Do tankless water heaters need dedicated gas line?

In many cases, there's no need to run gas line all the way around your home to reach a tankless water heater. By installing the tankless unit on an exterior wall or even outside, builders can allow for shorter gas line runs and easier venting.

Can a tankless water heater share a gas line?

Tankless heaters require a certain type of gas line

When a home has a gas dryer, a gas furnace, and a gas range, the tankless water heater will have to 'share' the gas with them, and the smaller line will come up short. A larger gas line, or high-pressure gas line, will solve this problem.

How much gas pressure does a tankless water heater need?

15-150 psi water pressure. 40 psi or above recommended for maximum flow. *For Propane, minimum inlet gas pressure is 8.0 in.

How close can a gas regulator be to a tankless water heater?

You can use a 1/2 in regulator down to 7" up to about 15 feet before the tankless. And reduce at the unit. Also check the tankless for acceptable input pressure, you may not need a reg but most likely you will.

Tankless Water Heaters: Basic Requirements for a Safe and Effective Installation

Does a tankless water heater need a pressure regulator?

Gas-fired tankless water heaters will usually require a pressure relief valve, while electric on-demand water heaters may not. The manufacturers typically only require a pressure relief valve, not the combination temperature and pressure relief valve that is necessary for tank-type water heaters.

Will a tankless water heater work with a 1/2 gas line?

Check the gas supply

A typical tankless water heater will need a ¾-inch gas line. However, if there is sufficient pressure and the run length is short enough, a ½-inch line may be sufficient with certain tankless water heaters, such as the Noritz EZ Series.

Can a gas line be too big?

Overloading your gas lines with appliances isn't safe or efficient, as it causes pressure issues that can lead to gas leaks or appliance malfunction. Some homes are only equipped with gas lines that are 3/4 inch (") in diameter, as this is a standard size for supporting major appliances.

What happens if gas line is too small?

The flame usually simply goes out and the gas continues to exit at a low rate. The lines should be sized based on the demand of the appliances connected. You may get away the same way electrical wiring does though. If all the appliances are not on at the same time (load diversity) the maximum demand may never occur.

What happens if gas line is too small for tankless water heater?

The capacity of the meter and regulator must be greater than the total sum of the maximum BTU rating of all the appliances in the home. If the capacity of the system is too small, the gas appliances will not receive the volume of gas required for proper operation.

How big of a gas line do I need?

Section 1, supplying outlets A and B, or 35 cubic feet per hour requires ½ inch pipe. Section 2, supplying outlets A, B, and C, or 94 cubic feet per hour requires 3/4 inch pipe. Section 3, supplying outlets A, B, C, and D, or 230 cubic feet per hour, requires 1 inch pipe.

How do I calculate natural gas pipe size?

Standard nominal pressure at the burner for Liquid Propane Gas is 11" of water column. Pipe length must include additional length for all fittings. Add approximately 5 feet of pipe per fitting LP Example: An appliance with a burner that requires 440,000 BTU would need a 1" pipe for a 20-foot long run.

How high off the ground should a tankless water heater be?

Your gas water heater should be 18 inches off of the ground, as per the National Fuel Gas Code. This is the standard for water heater installation requirements.

Can I use flexible pipe for tankless water heater?

You can use flexible gas tubes or water pipes for a gas water heater in most states. In states with earthquakes, they can even be mandatory. If your existing gas pipe has CSST (corroded stainless steel tubes) or has not been glued, the connection should be replaced right away.

Can I use CSST for tankless water heater?

Our flexible water CSST will save you time and money in re-piping, renovations and new constructions. It is made from lead-free stainless steel. It is also an excellent choice to connect boilers, water heaters, thermal solar systems, and tankless water heaters.

What happens if you oversize a pipe?

Oversized piping may contribute to health risks such as Legionella, sewage clogs, and odor fade. As time moves forward, plumbing fixtures and the use of plumbing systems changes, and new risks are discovered and studied.

Can PVC be used for natural gas line?

PVC Pipe

PVC pipes will work well for natural gas lines and water supply. They are generally available in sizes of 10 feet and 20 feet, and they come in varying diameters.

Can I split my natural gas line?

The pipe splitting operation can be performed in both direction from a single excavation thereby reducing the number of launch and exit pits required and ultimately limit costs.”

How long can you run CSST gas line?

Three- or six-foot long and accessible: The flexible connectors can't go through walls, floors or ceilings, nor can they be concealed. The flexible connector length usually is limited to 3 feet except for gas ranges and clothes dryers. For these appliances, 6 feet generally is allowed.

How many BTU does a tankless water heater use?

A typical propane tankless water heater (9 or 10 gallons of propane per minute) may generate anything between 25,000 and 200,000 BTUs per hour. This energy is sufficient for three bathrooms. The more the rooms, the more the gallons you'll need every day.

What size pipe comes out of gas meter?

4) Normal gas service piping from the main to the residential customer meter set is typically 1/2 inch or 3/4 inch Polyethylene (see 1a. above).

Do I need a backflow preventer on my tankless water heater?

Backflow preventers are now required by many plumbing codes to be installed in the cold water supply line from the street. Before the days of backflow preventers, the expanding water in the hot water tank could push backwards into the main water supply.

Do tankless water heaters need isolation valves?

Isolation valves are essential pieces of equipment to keep your tankless water heater in excellent working condition because they allow you to maintain it to the manufacturer's specifications.

Does tankless water heater require expansion tank?

Expansion Tanks and Tankless Water Heaters

Most tankless water heaters (electric or gas) do not need a thermal expansion tank. The reason being is that a tankless water heater only produces hot water as requested. When the hot water supply is opened, the tankless unit starts to produce hot water.