Installation & Operation Manual

11 Operating information (continued)

Ramp delay

For systems with lower flow, the SMART SYSTEM can limit the firing rate (when enabled) when a space heating call for heat starts, or when switching from a DHW call for heat to a space heating call for heat. There are six (6) limits that can be programmed, as well as six (6) time intervals corresponding to each limit. The sixth limit will also limit the firing rate for the rest of the call for heat.

Gradient limiting

If during operation of the boiler the outlet water temperature is rising too quickly, the control will reduce the firing rate to its lowest setting.

Outdoor air reset

With the outdoor air sensor connected, the control module will calculate the set points of the three (3) space heating demands based on the programmed reset curves. The installer can change the slope of the reset curves by several adjustable parameters. The user can limit the maximum set point for the system using the space heating set points.

Protection features

Outlet temperature, flue temperature, and temperature rise limiting

The outlet temperature is monitored by the boiler outlet temperature sensor. When the outlet temperature exceeds 185°F, the unit will reduce the fan speed. If the outlet water temperature exceeds 195°F the control will shut the unit down until it cools off.

The control module monitors the flue temperature by a sensor located in the flue exhaust. If the flue temperature exceeds 215°F the control will reduce the maximum fan speed. If the flue temperature exceeds 240°F the control will shut the unit down. The unit will restart automatically once the flue temperature drops 25°F and the minimum off time has expired.

The control monitors the temperature difference between the inlet and the outlet sensor. If this difference exceeds 55°F the control will reduce the maximum fan speed. If the temperature difference exceeds 60°F the control will shut the unit down. The unit will restart automatically once the temperature difference has dropped below 55°F and the minimum off time has expired.

Boost function

Freeze protection

If outdoor air reset is active, and any space heating demand has been active continuously for a set period of time (time adjustable by installer) and there has been no DHW demands, the control will increase the set point of that demand by a fixed number of degrees (adjustable by installer). This process will continue until the space heating demand ends, the set point reaches the programmed set point or a maximum of 20 increases has occurred. Once the system heat demand is satisfied, the set point will revert to the value determined by the reset curve.

Night setback

The controller may be programmed to reduce the space heating and DHW set points during certain times each week. Seven different start and stop times may be programmed for the space heating setback and seven start and stop times for the DHW setback. Any night setback scheduled within the next seven (7) days can be temporarily bypassed if desired.

Flame current support

To prevent nuisance shutdowns when the boiler is firing at minimum rates, the control will increase the firing rate when the flame signal drops too low.

DO NOT install the boiler in a room likely to freeze.

The following integral feature of the SMART SYSTEM control module provides some protection for the boiler only -- not for the system.

•The SMART SYSTEM control module provides freeze-up protection as follows when the boiler water temperature drops below 45°F:

•Below 45°F, the boiler and system pumps operate constantly.

•Below 37°F, the boiler turns on and runs at 20% of rate.

•Boiler and pumps turn off if boiler water temperature rises above 45°F.

•Lower temperatures may be programmed for systems with anti-freeze solutions (see the Knight Wall Mount Service Manual.

NOTICE

When system return temperatures

are maintained below the dew point,

 

condensation will form on the inside of the

 

boiler jacket causing some internal sheet

 

metal components to rust.

 

This feature of the SMART SYSTEM control

￿ CAUTION

module does not eliminate the possibility

 

 

of freezing. The installation must still

 

use recognized design, installation and

 

maintenance practice to prevent freeze

 

potential for the boiler and system.

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Lochinvar WH 55-399 operation manual Protection features
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WH 55-399 specifications

The Lochinvar WH 55-399 is a high-efficiency water heater designed for residential and commercial applications, offering a reliable solution for hot water needs. This model represents an advanced approach to water heating, combining cutting-edge technologies and features that ensure optimal performance and energy efficiency.

One of the standout features of the Lochinvar WH 55-399 is its high thermal efficiency, which is a key factor in reducing energy consumption and operating costs. With an efficiency rating exceeding 90%, this water heater ensures that more energy is converted into usable hot water, making it an environmentally friendly choice.

The WH 55-399 utilizes advanced condensing technology, which allows it to extract additional heat from the exhaust gases before they are expelled. This process not only increases efficiency but also significantly decreases greenhouse gas emissions. The unit is also equipped with an intelligent control system that allows for precise temperature adjustments, ensuring that the user has an optimal supply of hot water while maintaining energy savings.

Another important aspect of this model is its impressive recovery rate. The ability to quickly heat water after a significant draw ensures that users will not experience interruptions in their hot water supply, making it ideal for busy households or commercial environments. This is particularly beneficial in applications requiring consistent hot water availability, such as restaurants or athletic facilities.

The Lochinvar WH 55-399 is designed with durability in mind. Constructed from high-quality materials, this water heater boasts a robust tank lined with corrosion-resistant coatings, extending the lifespan of the unit and reducing maintenance needs. Additionally, it features a reliable gas burner and a well-insulated tank, contributing to its overall efficiency and performance.

Safety is also a priority with the WH 55-399. The unit incorporates multiple safety features, including a flame sensor, automatic shut-off valve, and over-temperature protection, ensuring peace of mind for users.

In summary, the Lochinvar WH 55-399 stands out with its combination of high efficiency, advanced technology, and durable construction. Whether for residential or commercial use, this water heater provides a dependable and cost-effective solution for all hot water needs. Its innovative design and performance characteristics make it a top choice for anyone seeking a premium water heating option.
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