Tankless Frequently Asked Question

     Tankless Facts and Questions

    Personally, I thoroughly enjoying answering the phone and responding to peoples question regarding tankless water heaters.  Some questions are fairly common and some are very specific; but for me they are all interesting in their own manner.   

    We have answered question from nearly every State within the US as well as every Province in Canada.  Even though we are located in Toronto, Ontario we are still occasionally able to help someone out even though they are out of our service and installation area.  

    We have thousands of visitors to our site every month and as a result have installed thousands of tankless water heaters throughout Southern Ontario.  Our tankless installations range from residential homes, condos, town homes, co-ops, factories, franchises, and commercial applications.

    I feel we are a well established authority on tankless water heaters and can provide a very thorough and helpful FAQ section.  It will be an ongoing initiative and we welcome suggestions as well as any additional questions you may have regarding your water heating systems.


    Call Us at : (647) 925-1930


    1. What is a tankless water heater?
    2. What types of tankless systems are there?
    3. Is a tankless installed in the same place as my old conventional tank?
    4. Can I expect any savings from a tankless?
    5. What is the cold water sandwich?
    6. The Cold Water Sandwich Facts – (part2)
    7. Which would be the most reliable tankless system for a home in the GTA 
    8. What sort of venting do I need?
    9. Flow Rate Calculations
    10. Can I break my water heater rental contract?
    11. How much will a tankless cost?
    12. Can I rent a tankless? How much will it cost?
    13. Are there commercial tankless systems?
    14. What is a Combi-Boiler?

    What is a tankless water heater?

    In general a whole home tankless water heater or on demand water heater replaces your tank type system with one that can heat water only when you need it.  A tankless hangs on the wall and offers significant space savings simply by overcoming the storage tank most systems employ. 

    A tankless has a very effective heat exchanger that can almost instantly take cold incoming water and make it hot. This technology has proven to reduce your water heating energy bills month over month.

    What types of tankless systems are there?

    Of course there are several different brands and manufactures of tankless systems but there are also different types.  Most manufactures will have both a condensing and non-condensing tankless available.

    Regular Tankless – A single primary heat exchanger is used to heat water to your desired temperature on demand and as you need it.  This type of tankless is commonly around 82% to 84% efficient (examplesRL75i or RTG-95DV).

    Condensing tankless – These systems use two heat exchangers, the primary exchanger is used to provide all the hot water your home needs.  The second heat exchanger is positioned near the top of the system and captures normally wasted heat from the exhaust to preheat the incoming water adding roughly 12% efficiency increase (examples RU98i, NR210 or the 95DV).


    Is a tankless installed in the same place as my old conventional tank?

    This question has a lot of factors that come into play.  First off a tankless is hung on a wall so you will be gaining a lot of floor space your water heater occupied in the past.  Secondly the venting requirements are different for a tankless.  Sometimes the old pipes can be used sometimes they can’t.  The homeowner can also help choose where the tankless is installed, maybe on an opposite wall or somewhere nearby are all feasible.  As a rough example we have a diagram showing the installation requirements for a Rinnai RL75i.


    Can I expect any savings from a tankless?
    Again we have a question here with a number of unknown factors.  In my experience most homeowners do notice a savings on their water heating bills but don’t take my word for it here is definitive proof.  The CMHC (Canadian Mortgage and Housing Corporation) relatively recently did an extensive study on tankless systems to verify claims about their performance and energy efficiency within the Canadian marketplace.  The results were actually quite surprising and here is a very brief rundown. 

    – Overall increase of 2% in hot water use

    – On average a 46% reduction in natural gas used

    – A tankless saved roughly 1 meter cubed per day

    Read the full Tankless CMHC report (pdf)


    What is the hot water sandwich?

    This is a situation where the very start of the cold water flow is introduced into the heat exchanger before it fires and doesn’t spend enough time being warmed up before being pushed out.  This happens most often when a tankless repeatedly starts and stops, such as bushing your teeth or when washing hands.  It most situations the brief temperature fluctuation is completely unnoticed by the home owner.  Manufactures have all but eliminated this issue in the newest generation of systems.


    Which would be the most reliable tankless system for a home in Toronto, the GTA or Southern Ontario?

    After years of installing these systems we only rent a few specific models.  If you think about this and understand that when we rent a tankless we are on the hook for all repairs and issues that come up just like a conventional water heater.  Thus our choice in rental tankless water heaters are models we know know from experience will be the most reliable and reduce our service costs. 

    1. Rinnai
    2. Rheem
    3. Navien


    What sort of venting do I need?

    It is extremely important that a tankless is vented to both Ontario as well as the manufactures code.  Your tankless cant be vented up your chimney with a liner in it, it is just not legal.  To vent a tankless a hole has to be punched in the wall to run the vent pipe.  In some instances a second pipe is used to bring fresh air into the tankless to completely isolate the system from your homes air. 

    In terms of venting required it is pretty easy, a non-condensing tankless will need stainless steep vent pipe as the exhause gases are still quite hot when exiting the unit.  A condesning tankless can use 636 or another approved plastic vent piping since the secondary heat exchanger removes otherwise wasted heat to prewarm the incoming water.  The normally hot exhaust is cooled sufficiently that a plastic pipe is a more than adequate as a means of containment. (See the difference between a condensing and non condensing tankless).


    The Cold Water Sandwich

    This is not something to worry about anymore.  Tankless systems today are much smarter and have developed ways to deal with this issue.

    Cold water sandwich background – Basically when you turned on the hot water tap the already warm water in the heat exchanger was pushed out and cold water would enter and leave before the burner could fully heat it.  Thus there would be a brief moment of colder water until the burner could catch up with the flow.

    Today’s tankless systems slow the incoming water down for a few seconds to ensure it leaves the system at the appropriate temperature.  More importantly who starts a shower and gets in immediately anyways? Pretty sure every person starts a shower and waits a minute for the water to reach the bathroom anyways… The cold water sandwich is a non issue.


    Flow Rate Calculations

    You should definitely keep an eye out for this stat.  Most manufactures of tankless systems give a flow rate of their water heaters at different incoming water temperatures.  Here is Southern Ontario the 77 degree Fahrenheit increase is what should be used as your baseline winter water output.

    Watch out as some companies like to reference the 45 or even 35 degree water output rates so they can put in a smaller cheaper system (we always install proper whole home systems).  Also watch home renovation depot stores here in Ontario, they have smaller systems that just aren’t capable of meeting hot water needs with our winter water temperatures.  They target homeowners looking to do the job themselves and want a system that’s the same price as a conventional water heater.

    A conventional 40 or 50 gallon tank can output about 7-9 gallons of pure hot water per minute (well, at least until the tank runs out – 4-6 minutes).  A tankless in the summer will easily produce that same 7-9 gallons but it does drop in the winter.  The coldest winter water here will drop the output of most tankless systems into the 4-6 gpm range (still sufficient to run two showers and another appliance).


    Can I break my water heater rental contract?

    Yes, almost all companies allow you to get out of your rental water heater contract.  The question really becomes how much you will pay to break the contract.  Companies like Reliance and Direct Energy are large and accountable and thus have fair contract breaking rules.  If you are 12 or more months into your contract it may be completely free. 

    • Breaking Your Reliance Water Heater Contract
      – Water heater one year old or less – $200 account closure fee
      – Water heater one to nine years old – $40
      – Water Heater ten years or older – $0
      – To have reliance pick up their water heater from your house – $65 gas – $125 electric
      – Have Reliance drain and disconnect their water heater – $125

    If you were switching to us as we always remove and return the tank to Reliance on your behalf for free. 

    • Breaking Your Direct Energy Water Heater Contract
      – You may cancel a Direct Energy water heater contract at any time by calling or notifying in writing. 
      – Direct Energy simply says that there may or may not be fees associated with your termination.
      – Call Direct Energy Cancellation Line at 1 (800) 493 3034 for more info
      – They also charge a 75$ disconnection and removal fee if your new water heater company doesn’t offer the service.

    Check your water heater rental bill to see what you are paying to rent your conventional system.  Our tankless rentals are 29$ a month which is usually only 10$ more than what most home owners pay for a 40 or 50 gallon tank.  Remember a tankless is around 95% efficient and a conventional tank only 45%, making the switch may not be as expensive as you think.


    How much will a tankless cost?

    Each home we install a tankless in is a custom installation, thus giving you an exact price over the internet is nearly impossible.  We have installed thousands of systems and thus have a baseline and can give the average low and average high price.  It would be a safe bet to assume that your tankless would land somewhere in between these baselines.

    Low Price – $2600
    High Price – $3400

    Now there are a few things to consider with these prices.  First I have included both condensing and non-condensing tankless systems.  If you decide on a non-condensing system you will be more in line with the lower pricing whereas a condensing system will be along the higher range.  Secondly I have included all sizes of tankless systems within this price range; from:

    • Navien 180 to the biggest Navien 240
    • Rinnai RL75i to the largest Rinnai RU98i
    • Rheem RTG-84DV to the largest CRTGH-95DV

    Price includes original tank drain and removal, new venting installation, mounting and full hook up of new tankless.

    To have your tankless price narrowed down a bit give us a call to discuss your situation, otherwise we can send a REP out to address your homes unique needs for an exact price quote. (647) 925 1930


    Can I rent a tankless? How much will it cost?
    We rent both tankless and conventional water heaters.  Renting a tankless will net you all the same rental benefits that a conventional water heater will.  But, renting a tankless will net you all the energy savings a tankless has to offer.  A recent study on tankless systems done by the Canadian Mortgage and Housing Corporation found that home owners on average save 46% on their water heater energy bills.

    Having installed so many tankless heaters we can comfortable tell you that your rental on a tankless will be between $29 to $39 depending on the brand and the size of the system you decide to go with.

    Remember when you rent a tankless the system and installation is free. To get an exact monthly fee quote you will need to give us a call to discuss. (647) 925 1930


    Are there commercial tankless systems?

    Several of the tankless manufactures make a commercial tankless system. 

    Generally it is very similar to the residential version but with a bit more power and the ability to heat water to a higher temperature.  We have installed a tankless in Toronto salons and spas, in numerous Tim Horton’s, in Wendy’s, and in hundreds of different commercial applications.

    A Commercial tankless has the ability to scale up as the business grows.  Simply purchase a new system, hook it in line with the current tankless and just like that you double the hot water production.  In the case of Navien up to 16 units can be linked together producing upwards of 175 gallons of hot water a minute.

    A tankless will hang on the wall, vent easily, and have an unlimited supply of hot water.  Best of all, when you close the doors for the night the tankless doesn’t heat hot water continuously like a storage tank does, so you are saving money.

    We have specialized commercial REPS that can visit you at your business to discuss your needs and to see if a tankless water heaters can meet your needs.

    What is a Combi-Boiler?

    These are new systems that most of the major tankless manufactures are starting to produce. Basically they are designed as wall hung boilers capable of producing all of a home’s heating as well as hot water needs.
    Functionally they are almost identical to a tankless except they use an additional small heat exchanger to isolate potable water from the heating water (or glycol). This additional step does reduce the hot water production by about .3 gallons per minute but realistically it is very minimal.

    Homes that currently use a radiant heating system can upgrade to a new combi-boiler and remove their floor mounted system with little issue. This not only saves a tonne of space but also can increase your homes heating efficiency substantially.
    Since combi-boilers are able to provide all of a home’s hot water needs the hot water tank in your basement can also be removed, if it’s a rented system send it back and save yourself some additional money.

    There are three primary tankless manufactures that produce comparable systems.

    1. Rinnai – E110C, E75C
    2. Rheem – H95
    3. Navien – NCB180, NCB210, NCB240