Antihistamines, H1. Histamine antagonists or antihistamines are drugs that relieve allergy symptoms.Histamine is a chemical used to identify and remove substances that trigger an allergic response. Ã¢ There are four histamine receptors &#40;designated H<sub>1</sub>, H<sub>2</sub>, H<sub>3</sub>, H<sub>4</sub>&#41;.
Water leaks in central air conditioners are almost always caused by a problem with the condensate pan or drain pipes. The most common of those problems is a clogged drain line. When your condensate drain line gets clogged, water backs up and builds up in your pan. With nowhere to go, that water will begin to leak over your drain pan and onto your system and your floor. Another problem that can lead to a water leak is a crack somewhere in the pan or in the drain pipes.
If the filter appears dirty, replace it immediately. A dirty filter will cause ice to form on the unit's evaporator coils, and when that ice melts, it drips water. The third reasonâa stopped-up condensate lineâis the most common cause of A/C leaks. The condensate line drains condensation from the overflow pan to the outside or directly into a drainpipe. When the line is clogged, water backs up and floods the overflow pan.