Celebrating A Legacy

Dad turned 89 today. In celebration, my sister hosted a party at Stanfield Air Systems so the many folks who have come to know Dad over the years could celebrate with him. Friends from all walks turned out. The room was crowded with people regaling each other with stories about their life and work with Dad.  Family, neighbors, employees, customers, and competitors all turned out to celebrate and wish him continued good fortune. Dad started Stanfield Air Systems in 1968. The company he started grew in reputation as the place to go, especially if what you wanted to do was a bit off the beaten path. Dad was among the first in our area to tackle high velocity systems, solar heating, and ground source heat pumps. Along the way he also installed Arkla-Servel gas fired air conditioners and Amana EG mini-boiler systems. How did he know about all these technologies? He read and studied. Studying your field was just part of your job. And if I am completely honest here, I think he really enjoyed doing different things. If you work hard at your craft and treat people fairly you collect a lot of friends. Today showed there are many folks in Athens who are very glad Lynn Stanfield moved here and started Stanfield Air Systems in 1968. Happy birthday Dad!

Condensing Furnace Drains

With the abundance of condensing furnaces, drain problems are no longer limited to the summer months, but are now a year round concern. Although the drain on a condensing furnace is a relatively small detail in the overall scheme of things it can shut a system down if not run properly. Normally, there are two furnace drains: one for the condensing heat exchanger and one for the vent. Some furnaces combine then inside the furnace while others require the installer to take care of that. The vent should slope towards the furnace so any water condensing inside the vent runs back to the drain. This also prevents water dripping out the vent and creating an ice dam. The drains need to be trapped, but only once. After the drain leaves the trap the pipe should never rise. Sometimes sags in PVC drain lines cause unintended secondary traps. Secondary traps will keep the water from draining out, creating a mess. Many manufacturers now provide a manufactured trap. If a furnace has a built in manufactured trap you should not add another one. Multi-poise condensing furnaces pose a special problem: you have to know which end is up (literally) to know how to position the trap and drain. Often these furnaces come configured for upflow installation but must be reconfigured for downflow or horizontal installation. Make sure the drain gets moved to the right location for whatever position the furnace is installed in.  In general, you should not run the air conditioning condensate drain and the furnace condensate drain into a common line. The positive pressure from the coil can travel through the drain to the furnace drain and cause the vent safety switch to trip. It is OK to run both into the same condensate pump basin, so long as it is open to the air and not sealed tight. If you use a condensate pump, make sure that it is rated for furnace duty. The condensate from furnaces is moderately acidic and can eat up some pumps that are not designed to handle furnace condensate. If the drain will run through unconditioned space that may drop below freezing, it will need to be wrapped with a heat tape to prevent it from freezing. If the furnace is located in an area which can be damaged by water overflow, such as an attic, it will require a secondary drain pan underneath the furnace. Finally, remember water runs down hill. The drain should slope away from the furnace until its outlet.

Perfect Weather for Defrost Problems

WE are experiencing  lot of cold, rainy days here in Georgia. The temperatures hover just above freezing into the mid 40's. This type of weather is perfect weather for heat pump defrost problems. Heat pumps have to defrost more in weather just above freezing than in much colder weather. If the temperature is so cold that water freezes out of the air, there won’t be much water in the air. If there is not a lot of water in the air, heat pump will not develop very much frost. On the other hand, if the temperature is 40 degrees and raining, there is a lot of water available. The coil in the heat pump will be below freezing even when it is 40 degrees outside, so the water will form frost on the coil. The system is more likely to need frequent defrosting at temperatures just above freezing than at much colder temperatures.  This is not to say heat pumps won’t got into a defrost cycle at very cold temperatures, but there is much less ice to defrost. The first thing to check on an iced over heat pump would be to make sure the outdoor fan motor is operating. If the outdoor fan motor is not moving air across the coil, it will frost very quickly in cold, wet conditions. The normal defrost periods would not be able to keep the coil clear. An undercharge can also make a system freeze up faster and keep it from clearing the ice when it does go into defrost. If water created when the coil is defrosted cannot drain away from the unit, a large ice floe can build up underneath the unit. This can create an ice chunk around the bottom of the unit. Heat pump condensers should be elevated enough to allow the water to drain. Sometimes the defrost thermostat just clips onto the coil. Occasionally they become loose and cannot sense the coil temperature, so they will not initiate a defrost cycle in weather that is above freezing. To check a defrost thermostat, just ohm it out. Generally, the defrost thermostat should close when it senses a temperature cold enough to initiate a defrost cycle. This can be checked by disconnecting the defrost thermostat from the circuit and ohming it out. If it is in the correct location, making good contact, and the coil is iced over, the defrost thermostat should be closed (0 ohms). If it is open (OL) it is bad. A thermistor defrost sensor is also checked by resistance, but these typically change resistance with temperature rather than opening and closing like a switch. You have to check the measured resistance against the manufacturer’s specs. Usually, these fail open, so if you have a measurable resistance, the defrost sensor is probably OK. Most defrost boards today have s test function. Jumping across the test pins accelerates time. If the defrost thermostat is closed, jump the test pins. If the board is good, it should initiate a defrost cycle. Do't automatically assume that the problem is a bad defrost board.Changing the board won't help if the problem is caused by one of the other causes.

New Regional Efficiency Standards Take Effect

In case you missed it, there are now new minimum efficiency standards for residential air conditioning equipment. As of January 1, 2015 the long discussed regional air conditioning standards went into effect. They are called regional standards because the minimum legal efficiency of the equipment is determined by the region of the country in which it will be installed. For Northern states, nothing changes – the minimum stays at 13 SEER. For the southeast, the minimum is increased to 14 SEER.  For the southwest, the minimum is a bit more complicated. The SEER rises to 14, but minimum EERs are also introduced. The minimum EER for the Southwest is 12.2 for systems less than 45,000 Btuh and 11.7 for systems 45,000 Btuh and greater. So a 13 SEER system that is legal in Indiana is illegal in Kentucky. A 14 SEER system that is legal in Texas might not be in Arizona, depending on its EER. Although the minimum efficiencies are already in effect, the enforcement mechanism has yet to be determined.

It is interesting to note that it is possible for a unit to have a higher SEER than another unit, but for the lower SEER unit to have a higher EER. That is the reason for the dual SEER/EER conditions.

Rheem has a good page with a map and a table explaining the new standards

http://www.rheem.com/products/heating_and_cooling/ReadywithrheemAC/

There is a very informative presentation on the California Energy Commision’s web site by Steve Kavanaugh explaining the reasoning behind using both SEER and EER for minimum efficiency standards.

Efficiency Explained

The Unexpected Gift

A little before Christmas I received a very unexpected gift. My son drove a couple of hours away to interview for a summer job. This was not just any job, but one in a summer camp in the woods – a bit off the beaten path. Later that day around 4:00 PM we got a call – he left the lights on, his car would not start, and he was unable to get it jumped. A friend offered to take him home, leaving his car there. We would need to retrieve the car later. At this point I was not exactly looking at this as a gift, but major nuisance. I could not be too mad because I have a tendency to do exactly the same type of thing. The next morning he and I got a new battery, loaded a bunch of tools in my car, and drove up to the woods to change the battery and get his car. Along the way we talked about his classes in college, world events, politics, and yes – car batteries. A two hour drive gives you a lot of time to talk. But truth be told, I enjoyed it. The battery in GM mini-van is in a horrid place: under the fuse box and a diagonal front brace. So there is a good bit of hardware to remove just to see the battery. I let him do most of the work – I just handed him tools. While we worked on the van I realized this was not a nuisance, but a gift. Instead of worrying about grades, curriculum, or schedules I received a day spent with my son. Priceless.