The piston is lifted by the cold water supply. If the cold water supply
stops the piston will fall, closing the steam valve. To sustain this
design integrity the piston must move freely. Scale build-up will
prevent movement and regular maintenance must be carried out
to ensure the valves safe operation.
Range
The MkII Spirax Sarco steam / water mixing station is designed to
provide hot water economically by blending steam and cold water
quickly to the required user temperature. The temperature can be
changed by turning the adjustment knob. As the valve is not
thermostatically controlled, in order to maintain a fixed hot water
temperature the cold water pressure and flowrate must be
constant. The installer must ensure that the Local Water Board
Regulations are adhered to, with regard to direct use of mains
water supply. MkII valves are supplied from 2002 onwards.
Steam
Operation
inlet
The mixing valve employs a piston to lift and open the steam valve.
Cold
water
inlet
The TCO1 temperature cut-out valve activates at a temperature of
95°C to limit the discharge of steam in the event of a system fault.
Each steam / water mixing station is supplied with isolation valves,
pressure gauges, syphons and cocks, steam traps, check valves,
union joints, strainers, thermometer and TCO1 temperature
cut-out valve.
1⁄2" and 3⁄4" stations can be supplied with an optional high quality
hose, hose rack and gun for hosedown purposes, see TI-P157-05
and TI-P157-22. High capacity 1" and 11⁄2" stations are intended
for fixed installation such as periodic filling of tanks and therefore
no hoses or guns are available.
Hot
water outlet
Hosedown gun, hose and hose rack (for 1⁄2" and 3⁄4" valves only)
Mixing
Check valve
Ball valve
Strainer
Dial thermometer
Pipe fittings
Temperature
cut-out valve
Pressure gauge
Steam trap
Bronze
Carbon steel
Brass
Stainless steel /
Brass / Bronze
Bronze
Mild steel
Brass
See TI-P029-01
See TI-P133-06
See TI-P164-01
Brass
See TI-P157-18
See TI-P027-01
See TI-P122-01
refer to TI-P157-05.
valve
Hose reel (for 1⁄2" and 3⁄4" valves only) refer to TI-P157-22.
See
1⁄2", 3⁄4", 1" and 11⁄2" screwed BSP (inlet and outlet)
Size
1⁄2"
3⁄4"
1"
11⁄2"
Range °C
Hot water outlet
40 to 90
40 to 90
40 to 90
40 to 90
(approximate) in mm and kg
Size
A
B
C
D
E
Weight
1⁄2"
655
613
120
295
96
13.7
3⁄4"
713
671
130
440
94
15.9
1"
932
867
190
530
125
23.8
Mixing valve pressure/spring ranges
Size Spring
Yellow
1⁄2" Green
Black
Red
3⁄4" Blue
White
Red
1"
Blue
White
Red
11⁄2" Blue
White
Steam inlet
Pressure bar g
7.00 to 10.3
3.50 to 7.0
0.35 to 3.5
7.00 to 10.3
3.50 to 7.0
0.35 to 3.5
7.00 to 10.3
3.50 to 7.0
0.35 to 3.5
7.00 to 10.3
3.50 to 7.0
0.35 to 3.5
Minimum cold waterflow
l/min to open steam valve
4.5
2.7
2.2
8.1
6.8
6.8
36.3
31.8
27.2
54.4
54.4
54.4
11⁄2"
1 214
1 154
400
800
148
45.5
C
E
D
Note: Valves are supplied with the intermediate pressure range
spring fitted.
Example: 1 off 1⁄2" Spirax Sarco MkII steam/water mixing station.
Local regulations may restrict the use of this product to below the conditions quoted.
In the interests of development and improvement of the product, we reserve the right to change the specification without notice.
© Copyright 2013
TI-P157-08
Pipeline
Flow l/min
fittings
Minimum to Maximum
2.2 to 108
6.8 to 200
27.3 to 375
54.4 to 550
A
B
ST Issue 9