Tip summary • An economizer is a heat exchanger that is designed to use heat from hot boiler flue gases to preheat water. • Economizers are often used on large utility steam boilers to preheat the feed water using recovered stack heat. The same principle can be applied to smaller heating boilers where there is a nearby demand for hot water. • These installations have become more economical as energy prices are increasing and smaller, lighter and more durable economizers have been developed. • A condensing economizer improves the effectiveness of reclaiming flue gas heat by cooling the flue gas below the dew point. • The condensing economizer thus recovers both the sensible heat from the flue gas and the latent heat from the moisture that condenses. • The condensate is highly corrosive and requires measures to ensure that it does not enter the boiler and proper material selection. New boilers generally include economizers. • Three major parameters are considered in evaluating all boiler economizers are: o fuel type o acceptable backpressure on the exhaust o Inlet water temperature Proposed actions o Flue gases content and boiler efficiency o Evaluate the possibility and type of economizer that can be installed. o Evaluate the economics of the required changes. Economics o System retrofit will have a medium cost with quick ROI. Savings o Estimated energy savings range: 5% to 12% of boiler energy use based on type used. Conclusion o Boiler feed water Economizer can improve boiler efficiency by 5% or more but it needs careful evaluation. o Please share this tip with others to share knowledge and increase energy efficiency awareness. o Please contact me for any advice or support about this issue or other energy management issues.

1. What are the benefits of installing a Boiler
Feed water economizer?
(Energy Efficiency Tip of the Day)

2. Tip

3. Install economizer as it recovers heat
from hot flue gases and preheats boiler feed water

4. Heat losses

5. Consider
Fuel type
Acceptable backpressure on the exhaust
Inlet water temperature

6. Actions
Review your current boiler efficiency and flue gas content
Evaluate the Possibility to install Economizer
Evaluate the economics of the required changes.

7. Economics Medium cost high ROI

8. Savings
5 % to 12% improve in Boiler
efficiency based on type.
Save the Environment

9. Please share it with others and for more visit
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