Gas Tankless Water Heater-best Locations For Installation
This is a long article but it goes in-depth about planning the location of your gas or propane heater. The first thing to do is forget about the location of your old tank system and think about where you would install the system if it was a brand new house without any water heater installed. This is the mindset you will need to properly evaluate the best location for installing your system.
The Basic Installation
The basic gas heater installation requires the properly sized tankless water heater, venting components, extension of the hot and cold piping, an electrical connection and a gas connection. The size of the heater can be determined based on how many fixtures you are connecting to the heater but is not covered in this article. The venting components include the combustion air intake and exhaust flue, sometimes called the intake and exhaust piping. The electrical connection is typically for the on-board controls and spark to light the gas. The gas connection is the piping that connects to your existing gas service, which will be extended to your heater. These are the typical components and each one needs to be considered before selecting the best location for your heater.
Venting Discussion
Direct vent heaters are the recommended types of heaters to install. Some have a fan to assist in the combustion process and some don't. The reason for direct vent types is based on building code requirements. Most, if not all codes require that gas burning equipment be installed where they have enough air to "breathe". For every BTU input of gas to the heater, there needs to be enough air in the room to assure that the combustion chamber of the heater breathes freely. Simply put, the bigger the heater, the bigger the room has to be to avoid "starving" the combustion chamber. This requirement determines if the room is to be considered a "confined space" or not. When you do the calculation for a non-direct vent heater, most spaces are considered as a confined space and this probably includes your garage. If your building inspector finds a non-direct vent heater installed in a confined space, you will probably be told to add 2 new penetrations through the wall (known as high-and-low venting) or you will be told to remove it until it conforms to the code requirements.
For those interested in the exact code terminology here you go; UNCONFINED SPACE- A space having a volume not less than 50 cubic feet per 1,000 Btu/h of the aggregate input rating of all appliances installed in that space. Rooms communicating directly with the space in which the appliances are installed, through openings not furnished with doors, are considered a part of the unconfined space.
Take a look at your current gas heater and notice the vent hood which is slightly above the top of the heater. This is normally a 3 or 4 inch diameter stainless steel vent the collects the products of combustion and funnels them to the exterior. It is a direct route to the exterior from the heater and works on the "hot air rises" principle which means that the hot combustion gases from the heater rise up, get captured by the draft hood and are lead to the exterior. Because it is a direct route, air in the space also gets lead to the exterior when the gas heater is not working. Therefore, regardless of the efficiency rating of your tankless heater, if it is not a direct-vent model, your home will lose heat (and air conditioning) to any tankless model that uses room air for combustion.
To avoid throwing away any air in your house or business and installing it in an "enclosed area", direct vent models are recommended because they get combustion air from the exterior of your home or office and route the products of combustion to the exterior as well. They do not use inside air for combustion which probably is already conditioned by your heating and air conditioning system.
Minimize The Expenses
Other than the cost of the heater, the most expensive part of the installation is the intake and exhaust piping. When considering an optimized location for your gas heater, consider an exterior wall that is close to your plumbing fixtures. This will minimize your venting costs and the time it takes the hot water to get to your fixture (known as "lag"). Your first instinct may be to install the tankless heater in the same location as the old tank type heater. Resist this thought. Can you use the space more efficiently if the water heater was not there?
The second biggest expense is the extension of your gas piping. Normally there are not many runs of gas piping in your residence or business due to the cost of materials and installation. Consider a location where the gas piping is relatively close and easy to extend. The piping size will be determined by the size of the heater but if you can connect to a 3/4 inch piece of pipe, you are probably ok.
Running a close third in expenses is the cost of extending the hot and cold piping. This is about the same cost as running the new gas line so I won't repeat what is discussed above. All I will say is that this should not stop you from evaluating your installation location.
The last expense is the electrical circuit. The electrical connection is typically for the on-board controls and spark to light the gas. The amount of electricity required for a gas heater is very small. In most situations, the electrician can connect to an existing circuit that is powering your wall receptacles or something similar. Even if it is a longer run to a better connection point, the expense is not that great and should not stop you from optimizing your installation location.
Don't Let a Little Bit Education Stop You
The installation of a tankless system is a step forward in technology and greener, more efficient living. This is a major change to most American households and many people have not embraced this technology because it is so new. Consider educating yourself more about these systems because they will soon dominate the water heater industry. It is human nature to be reluctant to change old habits, but a bit of education and preparation is all you need to break from tradition. You may hear negative comments from people, even from some plumbers. The negative comments may simply be due to inexperience or lack of education about these systems. More and more plumbers are recognizing this as an opportunity and immediately jumping on board.
Educate, Prepare and then Act!
The Basic Installation
The basic gas heater installation requires the properly sized tankless water heater, venting components, extension of the hot and cold piping, an electrical connection and a gas connection. The size of the heater can be determined based on how many fixtures you are connecting to the heater but is not covered in this article. The venting components include the combustion air intake and exhaust flue, sometimes called the intake and exhaust piping. The electrical connection is typically for the on-board controls and spark to light the gas. The gas connection is the piping that connects to your existing gas service, which will be extended to your heater. These are the typical components and each one needs to be considered before selecting the best location for your heater.
Venting Discussion
Direct vent heaters are the recommended types of heaters to install. Some have a fan to assist in the combustion process and some don't. The reason for direct vent types is based on building code requirements. Most, if not all codes require that gas burning equipment be installed where they have enough air to "breathe". For every BTU input of gas to the heater, there needs to be enough air in the room to assure that the combustion chamber of the heater breathes freely. Simply put, the bigger the heater, the bigger the room has to be to avoid "starving" the combustion chamber. This requirement determines if the room is to be considered a "confined space" or not. When you do the calculation for a non-direct vent heater, most spaces are considered as a confined space and this probably includes your garage. If your building inspector finds a non-direct vent heater installed in a confined space, you will probably be told to add 2 new penetrations through the wall (known as high-and-low venting) or you will be told to remove it until it conforms to the code requirements.
For those interested in the exact code terminology here you go; UNCONFINED SPACE- A space having a volume not less than 50 cubic feet per 1,000 Btu/h of the aggregate input rating of all appliances installed in that space. Rooms communicating directly with the space in which the appliances are installed, through openings not furnished with doors, are considered a part of the unconfined space.
Take a look at your current gas heater and notice the vent hood which is slightly above the top of the heater. This is normally a 3 or 4 inch diameter stainless steel vent the collects the products of combustion and funnels them to the exterior. It is a direct route to the exterior from the heater and works on the "hot air rises" principle which means that the hot combustion gases from the heater rise up, get captured by the draft hood and are lead to the exterior. Because it is a direct route, air in the space also gets lead to the exterior when the gas heater is not working. Therefore, regardless of the efficiency rating of your tankless heater, if it is not a direct-vent model, your home will lose heat (and air conditioning) to any tankless model that uses room air for combustion.
To avoid throwing away any air in your house or business and installing it in an "enclosed area", direct vent models are recommended because they get combustion air from the exterior of your home or office and route the products of combustion to the exterior as well. They do not use inside air for combustion which probably is already conditioned by your heating and air conditioning system.
Minimize The Expenses
Other than the cost of the heater, the most expensive part of the installation is the intake and exhaust piping. When considering an optimized location for your gas heater, consider an exterior wall that is close to your plumbing fixtures. This will minimize your venting costs and the time it takes the hot water to get to your fixture (known as "lag"). Your first instinct may be to install the tankless heater in the same location as the old tank type heater. Resist this thought. Can you use the space more efficiently if the water heater was not there?
The second biggest expense is the extension of your gas piping. Normally there are not many runs of gas piping in your residence or business due to the cost of materials and installation. Consider a location where the gas piping is relatively close and easy to extend. The piping size will be determined by the size of the heater but if you can connect to a 3/4 inch piece of pipe, you are probably ok.
Running a close third in expenses is the cost of extending the hot and cold piping. This is about the same cost as running the new gas line so I won't repeat what is discussed above. All I will say is that this should not stop you from evaluating your installation location.
The last expense is the electrical circuit. The electrical connection is typically for the on-board controls and spark to light the gas. The amount of electricity required for a gas heater is very small. In most situations, the electrician can connect to an existing circuit that is powering your wall receptacles or something similar. Even if it is a longer run to a better connection point, the expense is not that great and should not stop you from optimizing your installation location.
Don't Let a Little Bit Education Stop You
The installation of a tankless system is a step forward in technology and greener, more efficient living. This is a major change to most American households and many people have not embraced this technology because it is so new. Consider educating yourself more about these systems because they will soon dominate the water heater industry. It is human nature to be reluctant to change old habits, but a bit of education and preparation is all you need to break from tradition. You may hear negative comments from people, even from some plumbers. The negative comments may simply be due to inexperience or lack of education about these systems. More and more plumbers are recognizing this as an opportunity and immediately jumping on board.
Educate, Prepare and then Act!
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