Home Inspection and the Hot Water Heater a Life Safety Issue

The water heater, a home inspection life safety issue

Home inspection in Gravenhurst, Bracebridge and Orillia can be very interesting due to the wide variety of structures and home styles. I inspect Log homes to ultra modern concrete and glass homes and everything in between. When it comes to inspecting cottages throughout Muskoka they run the gamut  from 200 sq ft thrown up basic shelters to very large multi structure estate homes.  While the basic premise behind home inspections is providing the client with peace of mind in the decision making process with information on any material defects in the home there are safety issues that come up as well. Most safety issues , like the rest of the report are confidential to the client. It is the client’s home inspection, they pay for the report and only they have the right to its contents. On occasion a life safety issue emerges during the inspection and that type of issue I inform my clients I would report to the sellers Real Estate agent or have the clients agent report it to them. One such safety issue I come across all too often in my home and cottage inspections is the incorrect installation of the hot water heater.

Most homeowners and handy men are not aware of what and how a Temperature pressure relief valve is or does. I must confess that despite having installed many electric hot water heaters myself according to manufactures directions ( yep I am apparently one of the few guys who reads them all. ) I too was unaware of the deadly potential these items have in the home. Until I undertook my home inspection training through Carson Dunlop Engineering  Home Inspection Program I viewed hot water heaters as a simple device pretty much anyone could install safely.  That viewpoint changed as I came to understand the relationship between the sudden release of steam energy, and the role the Temperature Pressure Release Valve on the hot water heater plays in preventing the buildup of steam energy in the first place.  

 Here I am going to do something unusual for a blog article

This is a site I would like you to visit before going on,  it is a video from the television series Mythbusters and it illustrates the explosive power of the hot water tank. In the video they have removed the safety mechanisms to force the result for the show but failure of the secondary safety or a lack of it could and has produced the same result in homes. After you visit and view the video come back and I will tell you about the safety mechanisms and what I find that is a life safety issue when inspecting homes and cottages.

http://www.youtube.com/watch?feature=player_detailpage&v=jbreKn4PoAc

Back again, pretty impressive video wasn’t it. 

The hot water heater safety mechanisms

Whether gas, oil, or electric, and apart from the safety features found on the fuel and exhaust systems all domestic hot water heaters share having a control mechanism for the elements or burner that regulates the water temperature. Basically this is a fairly simple thermostat that shuts off the burner or element when the water gets to a set temperature. All of these primary safety controls share two things in common, the first is they are designed to shut off at an upper limit no matter what the set desired temperature is. In other words if the set desired temperature is exceeded and the burner or element continues to run then well below boiling the designed limit is reached and the burner or element shuts down. The second thing they share in common is they fail, often. For a variety of reasons they fail, the most common reason being rusting in humid conditions, but dust and debris and inexpert fooling with the setting mechanism itself can also cause failure. There is no problem if they fail in the off position which is usually the case. You just lose your hot shower, inconvenient, but hardly life threatening.  However, if the element safety fails in the on position the water heater would, without the second safety, become a steam boiler. This why the need for the second safety required on a water heater as from the video you already know what happens when steam energy suddenly lets go.

So what stops the water heater from going through the roof?

The secondary and most important safety on the water heater: the temperature pressure release valve is supposed to eliminate the possibility of water heater explosion. This valve, commonly installed on the side of the tank or on top, is designed to open under pressure ( the hotter the water gets close to boiling the higher the pressure. ) It simply is a spring with a stopper and as the pressure rises in the tank the spring pressure closing the stopper is overcome releasing pressure and water before it can turn to steam.

Here you see the Temperature pressure release valve on the side of the tank with the proper ¾ , inch (2cm) line extending to within one foot (25 cm) of the floor

Here you see a temperature pressure relief top install on a water heater

 Why is the incorrect installation of the water heater a life safety issue?

Simply put without the secondary temperature pressure relief valve in place the water heater could and has destroyed homes.

 Do I find water heaters without these safety valves installed really?

Here are a few photos of water heaters in homes I have inspected in the Muskoka Bracebridge and Gravenhurst areas.

In the first picture it was difficult to get the photo due to space restrictions but you can make out the label instructs the installer to Install relief valve here. Just below label

Here is the photo of what was installed.

The Real Estate agent told my client in hundreds of sales he had done with home inspections he had never heard of such a thing as an explosive hot water heater.

Here is another water heater missing the TPR valve. I had to look very carefully as it might have been installed on the back but no there was no side mount  TPR nor as you can see was there a top mount TPR which would have been the first valve out of the hot water line right at the top of the tank. I had to crawl on top to see behind this one.

Both these improperly installed waters were from 2012 inspections.

The Home seller needs to know

Some manufacturers supply heaters with the TPR valve installed but many come without. The ones that do have the valve installed often come without the extension directed to the floor which I find as well during my home inspections.  As a home owner or buyer you should check to see that there is a TPR valve and it is correctly installed is on the water heater in your home. It is a life safety issue.  One of the few issues that as a home inspector in the Bracebridge, Muskoka, Gravenhurst and Orillia areas I will request be divulged to the sellers either directly or through their agent.