Obviously, there are some advantages to installing a tankless water heater: there is no huge tank to lift and mount, and there is no need to find the proper blocks or other supports to balance the heater on.
The “tankless” part of “tankless water heater “ takes care of that.
This does not mean, however, that installing a tankless water heater is a simple job. It can be done with the right tools and a bit of skill, but if you do not have the proper tools or a good touch with those tools, it is probably best to hire someone to install this type of heater.
You might think that without the tank factor, installation should be cheaper for this type of hot water heater, but the opposite is usually true.
Considerations for Installing a Tankless Water Heater
If you can use the same location where you had a previous water heater (even one with a tank), it will cut down on your workload. You will already have a vent pipe, water pipe and gas line extension in the area where the previous heater rested.
You will need new water pipes to supply your hot water heater with water. This will require soldering, so you are going to need a torch for this job. If soldering is out of your league, then call a professional to install your water heater.
If, however, your tankless water heater has a different sized vent pipe, you will need to acquire a new pipe and perhaps widen the hole where it will go.
Some tankless water heaters also need a separate pipe for fresh air intake, which means you will need to buy that pipe and create an additional hole for it.
In a sense, you want to work backwards. In other words, hold the tankless heater up to the wall where you want to install it. Make sure that all of the proper pipes line up correctly with your heater before you start to make holes and install the pipes permanently. You do not want to have an elaborate system of pipes already mounted, only to discover that the top of your tankless water heater does not line up with your assemblage.
As you cut thimble holes for installation, be sure to check your local codes for any requirements. You do not want to insert the thimble until the vents have been installed and you have verified the angles of those vents.
Tankless water heaters can be electric or gas, so that will influence the amount of work that you have to do. Gas water heaters will require a few extra steps as a valve is installed on the existing gas line and a new gas line is run from the valve to the heater. Of course, if you had a gas water heater previously, a gas tankless water heater would make sense; the same goes for sticking to electric if you had electric.