Here’s an excerpt:

19,000 people fit into the new Barclays Center to see Jay-Z perform. This blog was viewed about 110,000 times in 2012. If it were a concert at the Barclays Center, it would take about 6 sold-out performances for that many people to see it.

Click here to see the complete report.

The Blog-Health-o-Meter™ reads Wow.

Crunchy numbers

About 3 million people visit the Taj Mahal every year. This blog was viewed about 37,000 times in 2010. If it were the Taj Mahal, it would take about 5 days for that many people to see it.

In 2010, there was 1 new post, growing the total archive of this blog to 24 posts.

The busiest day of the year was July 6th with 251 views. The most popular post that day was Simple Ways To Know If Your Fridge Is Low On Freon.

Where did they come from?

The top referring sites in 2010 were en.wordpress.com, search.conduit.com, search.aol.com, google.com, and dogpile.com.

Some visitors came searching, mostly for evaporator fan, refrigeration cycle, most reliable refrigerators, defrost timer, and refrigerator freon leak.

Attractions in 2010

These are the posts and pages that got the most views in 2010.

Simple Ways To Know If Your Fridge Is Low On Freon June 2008
14 comments

Most New Refrigerators Are Crap January 2008
23 comments

Filter-dryers and Capillary Tubes June 2008
11 comments

Evaporator Fan January 2008
4 comments

Defrost Timer June 2008
13 comments

Condenser Fan Motor

The photo above shows the condenser and fan of a fifteen-year-old Amana side-by-side that was probably never cleaned. It was replaced because it didn’t cool. A thorough cleaning of the condenser, fan motor, and fan blades restored it to proper operation. Don’t try to treat a new refrigerator this way; the fan motor and compressor might not survive the over-heating.

Although this fan still managed to rotate, sometimes the dirt and debris will jam the fan blades. Just make certain that you disconnect power before working on a condenser fan to prevent it from starting unexpectedly.

1. Loss of power

2. Bad bearings

3. Misalignment

Loss Of Power
This can be caused by a variety of conditions, but the result is the same: no current flows through the evaporator motor. The fan doesn’t work and the temperatures in the freezer and fresh-food sections of the refrigerator rise. The refrigerator will likely not cool to the set point of the cold control and the refrigerator will run continuously except when it is in a defrost cycle. This problem can be caused by loose wires, an open fan motor winding, or malfunctions in electronic controls. Troubleshooting evaporator fans was once much easier than today. Most ran when the compressor ran and received 120 VAC from the defrost timer when it was in the compressor run position. With the introduction of adaptive defrost and electronic controls monitoring inputs from thermistors, fans don’t always run just because the compressor has started.

Bad Bearings
Defective evaporator fan bearings can keep the fan from rotating even though the windings are good. One should ALWAYS disconnect the refrigerator from the power source before checking the fan to see if it is binding. The fan blades should turn freely if the bearings are good. If the blades are difficult or impossible to turn the bearings are defective. Many times when evaporator fan bearing begin to fail a high-pitched squealing noise is emitted (leaving no doubt that the bearings are failing).

Misalignment
Misaligned fans can’t rotate freely because the fan blades strike the evaporator cover. Sometimes the fan is jammed and can’t turn at all; sometimes it turns, producing a knocking or clicking noise. This problem is the result of the general quality decline in refrigerator manufacturing and seems to plague the cheaper models (read Haier), although I have seen this defect on units costing over a thousand dollars. The solution is turn off the power, remove the evaporator cover, and loosen the fasteners on the evaporator fan mounting bracket so YOU can align and tighten it properly. The other choice is to try to get the manufacturer to honor its warranty and that may be far more difficult than adjusting a fan bracket.

In units with a separate freezer and fresh-food compartment, the evaporator is normally in the freezer section and an evaporator fan circulates air to the freezer and fresh-food area through duct arrangements. The amount of cold air entering the fresh-food section is controlled by a manual or electronically controlled damper. The evaporator coil in these systems must have airflow from the evaporator fan to work properly and must be defrosted in order to maintain this airflow. Defrost is accomplished by energizing an electric heating element on or near the evaporator coil.

If the defrost circuit fails and ice builds up on the evaporator, airflow from the fan will diminish. Lack of airflow causes more ice to form. Soon the evaporator will be encased in a solid block of ice and no air will circulate. The result will be fresh food temperatures above 50 degrees and a freezer temperature at or near 32 degrees. The unit will run continuously since it cannot reach the set point of the cold control. This continuous running builds even more ice on the evaporator coil.

The way that the defrost cycle is initiated has changed over the years. When energy consumption was not a priority, a clock circuit energized the defrost heater based on time. A clock circuit would switch the unit into defrost every six, eight, or twelve hours (depending on which defrost timer the manufacturer installed) without any consideration of the usage or conditions. Even if the refrigerator was in a low humidity environment and had run very little, the heater still turned on every few hours. This system used a lot of energy.

After government regulations to improve energy efficiency were implemented in the late 1980s and early 1990s, the defrost circuit was redesigned so that a defrost cycle was based on compressor run time. A refrigerator not experiencing a lot of door openings and closings ran less often than one that was heavily used. Therefore some unnecessary defrosts were avoided (the ice build up depends on moisture laden air entering the unit) by initiating defrost based on accumulated compressor run time.

When the government dictated further reductions in energy consumption, manufacturers had to redesign the defrost controls to make them smarter in order to comply. The defrost system with its electric heater uses more energy than any other part of the refrigerator. Therefore it was the best place to look for energy reduction. The solution was adaptive defrost control. The defrost timer was replaced by an electronic control boards containing a microprocessor. Inputs to the control monitored door opening and closings, cumulative compressor run time, duration of last defrost, and in some models the ambient temperature where the unit was located. The algorithms programmed into the microprocessor would adapt the defrost frequency and duration to operating conditions and changes in usage. With adaptive defrost control, a defrost cycle can occur in as little as six hours or as long as seventy-two hours.

Adaptive defrost control does reduce energy consumption, but whether the energy savings is cost effective is another matter. Most do-it-yourself homeowners could troubleshot and repair a defrost system with a defrost timer, but many will call a repairman if electronic controls are not working. A price check on the net for a defrost timer resulted in prices ranging from 18 to 45 dollars. ADC boards seem to start at 65 dollars and most were closer to a hundred dollars. With a service charge and labor, having a technician replace the board will probably be a two to three hundred dollar repair. The money that the consumer saves on electricity will likely have to be spent repairing electronic controls.

Take a deep breath. Before you pick up the phone and call for assistance, look for the minor problems (that the repairman will still charge for). Open the fresh food compartment long enough to determine if the interior light comes on, proving that the kids or cat haven’t unplugged the unit. If there is no light, no noises, and no cool in the box, but the unit is connected by an undamaged cord to a receptacle, check the electrical panel to ensure that the circuit breakers or fuses for the circuit are not tripped or blown. If the breaker is tripped, unplug the refrigerator and see if the breaker will reset. If it trips, the problem is somewhere else in the circuit. In that case devise a way to try the refrigerator on a different circuit. If it starts normally, you need an electrician rather than an appliance repair person.

If the breaker resets with the refrigerator unplugged, there is likely a problem in the appliance. UNLESS the fridge is on an overloaded circuit. The average starting amperage on a compressor is 14 amps. If that load is connected to a 20 amp circuit that has other small appliances running when the refrigerator compressor tries to start, the circuit-breaker will trip (as it should).

Codes now require that a separate circuit be provided for the refrigerator, but that has not always been the case. Other odd external things that can cause a complete power loss to the refrigerator are defective circuits (loose and broken wires and connections) and a worn receptacle. Perhaps the prongs on the refrigerator cord have burned away from arcing in an old receptacle. Inspect them. Remove the bulb from the fresh food compartment and try it in a lamp to ensure that it isn’t defective. The combination of a bad bulb and a defective compressor starting-circuit or defrost timer may look like a complete power loss, but there is voltage present when the unit is connected to a live branch circuit.

In most cases, when a refrigerator stops cooling, the interior light works (and the fuses or circuit breaker and cord are good). Many will and should call for a professional repair person at that point, although I have done a few service calls where a toddler or small child had turned the cold control to the off position so check to ensure that the control is set to a number or letter.

Many refrigerators that have suddenly or gradually stopped cooling will be making noise ( as in fans and/or compressor running). Refrigerators with good running compressors and a full charge of freon will not cool properly if the condenser is dirty, the automatic defrost system is defective, or if the condenser or evaporator fans are not working. The unit will not cool at all if the compressor or the compressor-start circuit is bad.

If everything I wrote in the last paragraph is a complete mystery, it may be time to call an appliance repair service.

Fig 1 Refrigerator with freezer section on top

Take the refrigeration components, controls, and ancillary devices such as ice-makers, fans, lights, and water valves out of a refrigerator and one is left with a plastic lined compartment surrounded by insulation and and a pretty outer covering of thin sheet-metal (okay, very thin sheet-metal on most new refrigerators). An insulated box with the least amount of insulation that the market will accept. That amount seems to be about two inches these days which works out to about R10. Put your hand on the side of a refrigerator when it is running and feel the cold. Then try to guess who is paying for that cold. If you try this on a freezer or dorm fridge with the condenser beneath the sheet-metal skin, you feel heat rather than cold.

The person that decided to make an R-10 insulated box and put the condenser just outside of the insulation (so that heat leaks back into the interior of the box through the inadequate insulation) was the same one that decided that putting a hot compressor under the refrigerator also made sense. Heat rises so while the compressor runs to make your box cold, it is adding to the heat-load that it must extract. I hear someone screaming my refrigerator is energy-star rated and is much more energy efficient than those old heavy (well built) energy-hogs of the past. I am saving the planet you mean man. Most of the reduction in energy usage has been the result of better insulation (not more of it) and the down-sizing of compressors, evaporators and condensers. Under-sizing systems to save energy may be why refrigerators now last eight years instead of twenty to fifty.

The modern refrigerators is a poorly designed appliance and none of the major manufacturers seem interested in rethinking the issue. One would believe that some of them were in the electric utility business.

Replacement filter-dryer

Filter-dryers are placed at the outlet of the condenser in household refrigerators and contain mesh screens to trap contaminants and chemicals to absorb moisture. This provides protection to the capillary tube which can become clogged and block the flow of liquid refrigerant to the evaporator. A completely blocked capillary tube will stop all refrigerant from reaching the evaporator and no cooling takes place.

A clogged capillary tube is difficult to diagnose since it seems the unit is low on refrigerant (the evaporator doesn’t receive refrigerant, but not because it has leaked out). This is one situation where piercing-valves and manifold gauges are necessary to be certain. A system with a clogged cap tube and a good compressor will pull the low-side suction pressure down into a vacuum as low as 20 inches of hg. The condenser will be cold since it contains liquid refrigerant under high pressure. If the high-side pressure is low and the low-side is in a vacuum, the problem is likely a lack of refrigerant rather than a clogged capillary tube.

The filter-dryers installed to protect the capillary tube can also clog and the symptoms look the same as a clogged capillary tube. If a filter-dryer is only partially clogged and creates a pressure drop it will be coated with frost. A frosted dryer or frost on the cap tube at the outlet of the dryer indicates a partially clogged dryer that needs to be replaced. Dryers are cheap, but the economics of hiring a refrigeration tech to recover the refrigerant, replace the dryer, and then evacuate and recharge the system will depend on the age and cost of the system and type of refrigerant. R12 systems are likely better retired.

Capillary tubes usually clog in the first few inches after the dryer unless the system is contaminated with moisture. Moisture will almost always freeze and form an ice-plug at the inlet to the evaporator. This happens if the system is opened, moist air allowed to enter the piping, and a complete evacuation with a quality vacuum-pump is not performed prior to recharging.

Cap tubes can be replaced, but it is not an easy task. Almost all are attached to the suction line for much of their length. Their internal bore and length are part of the refrigerator design and cannot be replaced with just any cap tube one might have. The size depends on the type of refrigerant and capacity of the compressor.

In my foolish youth, I used to replace clogged cap tubes on almost new refrigerators by removing the evaporator, suction line, and cap tube back to the compressor area (as long as they were not buried in the foam insulation) and replacing the whole thing with a similar evaporator/suction line/ cap tube assembly from a scrapped refrigerator. The refrigerator that I am using now received this treatment, a new compressor, and a charge of R-409a over eight years ago.

In the past year I have seen three Frigidaire side-by-side refrigerators in which the capillary tube had not been brazed into the filter-dryer during manufacture. Thus they were sold (and returned to the retailer) without refrigerant. The replacement of the filter-dryer, evacuation, and charging with R-134a was worth it since they retailed for almost two thousand dollars each. Two other new Frigidaire units that I saw had broken cap tubes where they entered the filter-dryer. This likely happened in shipment (its a long way to China) due to the crappy placement of filter-dryers on Frigidaire side-by-sides.