Refrigeration

BTU designed refrigeration is industry leading by far in the Air system world.

1. The onboard computer control is second to none and offers the  following protections:
   • Surge Protection
   • Single Phasing Protection
   • Low Superheat/No liquid to compressor Protection
   • Overcurrent Protection
   • Crankcase Heater Alarm
   • Condensing Fan Alarm
   • Blackout/Brownout Protection 
     
     
2. Units have on board VFD control which provides the following advantages:
   • Tighter control: compressors can vary output from 50% to 120% without shutting off
   • Compressor protection: VFD has built-in faults that will stop the compressor if there are any issues
     
     

BTU ventilation has not lost a single compressor to date. 

BTU ventilation has had an independent power study done on VFD’s controlled compressors vs contactor and have shown 30% in power savings.

Our units are size properly for both maintaining the pile and to draw it down.  Which in our opinion, most refrigeration systems are not sized properly.

The season to season startup cost and maintenance are zero, our unit can be turned on with a flip of a switch “on demand” because of all the safeguards in place.

Typical units run on the on/off design approach.  This hammers the unit on/off multiple times a day causing unnecessary wear and tear, creating fluctuations in your plenum temperature. Our system scales from 120% down to 50% of compressor capacity, then will reverse load the building.  By opening the air doors up to 20% if necessary, this will keep the refer running and the plenum temperature dead on.

Refrigeration Features & Benefits

• BTU is the only system in the industry that polls all refrigeration data from HMI or remote access.  BTU also provides a data tunnel for technical assistance thru the panel.  Standard features include full records for refrigeration operation.
• BTU systems include auto unloading for high amp, high pressure, low suction and high temperature.  If any of these conditions occur the system will automatically start to unload to correct the issue
  • Example: High-ambient conditions, if pressures or temperatures get too high the system will unload just enough to control the parameters until the ambient temperature drops.
• BTU uses the latest electronic expansion valve control and communications.  BTU is the only company that has a custom electronic expansion valve controller.  This allows the evaporator to run at maximum efficiency.  The valves are run at the maximum opening to provide the most cooling and at the same time not have any liquid coming back to the compressor.
• All relays outputs have led indicators on them to provide for very easy troubleshooting.  All terminal blocks and wires are numbered to correspond to the electrical prints.

• On a two-compressor system, staging is coordinated between the two compressors.  Each compressor will run lead or lag to allow for equal run time.  As the refrigeration demand goes above what one compressor can handle the second compressor turns on.  In all other systems, this would add a big increase in cooling and possible cycle the second compressor on and off.  The BTU system will back the lead compressor down from 100% down to 50%.  The lag compressor starts at 50%.  This provides a smooth transition.  If the cooling demand continues to rise then both compressors will ramp up together.  As the cooling demand comes down and the lag compressor shuts off, the lead compressor will ramp back up to 100% for a totally smooth transition.
  
  
• Both the lead and lag compressors are constantly communicating.  If there is a problem with either system, the other will instantly respond and take control.