How much do they cost to buy compared to regular tank type water heaters?
About $1,000 compared to $450+ for a natural gas tank type.
Is installation involved
A tankless heater might take 200,000 btu/hr, whereas a tank type only 30,000. That means you will probably need a bigger gas line. For some homes, with slab floors and no attic, this can be challenging. Gas piping may have to go along the outside of the house or over the roof. The new gas line alone could cost over $1,000. The reason they need so much gas is that they have a large burner to heat the water up as it flows through.
How big a unit do I need?
Units are rated by the gallons per minute of hot water at a given rise in water temperature. The most common rating is for a 35 degree rise and the range would be between 5 and 10 gallons/minute. Another way they are rated is by the number of “units” (showers, laundry, dishwasher) that can be operated at the same time without a drop in temperature. Most residential units we install will operate 2 or 3 showers at once. But you will never run out, as with a tank type. For situations that require more hot water, units are easily put in tandem and linked together electronically
What about hard water? Won’t that clog them up?
Sediment build-up that eventually makes your tank type water heater start popping like popcorn as trapped water boils up through the sediment, is not a problem in the tankless system because there is no tank. Water moves through the coils as it is heated. When all the taps are closed, the flame goes out (no pilot on most).
Will I get hot water to my upstairs shower quicker?
No. It is a common misconception that demand water heaters are “instant”. If a new demand heater is in the same location as the old, hot water will not be delivered any quicker.
Can I use a circulation pump to keep hot water in the pipes?
No, not unless a small electric tank heater is installed just for that purpose. Tankless water heaters require a minimum flow to turn on the flame.
Can I use a tankless heater in conjunction with solar water heating?
Not recommended because it needs cold water coming into it. If , say, 90 degree water came from a solar panel into the intake, it wouldn’t be able to make a flame small enough to only heat the water 10 or 15 degrees, so it wouldn’t come on at all. Or it might keep going on and off and make cold water “sandwiches”.
OK, what else?
Glad you asked. One of the potential side benefits of demand heaters is that there are outdoor models that require no vent pipe at all. If your current water heater is in your garage, put the tankless outside and gain that space. Or if you currently have a heater in a hallway closet or laundry room, put a demand heater outside or in the attic. Now you have more storage space. They take up very little room.
Which brand do you recommend?
We are certified installers of Rinnai units and we recommend that brand. They are made in Japan.
How can I find out the cost for my situation?
Call us for a free estimate at 530-758-0830 or email us. We usually do estimates on Saturday afternoons
What are the down sides, besides the expense?
If the power goes out, you have no hot water. Some companies, however, make battery backups, much like a UPS for a computer, that will power the electronics required, which take very little current.