What is a Tankless Hot Water Heater?
A tankless (Instantaneous, On-Demand) hot water heater is a natural gas or electricity powered device which takes in cold water as input and raises its temperature to produce hot water when the hot water tap is turned on. When the hot water tap is turned off, water is no longer heated. Hot water is not stored hence there is no need for an insulated storage tank. Since there is no heat storage, there is less heat loss over time. Basically, with a tankless system, you are not using energy to heat water when you are sleeping, at work, on vacation, away from your cottage, etc.
Why Go Tankless?
With my plans to finish my basement underway I wanted to increase the usable space and save on hot water costs. I also wanted to make sure that I could call someone to service the unit if there was a problem. After some research I realized that one way to accomplish the first two goals would be to replace the bulky hot water tank with a compact natural gas powered tankless hot water heater.
Choosing Vendors and Installers
I looked at two tankless vendors: Bosch and Rinnai using natural gas. Although I found Bosch installers in Vaughan, there were all small companies (think 24/7 service) and none of the ones I contacted offered device rental. Although Home Depot sells Bosch devices, their subcontracted installers (at least in Vaughan) only install (to own) Rinnai systems at a cost of approx $4500. I also contacted the company from which I was renting my tank (Reliance-formerly Union Gas) to ask if they offered tankless systems since they did not advertise this service on their website. To my surprise they offered tankless heater unit rentals for an additional $13/month. Reliance also informed me that the their tankless customers save on average 10% on their water heating costs.
Energy Savings
I estimated that the energy savings would approximately cover the additional monthly rental cost and decided to go with a Rinnai device rental from Reliance.
Space Savings
My water tank took up approximately 4 square feet of floor space. However, after removing the tank, it meant for me that my basement kitchen could be 2 feet wider along a 10 foot wall. So that is an extra 20 square feet of usable space. See the the before and after images below to see the difference.
| Before: Using water tank | After: Water tank removed |
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Where is the Tankless Heater Now?
The Rinnai device is roughly the size a small suitcase and is hung on the exterior wall behind the furnace. The unit exchanges air with the outside using a 5 inch dual purpose concentric vent. The inner vent pipe is the hot air exhaust and the outer is the fresh air intake.
| Tankless unit installed | Concentric vent (16 in. long x 5 in. diameter) |
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