by High Performance HVAC | Technical Reference |
Common Sense Safety HVAC Codes - Some HVAC Installation technicians take pride in their work and make any installation job they perform look like a work of art. There are others who don’t care and want to install the unit as quickly as possible and move on down the road to the next job so they can do the same.
It really does not take much more time to do things right in the first place including reading the instruction manual that comes with every new condenser or air handler (actually all new HVAC equipment comes with instructions for installation). (more…)
by High Performance HVAC | Direct Digital Controls |
Alerton BTI DDC Controller Building Automation - This is the main DDC controller for Alerton. It communicates with all the other controllers in the field serving the building automation system and connects those systems with a computer or modem. (more…)
by High Performance HVAC | Direct Digital Controls |
DDC Programming Logic 3 - DDC control logic blocks have practically an unlimited way of arranging the blocks for HVAC control. Below is an example of a line of logic blocks arranged for static pressure control of a VAV air handler supply fan using a variable frequency drive. This same arrangement could also be used for static pressure control using a bypass damper instead of a VFD. (more…)
by High Performance HVAC | Direct Digital Controls |
Programming DDC Logic 2 - Analog Network Input
Programming DDC Logic 2 - The analog network input is similar to an analog input except this input is not hardwired to the local controller but on a remote controller in the network. It is very important that the communication works effectively for this analog network input to work. An example of this is the outside air temperature which is hardwired to a DDC controller in the penthouse of a multistory building.
The building engineer only wants the boilers to fire if the outside air temperature is less than 55° F. Instead of having an outside air temperature device hardwired to the boiler controller an analog network input can be placed into the boiler controller program and linked to the outside air temperature reading which is in the penthouse controller where the outside air temperature thermistor is hardwired. This saves devices and wires necessary for optimum control.
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by High Performance HVAC | Air Handlers |
Air Handler Components. This article will take different types of air handlers and disassemble them part by part. This will give you a good description of each part and hopefully a better understanding of the air handler. Most of the components associated with the air handler are in the air handler. However, there are a few components which are not in the air handler but associated with the air handler.
There are some hot water and cold water coils which are not fixed in the air handler. They are downstream in the ductwork. There are also some gas and electric duct heaters which are mounted in the ductwork. They are completely reliant on the air handler for air flow. These systems will also be covered. Hopefully, this article will offer you a comprehensive look at the air handler, all its parts, and how it functions. (more…)
by High Performance HVAC | Air Handlers |
Air Handler Filter Pressure Sensor - This is a pressure sensor. It tells a maintenance technician if the air filters are dirty and clogged. The pressure control is a low static pressure switch to trip the unit if the mixing box drops below the setpoint pressure. The pressure the switch is calibrated to.
In addition, the low static pressure sensor protects the fan and the ductwork including dampers from damage. If the economizer damper and the return air damper would fail closed (or another possible scenario) that would cause the unit to pull negative pressure in the mixing box. (more…)
by High Performance HVAC | Air Handlers |
Water Dripping from Air Conditioner - We have 2 air conditioning units in our house and 2 pipes protrude from the roof. One of the pipes is dripping water. We were told to look for a blockage and to empty the pans. I don’t see where to check for a blockage. Any suggestions?
The air conditioning units we have: Bryant models 373LAV, 376CAV Downflow/Horizontal and 383KAV, 395CAV Upflow Gas Furnace. (more…)
by High Performance HVAC | Air Handlers |
HVAC Duct Work delivers the conditioned air to the spaces. The Air Handling Duct channels this conditioned air to spaces where it is needed and then a return duct channels the air back to the air handling unit duct for re-conditioning. The return ductwork has a negative pressure while the supply ductwork has positive pressure.
In commercial systems and tight residential homes, it is necessary to add fresh air to this conditioned air so the air remains fresh and healthy for the occupants of the structure. This is required by the mechanical code and often this air comes through ductwork from the outside. (more…)
by High Performance HVAC | Buyers Advice, Goodman HVAC Reviews, Trane HVAC Reviews |
Goodman versus Trane Air Conditioners - The first thing we need to do when comparing a Trane Versus a Goodman air conditioning system is to make sure we are comparing similar models with similar features. Each manufacturer makes various models from a builder’s grade unit, which is usually the HVAC manufacturer’s cheapest model up to the unit that has bells and whistles, and some of these have bells and whistles for the bells and whistles. You want to make sure you are comparing apples to apples and not an apple to an orange.
The next thing we need to do when comparing HVAC equipment is to look at the HVAC contractor installing the equipment. If you get a lousy installer or contractor, forget about the name brand because the HVAC system WILL NOT FUNCTION CORRECTLY and EFFICIENTLY if the installation is shoddy. Also, the unit will not have the same life expectancy, will fail prematurely, and will need replacing sooner than if the HVAC equipment is installed properly in the first place. Out of any buyers advice about air conditioning and heating equipment that someone can give you this is probably the most important part.
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by High Performance HVAC | Duct Work |
HVAC Duct Systems - Ductwork systems channel the air to the spaces where it is needed from the air handler. HVAC duct systems also will pull the air from the space and channels it back to the air handler where it needs to be conditioned. In some commercial applications, the area above the ceiling is considered the return duct. All the return air is channeled back to the air handler through the plenum where it is conditioned in the air handler. Part of the conditioning process is the air being passed through an air filter and then an exchanger like a coil or heat exchanger. (more…)
