{"id":1978,"date":"2010-12-07T08:18:15","date_gmt":"2010-12-07T12:18:15","guid":{"rendered":"http:\/\/www.engineeringradio.us\/blog\/?p=3928"},"modified":"2023-09-23T09:21:38","modified_gmt":"2023-09-23T13:21:38","slug":"i-got-the-air-conditioner-blues","status":"publish","type":"post","link":"https:\/\/www.engineeringradio.us\/blog\/2010\/12\/i-got-the-air-conditioner-blues\/","title":{"rendered":"I Got The Air Conditioner Blues"},"content":{"rendered":"\n

Back in the day, when tube transmitters ruled the broadcast world, the common practice was to have a big cooling fan moving outside air through the transmitter building connected to a thermostat. \u00a0Temperature swings of 30 to 40 degrees were common, however, the tube rigs could handle almost any temperature that didn’t melt plastic or freeze water.<\/p>\n\n\n\n

Today’s solid-state transmitters are not that rugged. \u00a0They like to have their rooms around 70 degrees +\/- 10 degrees or so. \u00a0Not to mention the other computer-controlled equipment commonly found at a transmitter site. \u00a0Things like air chain processors, STLs, remote controls, etc. \u00a0So, lots of air conditioning is the norm, and with lots of air conditioning comes lots of maintenance.<\/p>\n\n\n\n

Air handler air filters need to be checked and replaced often. \u00a0Condenser coils seem to attract every type of flying debris on the planet and need to be cleaned once, possibly twice per year depending on tree and weed species near the site. \u00a0Even with preventative maintenance, occasionally things like this happen:<\/p>\n\n\n\n

\"AC<\/a>
AC condenser frozen dryer and piping<\/figcaption><\/figure>\n\n\n\n

Of course, the entire cooling coil inside is frozen solid.<\/p>\n\n\n\n

This condenser is low on refrigerant, causing icing problems. \u00a0It has a slow leak somewhere and is about to be replaced. \u00a0Other reasons for this happening are malfunctioning or non-existent low ambient kit on the condenser fan. \u00a0Sometimes less than knowledgeable persons will install a 5-ton unit designed to run throughout the year but not take into account the effect of moving below-freezing air at high speed across the coils. \u00a0Insufficient air moving across the cooling coil will also cause this. \u00a0Insufficient airflow can be due to plugged air filters or clogged fan\/blower blades.<\/p>\n\n\n\n

This one is even better (same condenser unit):<\/p>\n\n\n\n

\"AC<\/a>
AC condenser broken fan<\/figcaption><\/figure>\n\n\n\n

The fan blade is sheared off and jammed into the condenser coil. \u00a0This happened during power transfer from generator power to commercial power. \u00a0Naturally, it was at 1 a.m. in the morning after a pole-mounted transformer had been replaced. \u00a0When the building transferred back to commercial power, I went outside to use the “bathroom” before my two-hour drive back home. \u00a0I thought I smelled something hot, you know that cooked paint\/plastic smell, but couldn’t really track it down… the winds were kicking up and another thunderstorm was on the way.<\/p>\n\n\n\n

The next afternoon, however, when the sun was up and the site was working on one air conditioner, the temperature alarm went off. \u00a0Upon arrival, I found the condenser breaker tripped, resetting it caused the building lights to dim. \u00a0The fan motor was shorted to the case. \u00a0I would theorize the aluminum fan blade suffered from metal fatigue, likely because the blades were not balanced causing a vibration. \u00a0When the power transfer occurred, there was just the right combination of torque and centripetal force to cause the blade to rip, and then lodge in the condenser coil.<\/p>\n\n\n\n

The fan motor has been replaced, but I think it is time to replace the whole condenser unit, which will be expensive.<\/p>\n\n\n\n

\"AC&R<\/a>
AC&R Gauge set<\/figcaption><\/figure>\n\n\n\n

I found having a set of gauges to check the head pressure and suction is a good diagnostic tool to quickly pinpoint problems with HVAC units.  This way, when the HVAC tech shows up, you can quickly point him in the right direction.<\/p>\n","protected":false},"excerpt":{"rendered":"

Back in the day, when tube transmitters ruled the broadcast world, the common practice was to have a big cooling fan moving outside air through the transmitter building connected to a thermostat. \u00a0Temperature swings of 30 to 40 degrees were common, however, the tube rigs could handle almost any temperature that didn’t melt plastic or … Continue reading I Got The Air Conditioner Blues<\/span><\/a><\/p>\n","protected":false},"author":4,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[17,21],"tags":[160],"class_list":["post-1978","post","type-post","status-publish","format-standard","hentry","category-maintenance","category-tales-of-disaster","tag-hvac"],"_links":{"self":[{"href":"https:\/\/www.engineeringradio.us\/blog\/wp-json\/wp\/v2\/posts\/1978","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.engineeringradio.us\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.engineeringradio.us\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.engineeringradio.us\/blog\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/www.engineeringradio.us\/blog\/wp-json\/wp\/v2\/comments?post=1978"}],"version-history":[{"count":7,"href":"https:\/\/www.engineeringradio.us\/blog\/wp-json\/wp\/v2\/posts\/1978\/revisions"}],"predecessor-version":[{"id":12445,"href":"https:\/\/www.engineeringradio.us\/blog\/wp-json\/wp\/v2\/posts\/1978\/revisions\/12445"}],"wp:attachment":[{"href":"https:\/\/www.engineeringradio.us\/blog\/wp-json\/wp\/v2\/media?parent=1978"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.engineeringradio.us\/blog\/wp-json\/wp\/v2\/categories?post=1978"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.engineeringradio.us\/blog\/wp-json\/wp\/v2\/tags?post=1978"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}