Table of Contents
Advertisement
With an outdoor temperature-dependent frost threshold
temperature (
) with or without the effect of room
temperature , the following applies:
•
If the outdoor temperature exceeds the set threshold
temperature by 2 °F (1 K / °C) and there is no heat demand
from the heating system, the heating pump switches off.
•
If the outdoor temperature drops below the set threshold
temperature, the heating pump switches on (system frost
protection).
With a room temperature-dependent frost threshold
temperature, the following applies:
•
If the room temperature exceeds 45 °F (7 °C) and there is
no heat demand from the heating system, the heating
pump switch is off.
•
If the room temperature drops below 41 °F (5 °C) the
heating pump switches on (no system frost protection).
With a room- /outdoor temperature-dependent frost threshold
temperature (
), the following applies:
•
If the room temperature drops below 41 °F (5 °C) or if the
outdoor temperature drops below the set threshold
temperature, the heating pump switches on (system frost
protection).
The by Room Temp. setting does not offer
absolute frost protection, because piping
installed in soffits, for instance, can freeze.
This can happen even though the temperature
in the reference room is considerably above
41 °F (5 °C) as the result of outside heat
sources. If an outdoor temperature sensor is
installed, frost protection can be assured for
the entire heating system regardless of the
control type set:
▶ In the Frost protect menu, set either by
Outdoor Temp or Room - Outside (
CRC200
Set the heating system and heating curve for outdoor reset
control
▶ Heating type (High Temp or Low Temp. heating) in the
System Data > Heat. System menu. Adjust the system.
▶ Set the control mode (optimized or simple heating curve) in
the System Data > Control type menu (
Menu items that are not required for the selected heating
system and control mode are hidden.
The heating curve is the decisive basic factor for an economic
and convenient operation of the heating system with outside
temperature compensated control. To calculate the heating
curve, the control system requires you to enter a number of
parameters for the heating system, from which it automatically
calculates the optimum heating curve by means of a
mathematical formula.
This calculation takes into account the "damped" outside
temperature and the room control temperature. The room
control temperature is an internal parameter based on the
desired room temperature (set room temperature) and the
room influence factor.
This allows the end customer to influence the heating curve
directly by modifying the set room temperature.
The most important settings are the design temperature,
maximum supply temperature and minimum outdoor
temperature.
The heating curve ( fig. 13 and 14) is determined by the
base point and end point. The base point exists with an
adjusted outside temperature of 68 °F (20 °C) with a supply
temperature of 77 °F (25 °C) (at a room temperature of 70 °F
(21 °C)). The end point of the heating curve must be set
according to the design temperature of the heating system.
The gradient of the characteristic heating curve (slope) is
determined by the parameters Min.outs.temp (the lowest
outdoor temperature expected in a particular region; page 18)
).
and the Design Temp (the supply temperature which is to be
reached at the minimum outside temperature) ( fig 13
and 14, left).
The heating curve can be shifted up or down in parallel by
matching the set room temperature ( fig 13 and 14, right).
Service menu | 21
).
6 720 821 651 (2017/05)
Hide quick links:
Advertisement
Table of Contents
