
27
STRATA1
3 8 & 3 8 / 4 6 C O M B I
OS
AAV
SV
C
IV
IV
CWM
Strainer
DOC
DOC
DOC
Heating Pump
2A Max.
Vertical
Low Velocity
Mixing Header
Max Velocity 0.5m/s
Expansion
Vessel
Filling
Point
Condense
Waste
Heating Load
Strainer
Strata 1- 38 Boiler
or
Strata 1- 38/46 Combi
IV
IV
DOC
LSV
IV
IV
PS
OS =
Outside air temperature sensor.
Used where direct-on-boiler
weather compensated flow
temperatures are required.
C =
Room controls, either RE2132
modulating room unit from MHS
Boilers or a room thermostat.
PS =
Low water pressure cut off switch.
System pump to be no greater
than 2 amps
system type 3
Typical Single Strata 1 boiler installation serving heating only and using a low velocity
mixing header where system index resistance exceeds in-built boiler pump residual head -
see page 24. Flow temperature may be fixed/constant or weather variable.
17.0 hydraulic system design (contd)