---
title: How to Combat Iron Oxide in Hydronic HVAC Systems
description: Iron oxide and magnetite can disrupt heat transfer and reduce system efficiency in an hydronic HVAC system, making removing the iron-oxide a must.
image: https://blogs.heattransfersales.com/hubfs/Screenshot%202019-02-06%2010.46.26.png
---

[![HTS_Logo_RGB_and_White](https://blogs.heattransfersales.com/hs-fs/hubfs/HTS_Logo_RGB_and_White.png?width=270&height=81&name=HTS_Logo_RGB_and_White.png "HTS_Logo_RGB_and_White")](http://www.heattransfersales.com)

- [Home](https://heattransfersales.com/)
- [Products](https://heattransfersales.com/products) 
    - [Manufacturers Represented](https://heattransfersales.com/products)
    - [Packaged Systems](https://heattransfersales.com/products)
- [Customer Service](https://heattransfersales.com/customer-service) 
    - [Parts](https://heattransfersales.com/parts)
    - [Pump Repair](https://heattransfersales.com/pump-repair)
    - [Service](https://heattransfersales.com/service)
- [Pump'nFlo](https://heattransfersales.com/pump-nflo)
- [Resources](https://heattransfersales.com/resources) 
    - [Training](https://heattransfersales.com/training)
    - [Sustainable System Concepts](https://heattransfersales.com/sustainable-system-concepts)
    - [Airside HVAC](https://heattransfersales.com/hvac-equipment)
    - [Plumbing Equipment](https://heattransfersales.com/plumbing-equipment)
    - [Building Automation](https://heattransfersales.com/building-automation)
    - [Blog](https://blogs.heattransfersales.com/blog)
- [Careers](https://heattransfersales.com/careers)
- [About Us](https://heattransfersales.com/about-us) 
    - [History](https://heattransfersales.com/history)
    - [Privacy Policy](https://324b4bc7-5729-4ace-b8c0-bc77b425b76e.filesusr.com/ugd/ff46b9_f6100e8b535d465f9fb060f60f8049cc.pdf)
    - [Terms of Use](https://324b4bc7-5729-4ace-b8c0-bc77b425b76e.filesusr.com/ugd/ff46b9_8a108a4c73734c8ca00866bdecf7cb60.pdf)
- [Contact](https://heattransfersales.com/contact)

### Topics

- Select a Topic

### Stay up to date

 SUBSCRIBE TO OUR BLOG

### Stay up to date

[General Knowledge](https://blogs.heattransfersales.com/blog/topic/general-knowledge) [Building Owner Tips](https://blogs.heattransfersales.com/blog/topic/building-owner-tips) [Design Engineer Tips](https://blogs.heattransfersales.com/blog/topic/design-engineer-tips) [Filtration](https://blogs.heattransfersales.com/blog/topic/filtration) [Efficiency](https://blogs.heattransfersales.com/blog/topic/efficiency)

# Removing Iron Oxide in Hydronic HVAC Systems

![Picture of Kelly Patterson](https://blogs.heattransfersales.com/hubfs/Blog_images/10801587_10152577444568382_8583161712827376882_n.jpg)

 By [Kelly Patterson](https://blogs.heattransfersales.com/blog/author/kelly-patterson) on June, 30 2021

[mailto:?body=https://blogs.heattransfersales.com/blog/how-to-combat-iron-oxide-in-hydronic-hvac-systems-0](mailto:?body=https://blogs.heattransfersales.com/blog/how-to-combat-iron-oxide-in-hydronic-hvac-systems-0)

![remove iron oxide](https://blogs.heattransfersales.com/hubfs/Screenshot%202019-02-06%2010.46.26.png)

![ADEY Magna Clean shows sludge](https://blogs.heattransfersales.com/hs-fs/hubfs/Screenshot%202019-02-06%2010.46.26.png?width=146&name=Screenshot%202019-02-06%2010.46.26.png)Air in a hydronic HVAC system can be a problem, specifically when it comes to the development of corrosive iron oxide.  When system components, like pump volutes or expansion tanks, made of cast iron or steel are mixed with oxygen and water, corrosive iron oxide is formed.  Commonly known as "black sludge," iron oxide includes magnetite.  Magnetite is a naturally occurring brownish-black or black material that is extremely fine and becomes a black, sticky mess inside hydronic systems.  Magnetite can get into valves and ECM motors.  It can also build up on the surfaces in a boiler or heat exchanger and act as an insulator to reduce heat transfer and system efficiency. 

**In short, iron oxide and its unfriendly cousin magnetite are extremely bad for hydronic systems.**

We can do a lot to combat both the development of iron oxide and its inevitable impact on our HVAC systems by including a few select pieces of equipment at initial system design or for retrofits when we're looking to improve system efficiency or solve system problems.

- **![air dirt separator](https://blogs.heattransfersales.com/hs-fs/hubfs/Screenshot%202019-02-06%2010.33.13.png?width=84&name=Screenshot%202019-02-06%2010.33.13.png)Air-dirt separators: ** Let's face it, everyone in the commercial building industry wants to save money without sacrificing heat transfer and efficiency.  The Taco 4900 Series Air/Dirt Separator can help design engineers and building owners prolong the life of system pumps, piping and components by removing air and dirt from the system.  The 4900 uses patented PALL rings to remove microbubbles, sand, dirt and rust.  Dirt and iron oxide particles are caught and sifted to the bottom of the tank, where they can be removed by a blowdown valve.  One example of the effectiveness of the equipment is found at the Renaissance Providence Hotel.  The hotel had air in the piping system which caused iron oxide to develop and the air conditioning system to be impacted.  Guest rooms were stuck at 75ºF dry bulb and 64º wet bulb resulting in unhappy guests and a huge problem for the hotel.  After testing the water in the system, engineers thought that at least some of the sludge in the system could be micro-biological induced corrosion (MIC).  The MIC was certainly contributing to piping corrosion.  Taco solved the problem with an air-dirt separator.   [Click here](http://www.taco-hvac.com/news.html?action=detail&newsid=450) to read Taco's case study on the hotel.
  
  [![MagStrainer filter](https://blogs.heattransfersales.com/hs-fs/hubfs/Screen%20Shot%202021-06-30%20at%204.38.22%20PM.png?width=179&name=Screen%20Shot%202021-06-30%20at%204.38.22%20PM.png)](https://www.magstrainer.com/products)**Magnetic dirt filter: ** The bigger the system, the bigger the problems can be when it comes to iron oxide and magnetite.  Using rare earth neodymium magnets, MagStrainer offers simple devices designed to solve a complex problem.  MagStrainer is not limited by size and can be placed on pipes as large as 32 inches.  MagStrainer filters are designed to fit in standard filtration housing assemblies. The advantage is you can acquire just the filter and it will work with your existing assembly. You get a tremendous upside advantage of an investment already made, with little to no system down time.
- **LPD Y-Strainers with magnets:**  Metraflex designed the [lowest pressure drop Y-strainer on the market](https://www.metraflex.com/strainers-and-suction-diffusers/lpd-m/) and then upgraded it with ![LPD Y-strainer with magnet](https://blogs.heattransfersales.com/hs-fs/hubfs/Screenshot%202019-01-22%2008.31.54.png?width=273&name=Screenshot%202019-01-22%2008.31.54.png)a neodymium magnet to catch iron oxides.  The rare-earth magnet is installed into the collection vortex of the LPD which maximizes the magnet's ability to catch iron oxide.  The blowdown port allows a thorough blowdown of the strainer to remove iron oxide while in service.

If you are a design engineer and want to learn more about how to combat iron oxide in your HVAC systems, Heat Transfer Sales offers a PDH seminar for engineers called "*Air and Dirt **DO** Hurt."  *Our training engineers come to your office in NC or SC to teach you more about how to fight air and dirt in HVAC system design to increase the longevity of the system, improve efficiency and, perhaps most important to building owners, reduce downtime.  

 

*Author's note:  This updated blog post originally appeared in February 2019. *

 

 

###### About The Author

[More from this author](https://blogs.heattransfersales.com/blog/author/kelly-patterson)

![](https://blogs.heattransfersales.com/hs-fs/hubfs/Blog_images/10801587_10152577444568382_8583161712827376882_n.jpg?height=100&name=10801587_10152577444568382_8583161712827376882_n.jpg)

###### Kelly Patterson

 Kelly Patterson is an avid fan of marketing HVAC and plumbing equipment and does it on a daily basis for all the Hoffman family of companies.

<https://www.facebook.com/kelly.tilyard> <https://www.linkedin.com/in/kellytilyard> <https://blogs.heattransfersales.com/blog/KPatterson@heattransfersales.com>

#### Recommended Articles

[![4 Benefits of Switching to a Hydronic HVAC System](https://blogs.heattransfersales.com/hubfs/h4qhtnb3.png)](https://blogs.heattransfersales.com/blog/4-benefits-of-switching-to-a-hydronic-hvac-system)

###### [4 Benefits of Switching to a Hydronic HVAC System](https://blogs.heattransfersales.com/blog/4-benefits-of-switching-to-a-hydronic-hvac-system)

 - December 6, 2022

[![Troubleshooting Mechanical Room Noises](https://blogs.heattransfersales.com/hubfs/ergdfb.png)](https://blogs.heattransfersales.com/blog/troubleshooting-mechanical-room-noises)

###### [Troubleshooting Mechanical Room Noises](https://blogs.heattransfersales.com/blog/troubleshooting-mechanical-room-noises)

 - August 19, 2022

#### Recommended Articles

#### Recommended Articles

#### Recommended Articles

#### Recommended Articles

Search Article

### Popular Posts

### Stay up to date

### Recent Post

### Recent Posts

[A Look at Why the Riello Array Has Won So Many Awards](https://blogs.heattransfersales.com/blog/a-look-at-why-the-riello-array-has-won-so-many-awards)

 - 30 June, 2021

[Replacing Outdated Boilers to Meet New DOE Standards](https://blogs.heattransfersales.com/blog/replacing-outdated-boilers-to-meet-new-doe-standards)

 - 30 June, 2021

[3 “NEED TO KNOWS” ABOUT DHW SYSTEMS](https://blogs.heattransfersales.com/blog/3-need-to-knows-about-dhw-systems)

 - 30 June, 2021

[4 Benefits of Switching to a Hydronic HVAC System](https://blogs.heattransfersales.com/blog/4-benefits-of-switching-to-a-hydronic-hvac-system)

 - 30 June, 2021

[Why Prefabricated Pumping Systems Ease System Design](https://blogs.heattransfersales.com/blog/why-prefabricated-pumping-systems-ease-system-design)

 - 30 June, 2021

###### ABOUT THE COMPANY

![HTS_Symbol_RGB](https://blogs.heattransfersales.com/hubfs/HTS_Symbol_RGB.png)

### Heat Transfer Sales, LLC

We are proponents of sustainable and efficient hydronic heating and cooling building solutions, which are at the heart of commercial green building.

- <https://www.facebook.com/Heat-Transfer-Sales-of-the-Carolinas-1656743191224178/timeline/>
- <https://www.linkedin.com/company/heat-transfer-sales-of-the-carolinas-inc>
- <https://twitter.com/htscarolinas>
- <https://www.youtube.com/channel/UCX51QZbsuqCtu2PxtW9jMEg>

### Topics

- [Design Engineer Tips (109)](https://blogs.heattransfersales.com/blog/topic/design-engineer-tips)
- [General Knowledge (95)](https://blogs.heattransfersales.com/blog/topic/general-knowledge)
- [Building Owner Tips (70)](https://blogs.heattransfersales.com/blog/topic/building-owner-tips)
- [Pumps (56)](https://blogs.heattransfersales.com/blog/topic/pumps)
- [Manufacturer Information (46)](https://blogs.heattransfersales.com/blog/topic/manufacturer-information)
- [Boilers and Water Heaters (40)](https://blogs.heattransfersales.com/blog/topic/boilers-and-water-heaters)
- [Efficiency (22)](https://blogs.heattransfersales.com/blog/topic/efficiency)
- [Training (22)](https://blogs.heattransfersales.com/blog/topic/training)
- [Webinars (18)](https://blogs.heattransfersales.com/blog/topic/webinars)
- [Customer Service (17)](https://blogs.heattransfersales.com/blog/topic/customer-service)
- [Energy Savings (14)](https://blogs.heattransfersales.com/blog/topic/energy-savings)
- [Air Curtains (13)](https://blogs.heattransfersales.com/blog/topic/air-curtains)
- [HVAC (12)](https://blogs.heattransfersales.com/blog/topic/hvac)
- [Metraflex (12)](https://blogs.heattransfersales.com/blog/topic/metraflex)
- [infrared Heating (12)](https://blogs.heattransfersales.com/blog/topic/infrared-heating)
- [Products (10)](https://blogs.heattransfersales.com/blog/topic/products)
- [HVAC Design Tools (9)](https://blogs.heattransfersales.com/blog/topic/hvac-design-tools)
- [PDH Credits (9)](https://blogs.heattransfersales.com/blog/topic/pdh-credits)
- [Parts (9)](https://blogs.heattransfersales.com/blog/topic/parts)
- [Hydronic (8)](https://blogs.heattransfersales.com/blog/topic/hydronic)
- [Filtration (7)](https://blogs.heattransfersales.com/blog/topic/filtration)
- [Boilers (6)](https://blogs.heattransfersales.com/blog/topic/boilers)
- [Taco (6)](https://blogs.heattransfersales.com/blog/topic/taco)
- [Piping (4)](https://blogs.heattransfersales.com/blog/topic/piping)
- [Raypak (4)](https://blogs.heattransfersales.com/blog/topic/raypak)
- [Schwank (4)](https://blogs.heattransfersales.com/blog/topic/schwank)
- [Valves (4)](https://blogs.heattransfersales.com/blog/topic/valves)
- [Variable Frequency Drives (4)](https://blogs.heattransfersales.com/blog/topic/variable-frequency-drives)
- [Water (4)](https://blogs.heattransfersales.com/blog/topic/water)
- [Water Purification (4)](https://blogs.heattransfersales.com/blog/topic/water-purification)
- [Burners (3)](https://blogs.heattransfersales.com/blog/topic/burners)
- [Commercial Boiler (3)](https://blogs.heattransfersales.com/blog/topic/commercial-boiler)
- [Cooling Towers (3)](https://blogs.heattransfersales.com/blog/topic/cooling-towers)
- [Green Building Design and Equipment (3)](https://blogs.heattransfersales.com/blog/topic/green-building-design-and-equipment)
- [Pump'nFlo (3)](https://blogs.heattransfersales.com/blog/topic/pumpnflo)
- [Riello (3)](https://blogs.heattransfersales.com/blog/topic/riello)
- [About us (2)](https://blogs.heattransfersales.com/blog/topic/about-us)
- [Expansion Joints (2)](https://blogs.heattransfersales.com/blog/topic/expansion-joints)
- [Outdoor Dining (2)](https://blogs.heattransfersales.com/blog/topic/outdoor-dining)
- [Pump Selection (2)](https://blogs.heattransfersales.com/blog/topic/pump-selection)
- [Technician Tips (2)](https://blogs.heattransfersales.com/blog/topic/technician-tips)
- [humidification (2)](https://blogs.heattransfersales.com/blog/topic/humidification)
- [pure humidifier (2)](https://blogs.heattransfersales.com/blog/topic/pure-humidifier)
- [AERCO (1)](https://blogs.heattransfersales.com/blog/topic/aerco)
- [Air Release Valve (1)](https://blogs.heattransfersales.com/blog/topic/air-release-valve)
- [Anchor Load Calculations (1)](https://blogs.heattransfersales.com/blog/topic/anchor-load-calculations)
- [Chillers (1)](https://blogs.heattransfersales.com/blog/topic/chillers)
- [Closed-Coupled Design (1)](https://blogs.heattransfersales.com/blog/topic/closed-coupled-design)
- [Commercial HVAC (1)](https://blogs.heattransfersales.com/blog/topic/commercial-hvac)
- [Commercial Range (1)](https://blogs.heattransfersales.com/blog/topic/commercial-range)
- [Compensator (1)](https://blogs.heattransfersales.com/blog/topic/compensator)
- [Cooling (1)](https://blogs.heattransfersales.com/blog/topic/cooling)
- [Delegated Design (1)](https://blogs.heattransfersales.com/blog/topic/delegated-design)
- [Digital Gas Heater (1)](https://blogs.heattransfersales.com/blog/topic/digital-gas-heater)
- [Expansion Tanks (1)](https://blogs.heattransfersales.com/blog/topic/expansion-tanks)
- [Externally Pressurized Joint (1)](https://blogs.heattransfersales.com/blog/topic/externally-pressurized-joint)
- [Guide Spacing Requirements (1)](https://blogs.heattransfersales.com/blog/topic/guide-spacing-requirements)
- [Heaters (1)](https://blogs.heattransfersales.com/blog/topic/heaters)
- [Hospitals (1)](https://blogs.heattransfersales.com/blog/topic/hospitals)
- [LEED (1)](https://blogs.heattransfersales.com/blog/topic/leed)
- [LPD Strainer (1)](https://blogs.heattransfersales.com/blog/topic/lpd-strainer)
- [Make-up Water (1)](https://blogs.heattransfersales.com/blog/topic/make-up-water)
- [Metal Expansion Joints (1)](https://blogs.heattransfersales.com/blog/topic/metal-expansion-joints)
- [MetraPak (1)](https://blogs.heattransfersales.com/blog/topic/metrapak)
- [Metraloop (1)](https://blogs.heattransfersales.com/blog/topic/metraloop)
- [New Product (1)](https://blogs.heattransfersales.com/blog/topic/new-product)
- [PAX Series (1)](https://blogs.heattransfersales.com/blog/topic/pax-series)
- [Pipe Penetration Seal (1)](https://blogs.heattransfersales.com/blog/topic/pipe-penetration-seal)
- [Potable Water Systems (1)](https://blogs.heattransfersales.com/blog/topic/potable-water-systems)
- [Project Files (1)](https://blogs.heattransfersales.com/blog/topic/project-files)
- [Pump collector (1)](https://blogs.heattransfersales.com/blog/topic/pump-collector)
- [Quiz (1)](https://blogs.heattransfersales.com/blog/topic/quiz)
- [Refrigerant (1)](https://blogs.heattransfersales.com/blog/topic/refrigerant)
- [Restaurant Patios (1)](https://blogs.heattransfersales.com/blog/topic/restaurant-patios)
- [Riser Anchor Clamp (1)](https://blogs.heattransfersales.com/blog/topic/riser-anchor-clamp)
- [SST Series (1)](https://blogs.heattransfersales.com/blog/topic/sst-series)
- [Steam (1)](https://blogs.heattransfersales.com/blog/topic/steam)
- [SuctionDiffuserFlex (1)](https://blogs.heattransfersales.com/blog/topic/suctiondiffuserflex)
- [System Feed Units (1)](https://blogs.heattransfersales.com/blog/topic/system-feed-units)
- [VRF (1)](https://blogs.heattransfersales.com/blog/topic/vrf)
- [VaneFlex (1)](https://blogs.heattransfersales.com/blog/topic/vaneflex)
- [Vertical Inline (1)](https://blogs.heattransfersales.com/blog/topic/vertical-inline)
- [Y-Strainer (1)](https://blogs.heattransfersales.com/blog/topic/y-strainer)
- [YANMAR (1)](https://blogs.heattransfersales.com/blog/topic/yanmar)
- [seismic breakaway hanger (1)](https://blogs.heattransfersales.com/blog/topic/seismic-breakaway-hanger)
- [superTube (1)](https://blogs.heattransfersales.com/blog/topic/supertube)

see all

[![New Call-to-action](https://no-cache.hubspot.com/cta/default/715354/d9a35e17-d3c8-44b5-91e0-47a3bcfea5f0.png)](https://cta-redirect.hubspot.com/cta/redirect/715354/d9a35e17-d3c8-44b5-91e0-47a3bcfea5f0)

#### Submit a Comment

### Get latest articles directly in your inbox, stay up to date

 SUBSCRIBE TO OUR BLOG

**Our Location**

Headquarters  
4101 Beechwood Drive,  
Greensboro, NC 27410

[Get Directions](https://www.google.com/maps/place/4101+Beechwood+Dr,+Greensboro,+NC+27410/@36.0544034,-79.9484879,17z/data=!3m1!4b1!4m5!3m4!1s0x8853051e63c99b6d:0x24b2c5a3927d7634!8m2!3d36.0544034!4d-79.9462992)

**Contact Us**

336.294.3838  
[info@heattransfersales.com](mailto:info@heattransfersales.com)

[![Untitled design - 2020-11-19T112748.776](https://blogs.heattransfersales.com/hs-fs/hubfs/Untitled%20design%20-%202020-11-19T112748.776.png?width=24&name=Untitled%20design%20-%202020-11-19T112748.776.png)](https://www.linkedin.com/company/heat-transfer-sales-of-the-carolinas-inc)  
[![Untitled design - 2020-11-19T112815.271](https://blogs.heattransfersales.com/hs-fs/hubfs/Untitled%20design%20-%202020-11-19T112815.271.png?width=24&name=Untitled%20design%20-%202020-11-19T112815.271.png)](https://www.facebook.com/HeatTransferSales/)  
[![Untitled design - 2020-11-19T112835.473](https://blogs.heattransfersales.com/hs-fs/hubfs/Untitled%20design%20-%202020-11-19T112835.473.png?width=24&name=Untitled%20design%20-%202020-11-19T112835.473.png)](https://twitter.com/htscarolinas)  
[![Untitled design - 2020-11-19T112859.003](https://blogs.heattransfersales.com/hs-fs/hubfs/Untitled%20design%20-%202020-11-19T112859.003.png?width=24&name=Untitled%20design%20-%202020-11-19T112859.003.png)](https://www.youtube.com/channel/UCX51QZbsuqCtu2PxtW9jMEg)

- [Home](https://heattransfersales.com/)
- [Products](https://heattransfersales.com/products) 
    - [Manufacturers Represented](https://heattransfersales.com/products)
    - [Packaged Systems](https://heattransfersales.com/products)
- [Customer Service](https://heattransfersales.com/customer-service) 
    - [Parts](https://heattransfersales.com/parts)
    - [Pump Repair](https://heattransfersales.com/pump-repair)
    - [Service](https://heattransfersales.com/service)
- [Pump'nFlo](https://heattransfersales.com/pump-nflo)
- [Resources](https://heattransfersales.com/resources) 
    - [Training](https://heattransfersales.com/training)
    - [Sustainable System Concepts](https://heattransfersales.com/sustainable-system-concepts)
    - [Airside HVAC](https://heattransfersales.com/hvac-equipment)
    - [Plumbing Equipment](https://heattransfersales.com/plumbing-equipment)
    - [Building Automation](https://heattransfersales.com/building-automation)
    - [Blog](https://blogs.heattransfersales.com/blog)
- [Careers](https://heattransfersales.com/careers)
- [About Us](https://heattransfersales.com/about-us) 
    - [History](https://heattransfersales.com/history)
    - [Privacy Policy](https://324b4bc7-5729-4ace-b8c0-bc77b425b76e.filesusr.com/ugd/ff46b9_f6100e8b535d465f9fb060f60f8049cc.pdf)
    - [Terms of Use](https://324b4bc7-5729-4ace-b8c0-bc77b425b76e.filesusr.com/ugd/ff46b9_8a108a4c73734c8ca00866bdecf7cb60.pdf)
- [Contact](https://heattransfersales.com/contact)

![HTS_Logo_Symbol_White_CMYK](https://blogs.heattransfersales.com/hs-fs/hubfs/HTS_Logo_Symbol_White_CMYK.png?width=52&height=52&name=HTS_Logo_Symbol_White_CMYK.png "HTS_Logo_Symbol_White_CMYK")

All content © 2020, Heat Transfer Sales