Water heaters not ideal for room heat
Re: Gas water heaters an ideal solution for Canadian space heating, March 6.
The Canadian Institute of Plumbing and Heating takes issue with this article. CIPH is a not-for-profit trade association representing more than 283 companies that manufacture and distribute plumbing, heating, hydronic, industrial PVF, and waterworks, and other mechanical products.
The article is promoting the use of water heaters for combined space and water heating applications; however, we believe author Steve Maxwell oversimplifies the design and installation requirements for these types of systems, and fails to mention any of the plumbing and heating code requirements, or any of the negative issues that can occur.
Maxwell says that you can “tap into an existing water heater” for space heating, but this is not the case for the vast majority of homes.
The National Building Code and Ontario Building Code have specific requirements for installation of dual-purpose water heating equipment. Installations must be done in accordance with CSA Standard B214-16, which is the installation code for hydronic heating systems.
This code specifies that any water heater used for combined space- and waterheating applications must be certified for dual use to standards ANSI Z21.10.3/CSA 4.3; or CSA B140.10.
The code also has very specific sizing requirements for dual-purpose water heating equipment, otherwise the customer will be left with either not enough hot water, not enough space heating capacity, or both.
Maxwell also says a “boiler is not essential for space heating applications” and for using a water heater “for bigger homes or older places that are less efficient.”
We believe these statements could lead homeowners to make terrible decisions for their heating systems.
Modern heating boilers are the best choice for the vast majority of hydronic space heating systems, and should always be used for bigger homes or older places that are less efficient.
They are compact, silent, durable and long lasting, fully modulating and have efficiency ratings up to 98 per cent. This is the reason plenty of heating contractors tell their customers that they need a boiler, not a water heater.
It is true that certain certified dual-purpose water heaters, when sized and installed properly, can be an effective method of addressing some hydronic heating loads.
But homeowners should always consult a reputable and certified mechanical contractor when making heating appliance choices for their homes.
The type of system that Maxwell installs in his own house “in the backwoods of Manitoulin Island” is one thing, but we believe that what most people should install in their own homes in other jurisdictions is quite different.
Robert Waters, technical consultant, codes and standards, Canadian Institute of Plumbing and Heating, Etobicoke