Information Database
For answers to commonly asked questions including comparison of competitive units and questions about referencing an existing specification visit our Frequently Asked Questions and Boiler Economizer Specification Compliance Information page.

On-Line Performance and Pricing Software

Bruce, our on-line sales engineer, can help you select a HeatSponge economizer and generate predicted performance, pricing, and even a proposal on-line right now. It only takes a few seconds.

Race Car Ride-And-Drive Offer

In a special incentive program any customer that places an order with a list price in excess of $ 200,000.00 with us will receive the opportunity to ride in a two-seat stock car and then have an opportunity to drive the car for 10 laps. Click below for more information.

Lose The Pocket Protector For A Minute

Just because we are very good boiler engineers does not mean we have to lose our sense of humor or ability to have a little fun during the day, nor does it mean we take our jobs any less serious. The daily grind can be stressful enough, everyone needs to be able to chuckle every now and then. Visit Super 'Sponge's MySpace page by clicking below

HeatSponge Boiler Economizers
Economizers Designed to Outlive Your Boiler
On-Line Pricing, Performance, and Proposal Generator
Featuring Bruce, Your On-Line Sales Engineer

This is Bruce's economizer data input page. The process for obtaining a quote is easy. If you have any questions as you proceed always feel free to ask Bruce, our on-line sales engineer, for helpful comments. Click the blue Info icon beside the parameter in question to ask for Bruce's information on the data field.

Bruce's "brain" currently consist of over 15,000 lines of code that reflects years of programming effort and represents a combined knowledge base from its creators of over a half of a century. We created Bruce to provide our customers the most complete and fastest economizer selection package that has ever been made available to the boiler industry.

Click here to meet Bruce, Your On-Line Sales Engineer

A brief tutorial is also provided for new users of this software. Click here for the Selection Tutorial.


Bruce's Required Data: this data is required to make a preliminary selection.

Need Advice on the Local Contact Data Field? Click to Ask Bruce

Select Your Local Contact: Required Data
Local sales and support offices are located all over the country to assist in the selection, procurement, and installation of a HeatSponge economizer.

Need Advice on the Boiler Capacity Data Field? Click to Ask Bruce

Enter Boiler Capacity: Required Data
You may enter your boiler capacity in Boiler Horse Power (HP), Boiler Pounds per Hour (PPH) capacity, or BTU input per hour (BTUH). Firetube boilers are typically rated in HP while watertube boilers are rated in PPH. Smaller commercial boilers rated in BTU input require the input to be entered in million BTU per hour, for example a 1,500,000 btu/hr unit should be entered as 1.5 in the data entry area.

Need Advice on the Inlet Water Temperature Data Field? Click to Ask Bruce

Economizer Inlet Water Temperature F: Required Data
Water inlet temperatures under 215 F will be considered non-deaerated - stainless steel tube required and will be included. Note if the economizer is to be used for a process water (non-boiler feedwater) application you will have the opportunity to enter a custom water flow rate lower on this page.

Need Advice on the Inlet Flue Gas Temperature Data Field? Click to Ask Bruce

Economizer Flue Gas Inlet Temperature F At High Fire: Required Data
If you're not sure:
Firetube: If unknown assume 75 degrees above saturated steam temperature
Watertube: If unknown assume 150 degrees above saturated steam temperature
Click here for steam tables to see saturated steam temperatures
Optional Part-Load Gas Temperature Inputs Available Below in Optional Input Section.

Need Advice on the Boiler Type Data Field? Click to Ask Bruce

Boiler Manufacturer Economizer Will Be Installed On: Required Input

We recommend you enter the manufacturer of the boiler if known as some boilers, primarily firetube boilers, have a lower tolerance for flue gas backpressure. Not selecting any specific manufacturer will result in the use of default data for the boiler type selected.

Mouseover for Additional Information Window

All performance based on counter-flow piping arrangement only.

End of required data requirements for typical HeatSponge Applications. This is a minimum requirement, final unit selection could be affected by other operational constraints. Additional data inputs are located below. HeatSponge reviews all selections for accuracy prior to placement of any purchase order.

Project Specific Input: Entered on a project-by-project basis.

Need Advice on Which Unit to Select? Click to Ask Bruce

Unit Recovery Type - BOSS, MAGNUM, SUPER, SHORTY, TITAN: Project Specific
SHORTY - Economy Coiled Unit - Typically under 300 HP Only
BOSS - Base Unit - Lowest Capital Cost Standard HeatSponge
MAGNUM - Mid-Size HeatSponge Designed to fit into the nitche between a BOSS and a SUPER
SUPER - High Recovery Unit - Higher Capital Cost Standard HeatSponge
TITAN - Very Large Boiler HeatSponge
BYPASS SHORTY: Select to disable automatic small boiler SHORTY selection while leaving AutoPick activated. Allows user the ability to check performance and pricing on BOSS and SUPER units on smaller boilers.

Mouseover for Additional Information Window

This provides the user an opportunity to select a unit configuration based on desired recovery and initial capital cost. If unsure leave default alone and Bruce will select the unit.

Existing Boiler Efficiency: Project Specific Input
You can change the efficiency of the existing boiler system. The default is 81%. The fuel mass flow rate calculations are based on this number so should not only be changed with care and knowledge.
Select Current Boiler Efficiency:


Boiler Stack Diameter: Project Specific Input
If you have entered a specific boiler model above the software will check the database to find the typical stack size for the given boiler. If you wish to override this number of enter a specific size for a unit not in out database you may enter it below. Leave at 0 for automatic select to work.
Select Boiler Flue Gas Diameter:


Enter Fuel Price ($/mbtu): Project Specific Input
Select the price of natural gas in dollars per million btu's.

Enter Annual hours of Operation: Project Specific Input
These hours will be reflected in each of the four load performance runs. There are a total of 8,760 hours in one year

Annual Hours at at Load Condition 1 - 100% Firing Rate: hours
Annual Hours at Load Condition 2: hours
Annual Hours at Load Condition 3: hours
Annual Hours at Load Condition 4: hours

Part-Load Firing Rate Selection: Project Specific Input
This is for changing the part-load firing rates. The default values are provided in the cells. The values cannot exceed 100 or be below 1.

Load Condition 1 Firing Rate: 100% Firing
Load Condition 2 Firing Rate: % Firing
Load Condition 3 Firing Rate: % Firing
Load Condition 4 Firing Rate: % Firing

Part-Load Flue Gas Temperature Input: Project Specific Input
The AutoPick software will automatically reduce flue gas temperature for typical applications. If you wish to enter specific flue gas temperatures at part-load firing rates you may do so below. NOTE ! If you do not want to enter other gas temperatures then leave these cells blank !

Gas Temperature at Load Condition 1 - 100% Firing: Entered Above in REQUIRED section
Gas Temperature at Load Condition 2: deg F
Gas Temperature at Load Condition 3: deg F
Gas Temperature at Load Condition 4: deg F

Burner Flue Gas Recirculation Rate: Project Specific Input
Enter the FGR rate only if your burner utilizes FGR and only if the FGR connection to the burner is downstream of the economizer. If your burner does not use any FGR then leave this cell blank. Typical Low NOx burners run 5% to 15%. Standard burners have no FGR so leave cell blank.

FGR Take-off Before or After Economizer: Project Specific Input
After Economizer
Before Economizer
You may select if the flue gas recirculation is taken through the economizer or extracted prior to the economizer. Extracting it after the economizer provides cooler flue gas to the burner however also means the economizer is physically larger and more expensive to accommodate the additional volume. There are advantages and disadvantages to both, consult your burner technician for support. The default is extraction prior to the economizer to allow for a lower capital cost.

Unit Fin Count: Project Specific Input
5 Fins per Inch - Gas Firing With Standby #2 Oil
4 Fins per Inch - Gas and Consistent #2 Oil Firing
3 Fins per Inch - Fuel Oil Firing
You may select 5 fins per inch if your plant fires gas with a #2 oil for standby use of less than one week annually. 4 fins for constant #2 oil firing, and 3 fins for heavy oil, #6, or other dirty fuels. If unsure leave at 5 fins.

Enter Blowdown Rate (%): Project Specific Input
This is the percent continuous (surface) blowdown. Enter if known.

Optional Input Section

Need Advice On The Custom Water Flowrate Data Field? Click to Ask Bruce

Custom Water Flow Rate (lbs/hr): Optional Input
Enter the water flow rate ONLY if the flow rate will differ from the boiler capacity flow rate. This feature is for economizers used in a non-traditional installation such as process water heating. If your application is a typical boiler economizer arrangement then leave this cell blank and leave units on PPH!
  • PPH - Enter an exact value in pounds per hour (PPH) non-deaerated water flow through the economizer
  • GPM - Enter an exact value in gallons per minute (GPM) non-deaerated water flow through the economizer
  • % of Make-Up - enter as a percentage number between 25 and 100 when using cold non-deaerated water prior to delivery to feedwater tank. Not valid for deaerated water flow to boiler.

BEI "Condense-O-Mizer" Dedicated Condensing Economizer: Optional Input
This overrides the selection criteria allowing for a true external condensing economizer application. The controls and fan are included in the preliminary proposal up to a certain size. Performance hint: to really get great performance out of these units take a look at using the Stack Economizers option.
Select Condense-O-Mizer dedicated condensing Unit

Stacked Economizers: Optional Input
Stack Units
Do Not Stack Units
Stacking economizers is a way of increasing heat recovery by placing two identical units on top of each other. The price will be double the price of the individual units. Stacking is to be utilized when very high heat recovery is required. Stacked units will also be much wider than a single unit as each unit will only be able to accommodate half of the allowable gas side pressure drop as a single unit would be allowed.

Target Flue Gas Outlet Temperature: Optional Input
Enter Target Gas Exit Temperature deg F
Stay with Model Selected
Increase Model Size
If you need a unit to meet a specific flue gas exit temperature enter the value in the above data field and Bruce will manipulate various designs to come as close as possible. The radio buttons allow Bruce to decide whether to stay with the model selected or increase model size in the event achieving the target gas temperature is not possible with the given model size selected. Selecting Increase Unit Size may not select the most cost effective unit so we recommend you do not change the radio button unless you consider changing model types as well to obtain the optimum unit selection.


Tube Material Override: Optional Input
Override ON
Override OFF
By default units with deaerated water will be supplied with carbon steel tubes, all other applications and all Shorty units have stainless steel tubes. Should you wish to override the carbon steel tube selection for deaerated applications and utilize a stainless steel tube click the button above. We do not permit the use of carbon steel tubes in any non-deaerated process.

End of required and optional data requirements for typical HeatSponge Applications. This is a minimum requirement, final unit selection could be affected by other operational constraints. HeatSponge reviews all of Bruce's prelimianry selections for accuracy prior to placement of any purchase order.


Only experienced boiler professionals should adjust the data below.

Manual Unit Selection / Bypass Bruce - For Experienced Boiler Technicians Only:
AutoPick ON
AutoPick OFF - Manual Selection below
Experienced boiler professionals may bypass Bruce's AutoPick software and manually select a maximum gas side pressure drop from the selection chart below. Just because a data page will be printed out means HeatSponge confirms that a manually selected unit will work on a given boiler. Excessive backpressure will seriously impact boiler operation.

This feature is also a very good way to compare the performance of a competitive unit to a HeatSponge. If you are comparing units and the competitive unit has a higher gas side pressure drop than our AutoPick selects use this feature to see how a HeatSponge would compare to the competitive selection. Some competitors will try to sell a smaller unit with an excessively high backpressure simply to offer a lower price.
Select Maximum Allowable Backpressure:


Flue Gas Mass Flow Calculation Override - For Experienced Boiler Technicians Only:
Experienced boiler professionals may custom select the flue gas mass flow rate. You must both enter the mass flow number to use as well as check the override checkbox.
Enter the custom mass flow rate in pph in this box
Bypass checkbox required


Alternate Water-Side Fluid Specific Heat - For Experienced Boiler Technicians Only:
Experienced boiler professionals may custom select the water-side fluid specific heat for non-water economizer applications. This would be typically utilized for glycol or thermal fluid heating applications. If your application is a typical boiler water application then leave at 1.0 and do not change anything!
Select Water-Side Fluid Specific Heat:


Maximum Water Side Pressure Drop: PSI For Experienced Boiler Technicians Only
You can change the maximum water side pressure drop that the economizer can accommodate.

Excess Air - For Experienced Boiler Technicians Only:
Experienced boiler professionals may custom select the excess air of the burner. Most typical burners operate at 15% excess air at 100% load.
Select Excess Air at 100% Load: %
Select Excess Air at 75% Load: %
Select Excess Air at 50% Load: %
Select Excess Air at 25% Load: %


Note: At this time our software is designed for rating boilers firing natural gas only. #2 oil performance will be close. Contact us if you require assistance.

The AutoPick software is based on the industry-standard Escoa approach to heat transfer. An industry standard, this proven and publicly available series of heat transfer equations can be relied on for providing accurate and consistent heat transfer ratings. All units that are awarded are further reviewed on a third-party software to insure accuracy with the preliminary online performance. We reserve the right to limit or deny access to the software for any reason and completely at our discretion.

Final unit selection could be affected by other operational constraints. HeatSponge reviews all selections for accuracy prior to placement of any purchase order.

Copyright © 2008 Heatsponge.com All rights reserved.



Selected Projects


Six BOSS HeatSponge's Ready for Shipment to a Central Heat Plant


Three BOSS HeatSponge's Manufactured Completely out of Stainless Steel Suitable for Full Condensing Operation - to be installed on Cl;eaver Brooks boilers


TITAN HeatSponge for installation on a Nebraska watertube boiler


BOSS HeatSponge installed on a Unliux Boiler at a commercial laundry facility


Six BOSS HeatSponge's Ready for Shipment to a Resort


Three BOSS HeatSponge's for installation on Superior Fire Tube Boilers at a Medical Center


SHORTY-4 HeatSponge for installation on a Cleaver Brooks boiler


A pair of SUPER HeatSponges for installation on Cleaver-Brooks watertube boilers at a college


A BOSS HeatSponge with a Canadian Registration Number CRN for installation in Canada


A BOSS HeatSponge supplied out of stainless steel for use in a condensing application


BOSS HeatSponge to be installed on a Cleaver Brooks 500 HP fire tube boiler


Another HeatSponge heading out to lower a customer's fuel bill
Boilerroom Equipment, Inc.
Copyright 2008, All rights reserved