How to Run Your Water Heater without Electricity

    Running Your Furnace or Water Heater without Electricity

    power failure protection for your tanklessToronto and the Greater Toronto area were hit hard with an ice storm late in 2013.  The weight of all the ice snapped branches and brought down trees which in turn took down the hydro to hundreds of thousands of homes.  Some home owners were without hydro for several days and experienced plummeting temperatures.

    Tankless water heaters use very little electricity and can thus be safely run with a common battery backup designed for computers and electronics. Rinnai has outlined a few systems they trust in a technical bulletin, I would think that those battery backups would be sufficient for other brands of tankless systems as well.


    Battery Backup Bulletin

    Rinnai has put out a technical bulletin providing 3 battery backup systems approved for use with their tankless water heaters. Check them out below.



    Without electricity your furnace, water heater, and air conditioner won’t run.  But we have some easy tips to help you get your systems back up and running through these situations.

    Run Your Water Heater With No Electricity

    This completely depends on your homes water heater and each type has a unique situation.

    Electric water heater – sorry, you are out of luck, it just won’t run until the Whole home generator that can power your electric water heater as well as your entire home. hydro comes back on.  Even most generators likely won’t produce enough power to run your electric water heater; they consume a lot of electricity.  There are a few systems out there that are sized adequately to power your entire home. A system like the one pictured here has a fully automated transfer switch so it instantly turns itself on when hydro goes out and shuts itself off once hydro is restored.  It can power your homes electric water heater and everything else for that matter, click the picture to check them out.

    Power vented water heater – These systems need electricity to run the fanWater heater battery backup system that pushes exhaust gases out of your home but the system uses natural gas or propane for the primary fuel.  If your system has a normal outlet plug coming from the exhaust fan it is a candidate for a battery bank backup system similar to the one pictured. The benefit is that you get a surge protector built in, the larger the system you you purchase the longer your system will run. There are a lot of different sizes and prices, the picture is a link to a similar system we use at home.

    Tankless water heater – Very much like a power vented system above a tankless needs electricity to run the fan that moves the exhaust gases out of your home produced during the combustion of propane or natural gas. Just like above its good to put your tankless on a surge protector and I would recommend buying the largest battery backup you can as a tankless can consume a bit more power than a power vented water heater.

    Atmospheric Vented water heater – The venting is very restrictive and difficult to instal but homeowners that have one of these hot water tanks will have no problems during a power outage as long as propane or natural gas are provided, no electricity needed.


    How to get your Water Heater Running During a Power Outage


    This is easy; visit Costco, Best Buy, or you can even purchase off Amazon here.  Look for a battery backup system that is sold for computer or home electronic systems.  At our house we purchased the largest system offered at Costco for $199.  It simply plugs into the wall and charges itself with its built in smart meter and automatically kick on as soon as the power drops.

    Depending on the size of the battery backup you purchase your water heater could run for several days during a power failure. Of course this depends on you either having municipal water or some type of backup power for your pump if you are on a well in the country.

    When using a tankless it really should be standard practice to have your system hooked up to a battery backup, not only is it a great surge protector protecting your investment but also a sure fire way to eliminate any unexpected shutdowns during electrical storms, wind storms, ice storms, and all the other threats to our electrical grid.


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    3 Comments

    1. Pulling plastic-sheathed cable through holes in the framing is a lot easier if you straighten the cable out first. If you simply pull the cable from the center of the coil, it’ll kink as you pull it through the studs. The trick is to lift a handful of coils (four loops will reach about 12 ft.) from the center of the roll (left) and toss them across the floor as if you’re throwing a coiled rope.

    2. makes more sense than a 60gl tank

    3. Nice work Eric, you wont regret it. Like I’ve said the best thing about gas water hentaig as opposed to a hot water tank is that you heat the water to the temp you want to use it at. For example with a water tank you heat it to say 131 F but then if you have a shower you mix cold water into it. That’s so stupid. You heat water and pay for that hentaig only to cool it down to use it, but with gas you only heat it to the temp you want to use it at, so shower at say 109 F means you only pay to heat the water to 109 and not 131 F.Happy endless hot water showers too!

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