Frequently Asked Questions

Why do I get an occasional spurt of air from my hot water faucet?

Your Heat-flo tank is equipped with a sacrificial anode rod, which deteriorates slowly over time, during which small gas bubbles form on the surface of the anode and release at a nearly imperceivable rate. If you have soft water, or a water softening system, the anode rod will deteriorate at a much higher rate, causing greater out-gassing. If the tank is idle for a long period, the gas will collect at a high point in the system, typically the faucet. Work with your water quality specialist to adjust the softness to an acceptable level.

What is the rating on an Indirect Water Heater? (Energy Rebates)

 You would put "not applicable" (n/a) since our units work off your furnace or boiler.

How do I find a distributor in my area?

Contact your local sales representative. Go to our Rep Locator page for a list of local area coverage.

I am a homeowner can I purchase direct from Heat-flo?

Heat-flo does not sell direct. Contractors can contact their local Heat-flo wholesaler.

What is the maximum temperature for my Indirect Water Heater? What is the recommended Temperature?

The maximum temperature is 150 degrees. The recommended and factory set temperature is 120 degrees.

How do I become a distributor of Heat-flo products?

To inquire about becoming a distributor please contact us at

How do I purchase a replacement anode rod?

Contractors can contact a local Heat-flo wholesaler.

What does a Heat-flo unit use for a heat source?

An Indirect Water Heater uses a furnace or boiler. The Storage tank uses a domestic water heating unit such as an on-demand type heater or combination boiler.

Can I register my unit online?

Yes, you can register your unit online on the Product Registration page.

Why am I getting brown/rusty water from the hot water only?

This is an indication that the anode rod in the unit has been completely consumed.

Can a unit be laid down to ship to end user location?

Laying down a tank for shipment is not recommended! Laying the tank on its side risks damaging the tank before it has arrived at its final destination. 

Can a unit be installed diagonally instead of vertically for tight space installations?

No, the unit would not work properly. This would cause the unit to constantly call for heat. Scald issues would occur.

What size expansion tank would my installation require?

The potable expansion tank size is determined by the volume of hot domestic water in the system.

Are Heat-flo units glass-lined or solid stainless steel?

All Heat-flo tanks are stainless-steel construction.

Who can I contact for Tech support, Customization, Sizing, Banking multiple units together, etc...?

Contact us at 508-278-2400 or email You can also contact your local sales representative.

Does my unit have an anode rod? If so, what type?

Heat-flo units have been manufactured with anode rods since approximately September of 2014. Heat-flo switched from magnesium anode rods to aluminum near the end of 2020. Please see question titled "How do I know if I have a Magnesium anode rod or an Aluminum anode rod?" for more details on telling the anode rods apart. 

What parts of the country do you ship to?

We ship to the 48 contiguous states, Alaska and Canada.

Where is the serial number located?

On the rating plate located above the drain valve.

If I have a well can we install a Heat-flo unit?

The all stainless steel construction of the Heat-flo tank is well water friendly.

Can my unit be installed outside?

Heat-flo tanks are not made to withstand the outdoors, therefore it is NOT recommended that the tank be installed outside.  

Can I make my own modifications?

Modifications can lead to the tank having a shorter life span, there fore we do not recommend altering the tank under any circumstances. 

Can I use my wood stove as a heat source for my unit?

YES, providing that the water temperatures are properly controlled.

I am not a contractor can I install the unit myself?

Water heaters should be installed by a licensed professional. This is to ensure the tank is installed properly, up to code, and can last for a long time. 

How do I know if I have a Magnesium anode rod or an Aluminum anode rod?

An aluminum anode rod will have the letter “A” on the brass nut. You can also tell the type of anode rod by when it was produced. If it was produced before the last couple months of 2020, you have a magnesium anode rod, but if it was produced after late 2020 you most likely have an aluminum anode rod.

Are the older and newer anode rods interchangeable?

Yes! All Heat-flo anode rods are interchangeable. 

What size socket is needed to remove the Anode Rod?

Our anode rod nut has changed to make the size more universal!

If you have a tank with a larger nut, it will need a 1 ¾ “ socket to remove it.

If you have a tank with a smaller nut, it will need a 1” socket to remove it.

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