Chromalox CHPES-6A manual Automatic Blowdown Instructions, If Furnished, Operation

OPERATION

AUTOMATIC BLOWDOWN INSTRUCTIONS		OPERATION— Set the “BOILER PROGRAMMED DUTY”
(IF FURNISHED)		switch to “BOILER ON” if the boiler is to be shut down each night.
The Automatic Blowdown is a device which automatically starts		Set it to “24-HOUR DUTY” if the boiler is to remain on continuous-
up your boiler in the morning; shuts it down at night and blows down		ly 24-hours per day (except during blowdown).
(partially drains) the main boiler drain and the low water cut-off col-		Set the tabs on the large timer for the ON and OFF times desired
umn for a predetermined time interval each working day.		for the boiler, screw in the small black day-skip tabs if is to remain off
The heart of the unit is an electrically operated straight through		during the weekend, etc.
type ball valve. It is specially designed to handle dirty, corrosive flu-		If the boiler is on 24-hour duty, set the OFF tab for the time that is
ids and particles without requiring cleaning or the use of a strainer.		desired for blowdown. Tzhe ON tab can be ignored, but must remain
Both the valve and the boiler are controlled by an electric control		on timer.
unit which indicates with pilot lights when the drain valve is in the		The small time delay relay controls the time that the drain valve
opened or closed position and when the boiler is ON or OFF. In addi-		remains open. The time is controlled by adjusting knob marked
tion to the automatic control function, the unit has a push button which		Blowdown cycle. Counterclockwise decreases, clockwise increases
momentarily de-energizes the boiler and opens the drain valve regard-		blowdown time. Time must be adjusted by trial.
less of the time of day.
	Timer

Boiler On

Valve Open

Valve Closed

Programmed Duty

24 Hour Duty

Manual Drain

Automatic Blowdown Control Cabinet

The unit may also be used to blow down boilers which run con- tinuously, day and night.

INITIAL TESTING — Set the switch marked “Programmed

Valve Actuator

duty/24 Hour duty” located on the panel box to the “ON” position.

On the large timer set the “ON” tab at about 8 AM and the “OFF”

tab at about 8 PM. Set the blowdown cycle dial at “O”.

Turn the large timer by hand until the “ON” tab passes the “TIME

NOW” indicator so the “TIME NOW” arrow indicates 10 AM.

Energize the main feed to the “LINE TERMINALS” of the unit.

The “BOILER ON” pilot light as well as the “VALVE CLOSED”

light should glow.

Hold down the “DRAIN” button for about six seconds. The

“BOILER ON” light should go out immediately as well as the

“VALVE CLOSED” light. It takes about 4 seconds for the drain valve

to open fully at which time the “DRAIN VALVE OPEN” light should

light. As soon as the “DRAIN” button is released the valve begins to

close. When it reaches the closed position, the “VALVE CLOSED”

Display View of Automatic Blowdown Control Cabinet

and the “BOILER ON” should light up again.

Now turn the wheel on the large timer until the “OFF” tab passes

Blowdown Cycle

the “TIME NOW” arrow. The “BOILER ON” light should go out and

Cycle

30's

Adjustment

the valve should begin to open. Once the “VALVE OPEN” light goes

0's

80's

on, the valve should remain open for a few seconds and then auto-

Boiler On

On/Off Switch

matically close. The “VALVE CLOSED” light should light and the

Support

“BOILER ON” light should remain off.

Valve Closed

Indicator Light

Terminal Block

2

Valve Open

7 Day Clock

3

Indicator Light

1FU

Clock

w

Support

15A

Prorammed Duty

B

3

1

A

7-Day Timer

Switch

Control

(2.3)

1

8

Relay

1 1CL

2

G

1TR

Ball Valve

24 Hour Duty

Control

PB Switch

Time Delay Relay

1CL

4

P

3

1PB

PR

1CR

B

1LT

(5)

6

R

Boiler On

Manual Drain

2

1

Y

Boiler Control

Fuse

3 2

6 2 10 2 7 11

8

1CR

Motorized

(3)

Replace with

Terminal Block

2PB

1TR

2LT

Amp Fuse Only

2B

4

Component Layout

2A

7

R

O/R

8

R

Valve Closed

Exterior Side

2

3

M

W

2

Blowdown Valve

BL

11 0

3LT

Valve Open

1A

1B

10

B

O/BL

R

Wiring Diagram for Automatic Blowdown

13