Hitachi RWM-(H)FSN3E, Service Manual

Page: 140 / 424

5 Control system
SMGB0070 rev. 1 - 08/2011
130
Outside temperature compensated (OTC) control for refreshing floor
The weather-dependent set-point field settings define the parameters for weather-dependent operation of the unit. When
weather-dependent operation is active the water temperature is determined automatically depending on the outdoor tem-
perature: higher outdoor temperatures will result in colder water and vice versa.
Ts
n
hc
Tsr
n
lc
Ta
n
lc Ta
n
hc
Water Outlet temperature set-point ºC
Outdoor ambient temperature ºC
Where:
Ts
n
hc: Temperature setting for max water temperature at low ambient temperature cooling
Ts
n
lc: Temperature setting for min water temperature at high ambient temperature cooling
Ta
n
lc: Low ambient temperature setting for max water temperature cooling
Ta
n
hc: High ambient temperature setting for min water temperature cooling
n: water circuit number (n= 1 or 2)
CODE REF Description Default Value Range Steps Units
CIRCUIT 1 (Direct circuit)
3-014 Ta1lc Low ambient Tº C1 23 17~30 1 ºC
3-015 Ta1hc High ambient Tº C1 32 31~45 1 ºC
3-016 Ts1lc Set-point at low ambient Tº C1 22 (3-020)~(3019) 1 ºC
3-017 Ts1hc Set-point at high ambient Tº C1 16 (3-020)~(3019) 1 ºC
CIRCUIT 2 (Mixed circuit)
3-114 Ta2lc Low ambient Tº C2 23 17~30 1 ºC
3-115 Ta2hc High ambient Tº C1 32 31~45 1 ºC
3-116 Ts2lc Set-point at low ambient Tº C2 22 (3-120)~(3119) 1 ºC
3-117 Ts2hc Set-point at high ambient Tº C2 16 (3-120)~(3119) 1 ºC
N O T E S
• Default values are the same for both circuits in order to prevent low temperatures in the Refreshing floor cir -
cuit.
• Parameters (3-0(1)20)~(30(1)19) are defined by Maximum and minimum water outlet temperatures selected by
installer.
C A U T I O N
• It is the installer’s responsibility to make sure no unwanted situation occurs (for example: water temperature
setting too low into floor refreshing).
• Be aware that the water set-point for circuit 2 will always be higher than water calculation for circuit 1.