Terminal Unit

Control (TUC)

Table 45—Continued. Fan Outputs not Energizing

Probable Cause

Explanation

No power to the TUC Autocycle test

The TUC requires 24 VAC power for the unit to operate properly.

The controller includes an auto cycle test sequence that verifies analog and binary output operation and associated output wiring. However, based on the current stage in the test sequence, supply fan may be off. Refer to the “Autocycle Test” section on page 71.

Wiring

The wiring between the controller outputs and the fan relays and

 

 

 

contacts must be present and correct for normal fan operation.

 

 

 

Refer to the typical unit wiring diagrams on pages 105-106.

 

 

Table 46. Valves Closed

 

 

 

Probable Cause

Explanation

 

 

Normal operation

The valves open and close to meet unit capacity requirements.

 

 

unit disabled

· The TUC may be disabled via the shutdown mode on a Tracer®

 

 

 

system or if BIP1 is configured as external interlock.

 

 

 

· During the stop modes, the valves remain closed unless freeze

 

 

 

avoidance is enabled and the fresh air temperature falls

 

 

 

below the freeze avoidance setpoint (configurable).

 

 

 

· If the fresh air temperature falls below the freeze avoidance

 

 

 

setpoint, the valves open. The TUC enables freeze avoidance

 

 

 

whenever the freeze avoidance setpoint is not zero.

 

 

Override present

The valves may be overridden to the closed position by either the

 

 

 

Tracer® system or by Everyware™ software. Whenever any override

 

 

 

is active, the TUC drives the valves closed unless they are concur-

 

 

 

rently overridden open.

 

 

Latching diagnostic presen

A specific list of diagnostics effects valve operation. For more

 

 

 

information, see the “Diagnostics” section on page 73. Latching

 

 

 

diagnostics require a manual reset to restore normal unit operation.

 

 

Autocycle test

The controller includes an autocycle test sequence that verifies

 

 

 

analog and binary output operation and associated output wiring.

 

 

 

However, based on the current stage in the test sequence, the

 

 

 

valve(s) may be closed. Refer to the “Human Interface” section on

 

 

 

page 62.

 

 

Maximum heating/cooling

The Tracer® may limit the maximum heating/cooling capacity of the

 

 

capacity of zero

TUC from zero to 100%. When the maximum cooling capacity is

 

 

 

zero, the cooling valve remains closed. When the maximum heating

 

 

 

capacity is zero, the heating valve remains closed.

 

110

UNT-IOM-6

Page 109 Page 111
Page 110
Image 110
Trane LO manual Valves Closed Probable Cause Explanation
Page 109 Page 111

LO specifications

Trane LO is a cutting-edge solution in the HVAC sector, designed with advanced engineering and smart technologies to meet diverse climate control needs. Renowned for its reliability and efficiency, Trane LO offers a wide array of features that set it apart in the market.

One of the core characteristics of Trane LO is its energy efficiency. Equipped with variable speed compressors, the system can adjust its output according to the cooling or heating demand, ensuring optimal energy use. This feature not only reduces energy consumption but also lowers utility bills for users. Additionally, Trane LO units often come with a SEER (Seasonal Energy Efficiency Ratio) rating that ensures top performance during hotter months.

Incorporating state-of-the-art technology, Trane LO features Smart Technology integration. Through IoT (Internet of Things) capabilities, users can monitor and control their HVAC systems remotely via smartphones or smart home devices. This feature promotes convenience and ensures that energy use can be optimized from anywhere, giving users greater control over their indoor climate.

Another standout technology in Trane LO is its use of environmentally friendly refrigerants. The system is designed to utilize low-GWP (Global Warming Potential) refrigerants, making it compliant with modern environmental standards and contributing to a greener planet.

The Trane LO also emphasizes durability. Constructed with high-quality materials, including weather-resistant finishes, these units are built to withstand various environmental conditions, ensuring they maintain peak performance over the years.

Noise reduction is another critical aspect of the Trane LO line. With features such as sound blankets and vibration dampening technology, the units operate quietly, ensuring that the comfort of users is not compromised by disruptive noise levels.

Maintenance is simplified with the Trane LO, as several units are engineered for easy access to essential components, promoting hassle-free servicing. This is vital for prolonging the lifespan of the system and reducing maintenance costs.

In summary, Trane LO represents a fusion of energy efficiency, advanced technology, environmental responsibility, durability, and user-friendly features. Whether for residential or commercial applications, Trane LO systems stand as a reliable choice for effective climate control.
Top Page Image Contents