Controls Setup for Microchannel Coils (TSDC Only)
The TrilliumSeries™ Adiabatic Condenser is the most efficient product in its class and as
such it has very unique characteristics that need to be taken into account when integrated
into a traditional refrigeration system. It is capable of maintaining a steady drop leg
pressure in the system year long without the need of floating set points or periodically
adjusting flood valves to control capacity on colder days. It is important to monitor
the condenser to avoid rapid cycling of the fans, more specifically when the ambient
temperatures drop below freezing.
During the colder season the condenser becomes more efficient and the hot gas entering
the coils condenses much faster. During these conditions the drop leg pressure and
temperature may fluctuate rapidly if the control system is not properly tuned. This rapid
fluctuation will produce a significant amount of cycling of the condenser’s fan motors.
This rapid cycling will not only increase the cost of operating the unit but also cause
severe stress on all mechanical components which could lead to costly repairs. As with
other refrigeration equipment, care should be taken in the setup of the control system to
ensure the fan motor is started from rest no more than 6 times per hour. Excess cycling on
cold days can thermally shock the microchannel and can cause premature deterioration,
leading to failure. Coil failure due to excessive system cycling is not covered under
warranty. This excess cycling will also manifest wear on other parts of the refrigeration
system such as compressors and valves.
To avoid excess cycling, ensure the control system is properly tuned for a condenser with
low refrigerant volume. Typical PID (Proportional Integral Derivative) control settings may
be tuned by default for larger volume condensers and may respond erratically when placed
in service with a microchannel condenser without tuning. Check with your controls vendor
for custom microchannel settings. In some cases, Proportional only (sometimes called
‘Linear’) control, based on the dropleg temperature or pressure, is a stopgap solution
until proper Integral & Derivative settings can be determined. Alternatively, installing the
TrilliumSeries™ Adiabatic Condenser with the ‘Head Pressure Control’ option eliminates
fan fluctuations by taking over fan control from the refrigeration system and ensures steady
year-round operation and protection against erratic refrigeration system control. For more
information, see pages 15, 23, and 32.
WWW.BALTIMOREAIRCOIL.COM
23
NOTICE: Excess cycling on cold
days can thermally shock the
microchannel and can cause
premature deterioration, leading to
failure.
NOTE: It is recommended to set the
hold back valve to 10 PSI below the
controller’s setpoint
Installation
Controls Setup for
Microchannel Coils
To Next Page
Loading...
Need help?
General
