--- title: 3 Benefits of a Combined Space & Water Heating Plant description: Conventional thought has always been to design a boiler system to handle heating and a separate water heating system to satisfy hot water demands. image: https://blogs.heattransfersales.com/hubfs/Blog_images/Screen_Shot_2016-04-26_at_8.56.14_AM.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) [Products](https://blogs.heattransfersales.com/blog/topic/products) [Boilers and Water Heaters](https://blogs.heattransfersales.com/blog/topic/boilers-and-water-heaters) [Design Engineer Tips](https://blogs.heattransfersales.com/blog/topic/design-engineer-tips) # 3 Benefits of a Combined Space & Water Heating Plant ![Picture of Joe Britt, PE](https://blogs.heattransfersales.com/hubfs/Blog_images/Joe_Britt_blog_avatar.jpg) By [Joe Britt, PE](https://blogs.heattransfersales.com/blog/author/joe-britt-pe) on May, 12 2016 [mailto:?body=https://blogs.heattransfersales.com/blog/3-benefits-of-a-combined-space-water-heating-plant](mailto:?body=https://blogs.heattransfersales.com/blog/3-benefits-of-a-combined-space-water-heating-plant) ![](https://blogs.heattransfersales.com/hubfs/Blog_images/Screen_Shot_2016-04-26_at_8.56.14_AM.png) For most commercial and institutional buildings, conventional thought has always been to design a boiler system to handle heating loads and a separate water heating system to satisfy domestic hot water demands.  This is a relatively simple, straightforward approach.  However, did you know there are some big benefits to consider when putting the domestic hot water heating load onto the space heating boilers?  Consider these three benefits to using condensing gas-fired space heating boilers with a plate and frame heat exchanger (P&F HX) for domestic water heating: 1. **Total required heating capacity Is reduced.**  By combining the space heating and domestic water heating loads onto the same equipment, the overall capacity may be reduced.  See the graph below from the ASHRAE HVAC Applications Handbook and the example numbers in red.   ![Screen_Shot_2016-04-26_at_8.56.14_AM.jpg](https://blogs.heattransfersales.com/hubfs/Blog_images/Screen_Shot_2016-04-26_at_8.56.14_AM.jpg "Screen_Shot_2016-04-26_at_8.56.14_AM.jpg")      **This is possible because of the following *(ref: ASHRAE HVAC Applications Handbook Chapter 50)*:** a.    **Maximum space-heating requirements** do not occur at the time of day when the maximum peak hot-water demands occur. b.    Space-heating requirements are based on the **lowest outdoor design temperature**, which may occur for only a few days of the total heating season. c.     An additional heat supply or boiler capacity to compensate for pickup and radiation losses is usual.  **The pickup load cannot occur at the same time as the peak hot-water demand** because the building must be brought to a comfortable temperature before the occupants use hot water. 2. **Boiler plant efficiency may be increased.**  For condensing boilers, the lower the return water temperature, the higher the efficiency.  The <60°F domestic cold water entering the P&F HX will help lower the temperature of the building return water even more before it enters the boilers, resulting in greater combustion efficiency. 3. **No storage. ** If you are serving a laundry system, a large kitchen, or other application with large hot water dump loads, this does not apply.  For most other standard commercial or institutional buildings, removing hot water storage tanks and replacing them with a P&F HX is beneficial because: a.    **Storage tanks eventually leak. ** Some lining material lasts longer than others, but, at some point, the water chemistry will win the day and that storage tank will need to be replaced.  This may be costly and impractical due to the installation location. b.    **Storage-type water heaters fail quicker than storage tanks. ** When you have the fire inside the storage vessel, you are exposing dissimilar materials to variations in temperature.  With different rates of expansion, the materials and their bonds eventually fail. c.     **Prevents stagnation and *Legionella* growth. ** Water maintained at certain temperatures within a storage tank or storage heater can create an environment favorable for the growth of the bacteria *Legionella*.  By eliminating storage, this risk is greatly reduced. There are products and technologies that make this heating approach much simpler and more advantageous than in years passed.  As always, this method may not be appropriate for every application.  If you would like to know if this combined space heating and domestic water heating strategy is right for your next project, [contact your local manufacturer's representative](https://heattransfersales.com/contact-us/). [![VRF Systems](https://no-cache.hubspot.com/cta/default/715354/9b557c10-273e-45fe-a5de-ee49593489e9.png)](https://cta-redirect.hubspot.com/cta/redirect/715354/9b557c10-273e-45fe-a5de-ee49593489e9)   ###### About The Author [More from this author](https://blogs.heattransfersales.com/blog/author/joe-britt-pe) ![](https://blogs.heattransfersales.com/hs-fs/hubfs/Blog_images/Joe_Britt_blog_avatar.jpg?height=100&name=Joe_Britt_blog_avatar.jpg) ###### Joe Britt, PE Joe Britt, PE is the President of Heat Transfer Sales and interested in educating everyone about hydronic systems. #### 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 [![Removing Iron Oxide in Hydronic HVAC Systems](https://blogs.heattransfersales.com/hubfs/Screenshot%202019-02-06%2010.46.26.png)](https://blogs.heattransfersales.com/blog/how-to-combat-iron-oxide-in-hydronic-hvac-systems-0) ###### [Removing Iron Oxide in Hydronic HVAC Systems](https://blogs.heattransfersales.com/blog/how-to-combat-iron-oxide-in-hydronic-hvac-systems-0) - June 30, 2021 #### 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) - 12 May, 2016 [Replacing Outdated Boilers to Meet New DOE Standards](https://blogs.heattransfersales.com/blog/replacing-outdated-boilers-to-meet-new-doe-standards) - 12 May, 2016 [3 “NEED TO KNOWS” ABOUT DHW SYSTEMS](https://blogs.heattransfersales.com/blog/3-need-to-knows-about-dhw-systems) - 12 May, 2016 [4 Benefits of Switching to a Hydronic HVAC System](https://blogs.heattransfersales.com/blog/4-benefits-of-switching-to-a-hydronic-hvac-system) - 12 May, 2016 [Why Prefabricated Pumping Systems Ease System Design](https://blogs.heattransfersales.com/blog/why-prefabricated-pumping-systems-ease-system-design) - 12 May, 2016 ###### 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. - - - - ### 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