Blowdown Procedures; Main Boiler Blowdown - FULTON RB Series Installation, Operation And Maintenance Manual

MAINTENANCE - 4
4.5

BLOWDOWN PROCEDURES

Keep the boiler, water level gauge (sight glass) and interconnecting pipework free from sludge
and scale build-up by following these blowdown procedures.
Note: Where a boiler is operating continuously at steam pressure, advice should be sought from Fulton Service
Department regarding the appropriate blowdown procedure.
4.5.1

MAIN BOILER BLOWDOWN

1. Start the boiler and generate not more than 10 psi of steam (see note).
2. Shut off both the burner and the pump.
3. Fully OPEN the boiler main blowdown valve for not more than 5 seconds, or as recommended
by the water treatment specialist.
4. CLOSE the valve.
Note: Where high levels of suspended solids are produced, longer and/or more frequent blowdown may be
required.
Auto Blowdown/Draining
The boiler may be drained by opening the boiler blowdown isolation valve, having mechanically
opened the auto blowdown valve (see Section 3.4 - Draining the Boiler).
Note: As well as removing sludge (suspended solids) from the boiler, a second and equally important function
is to maintain the TDS (totally dissolved solids) level to within the required limits. The amount of blowdown, and
hence time required, is dependent on the amount of TDS in the raw water supply, the percentage condensate
return, water treatment chemicals added and the number of hours a day operation. In order to establish
the required blowdown rate, consult your water treatment specialist who will recommend a water treatment
programme in terms of appropriate chemicals and the required blowdown rate which takes these factors into
account.
Automatic boiler
blowdown valve
Pneumatic
actuator
Note: The boiler blowdown shown is an automatic installation, manual blowdown is also available.
Page 32
Figure. 20 - Main Boiler Blowdown Valve
Fulton Ltd
Boiler blowdown
isolation valve
RB-RBC-IOMM-2015-1