Standard Features

• Constructed of high quality corrosion resistant stainless steel (AISI316), with stainless hardware
• Rolled formed to shape and then precision welded
• Specially designed built-in flow restrictor to assure maximum heat exchange
• Designed to minimize pressure loss in the heating system
• Leak tested to assure that they are totally functional
• Compact in size and require a minimum installation space and are lightweight
• Significant energy savings

1. A source of hot water (gas-, oil-, or coal-fired boiler or hot water heater).

2. A bypass loop that circulates water from the pond, through the exchanger, and back to the pond.

3. A hot water supply loop that circulates the heating water through the exchanger, and back to the boiler.

4. A thermostat that activates the circulator on the hot water supply loop.

The Maxi-Flo exchangers are stainless steel, and are manufactured in Sweden.  They are available in five sizes, ranging from 95,000 to 400,000 BTU/hr thermal output.  They are designed for an average difference of 100 degrees Fahrenheit between the boiler and pond waters.

Sizing Guide: how much heat does your pond require?

Step 1: determine your pond capacity

Rectangular Ponds:
Capacity (US Gallons) = 7.5 X Length X Width X Average Depth
                                          (all measurements in feet)

Circular Ponds:
Capacity (US Gallons) =5.9 X Diameter squared X Average Depth
                                         (all measurements in feet)

Step 2: select Maxi-Flo Heat Exchanger required from Table #1
Find your pond capacity in the table below and select the Maxi-Flo heat exchanger and its recommended boiler output capacity:

Suggested installation of the Maxi-Flo

Method 1. Heat loss calculation for uncovered pond:

Heat loss (Btu/hr) = 12 X pond surface area X desired pond temp.- coldest ambient temp.

Method 2. Heat loss calculation for covered pond:
Make sure an airspace is maintained between the surface of the pond and the cover. Do not float the cover directly on the pond.

Heat loss (Btu/hr) =  pond surface area X desired pond temp. - coldest ambient temp.

Use table #2 to confirm that the exchanger size you selected in step 2 is adequate

*Prices do not include shipping or installation.

Sample calculation:

Determine the boiler output and size heat exchanger required for a 20' long by 9' wide by 3' average depth pond.  The coldest air temperature anticipated is 25°F, and we intend to maintain 70°F in our pond.

Step 1.  Pond capacity calculation

Pond capacity = 7.5 gallons/square ft X 20 feet X 9 feet X 3 feet = 4050 gallons

Step 2.  Select the  model required from table #1

Checking table #1, 4050 gallons would require the use of the model MF-80, and would require a boiler output of 33366 BTU/hour.

A cutaway view of the Maxi-Flo heat exchanger

Method 1. Heat loss calculation for uncovered pond

Surface area = 20' X 9' = 180 square feet

Heat loss = 12 X 180 X (70-25)= 97200 BTU/hr

Now use table #2 to verify is model selected above is adequate if pond is uncovered.

Table #2 indicates the usage of model MF-135.  Since the calculated output of 97200 BTU/hour is only slightly higher than the MF-80 maximum output of 95000 BTU/hour, you could use model MF-80.

Method 2. Heat loss calculation for covered pond

Heat loss =  180 X (70-25)= 8100 BTU/hour