Tekmar Universal Reset Control 363 Скачать руководство пользователя страница 4

Страница: 4 / 40

4 of 40

Section A —General Operation

POWERING UP THE CONTROL

When the Universal Reset Control 363 is powered up, the control displays the control type number in the LCD for 2 seconds. Next, the
software version is displayed for 2 seconds. Finally, the control enters into the normal operating mode and the LCD defaults to displaying
the current outdoor air temperature.

CHARACTERIZED HEATING CURVE OR RESET RATIO

The 363 has two methods of varying the supply water temperature based on the outdoor air
temperature. The installer can select either a

Characterized Heating Curve or a Reset Ratio.

Characterized Heating Curve

The

Characterized Heating Curve method of controlling the supply water temperature

based on outdoor air temperature and optionally indoor temperature is the most accurate.
The control takes into account the type of terminal unit that the system is using. Since
different types of terminal units transfer heat to a space using different proportions of
radiation, convection and conduction, the supply water temperature must be controlled
differently. Once the control is told what type of terminal unit is used, the control varies the
supply water temperature according to the type of terminal unit. This improves the control
of the air temperature in the building.

Reset Ratio

The

Reset Ratio method of controlling the supply water temperature is based solely on the

outdoor air temperature. This method does not take into account the type of terminal unit
that the heating system is using and therefore is not as accurate as a

Characterized Heating

Curve.

TERMINAL UNITS (

Boil TERM

MIX TERM

)

When using a

Characterized Heating Curve, the control requires the selection of a terminal

unit. The terminal unit determines the shape of the

Characterized Heating Curve according

to how the terminal unit delivers heat into the building space. The 363 provides for selection
between six different terminal unit types: two types of hydronic radiant floor heat, fancoil, fin–
tube convector, radiator, and baseboard.

Hydronic Radiant Floor

(

HRF 1

)

HRF1

is a heavy, or high mass, hydronic radiant floor system. This type of a hydronic radiant

floor is embedded in either a thick concrete or gypsum pour. This heating system has a large
thermal mass and is slow acting.

Hydronic Radiant Floor

(

HRF 2

)

HRF2

is a light, or low mass, hydronic radiant floor system. Most commonly, this type of

radiant heating system is either attached to the bottom of a wood sub floor, suspended in
the joist space, or sandwiched between the subfloor and the surface. This type of radiant
system has a relatively low thermal mass and responds faster than a high mass system.

Fancoil

(

COIL

)

A fancoil terminal unit or air handling unit (AHU) consists of an hydronic heating coil and
either a fan or blower. Air is forced across the coil at a constant velocity by the fan or blower
and is then delivered into the building space.

Sequence of Operation

Sequence, Section A

Characterized Heating Curve

Outdoor DSGN

Increasing W

ater

emperature

MIX

BOIL DSGN

Decreasing Air Temperature

MIX

BOIL
INDR