Boiler house

TDS blowdown controls

Dimensions/weight

(approximate) in mm (ins) and kg (Ibs)

Spare parts

The spare parts available are detailed below. No other parts are

supplied as spares.

A

B

C

D

E

Weight

40

(1.57)

110

74.5

94.5

(4.33)

(2.93)

(3.72)

73

0.75

(2.87)

(1.65)

D

1⁄2" BSP/NPT

Available spares

Armature and spring set (kit).

Solenoid coil 230 V

Solenoid coil 110/120 V

How to order spares

E

A

Stock No. 4034080

Stock No. 4034081

Stock No. 4034082

B

1⁄2" BSP/NPT

Always order spares by using the description given in the column

headed 'Available spares' and state the valve type.

Example: 1 off Armature and spring set (Stock No. 4034080) for

a Spirax Spirax BCV20 blowdown valve.

Solenoid coil

Spring

Armature with

PTFE valve seat

C

Capacities

For conversion:

Cv (UK) = Kv x 0.963

Cv (US) = Kv x 1.156

Model BCV1 BCV20

Orifice size 3mm( ") 6 mm (1⁄4")

Kv value 0.25 0.8

When used for boiler blowdown purposes, the valve will be

controlling a mixture of water and flash steam, so the following

capacity table applies:

Boiler pressure

bar g

psi g

Capacities

kg/h

lb/h

kg/h

lb/h

BCV1

BCV20

1

14.5 175 385 560

1 232

2

29 250 550 790

1738

4

58 350 770 1120 2464

6

87 385 847

8

116 445 979

10

145 495 1 089

14

203 590 1 298

When the BCV20 valve is used as part of the BCS2 blowdown

control system, downstream of a steam trap, the following capacity

table applies:

How to specify

BCV1

Solenoid valves shall be Spirax Sarco normally closed blowdown

valve type BCV1 or BCV1 (UL/CSA) with brass bodies and

stainless steel valve seat with a PTFE seal.

BCV20

Solenoid valves shall be Spirax Sarco normally closed, low

pressure blowdown valve type BCV20 with brass bodies and

stainless steel valve seat with a PTFE seal.

Head

across valve

m

ft

Capacities

Cold water

Hot water

with flash steam

kg/h

lb/h

kg/h

lb/h

1

3 253 557 63

138

2

6 358 787 90

198

3

9 438 963 110

242

5

15 566 1245 142 312

10

30 800 1760 200 440

How to order

Example: 1 off Spirax Sarco BCV1 or BCV20 blowdown

valve having screwed BSP connections, 230 V 50-60 Hz.

TI-P403-60 AB Issue 5

BCV1 and BCV20 Blowdown Valves

2.4.4