We received many comments to our Part 7 article in this series on tankless water heaters. One of those who left a comment, Ginna, made some good points. What I would like to do is to post her comment followed by my thoughts as our article of the day today.
OK, here is Ginna’s comment unedited:
Dan,
I’m curious as to why you only got quotes on the Rinnai. There are other models which allow for horizontal venting. (The Bosch comes to mind, is carried at Home Depot, and is much cheaper.)
I just had an audit in preparation for a big renovation, and both gas installers I’ve talked to think the Rinnai is seriously overpriced.
I’m leaning towards the Bosch with a DWHR system. The total cost will be less than $2500, and with the $530 back (including the DWHR unit), I’m doing pretty well.
BC Hydro (who have a vested interest in pushing electrical), recommend gas for tankless if possible:
http://www.bchydro.com/business/investigate/investigate831.htmlIn particular, the wiring and amperage requirements of the electrical may surprise you - they far exceed a standard tank model.
Electric models also have far lower temperature rise.
Those were factors in my decision anyway.
Cheers,
Ginna
And now, here is DailyHomeRenoTips.com response and additional thoughts (warning: this is a long article without any pictures):
Hi Ginna,
Many thanks for your comments.
First, I assume when you say “I just had an audit …” you are referring to the energy audit under the ecoENERGY Retrofit grant. Excellent! We didn’t know any better and lost out on over $1,000 in Federal / Provincial grant money because we had proceeded ahead on some home reno’s prior to learning about the ecoENERGY Retrofit program.
Hence why our site’s big focus on the ecoENERGY Retrofit energy audit and energy audits in general.
Why just the Rinnai natural gas tankless water heater? Well, quite frankly, in the area where we live (Southern Ontario) it has been the only one that was publicized at the time we were investigating (spring 2008). Now that most of our spring / summer home reno activities are slowly getting behind us, we may look again at other brands. I have heard good things on Bosche and Takagi natural gas models too. As well, I’m not so convinced that electric tankless (at least from a certain manufacturer) are not viable, especially in conjunction with a solar water heating or solar radiant heating systems.
Yes, the cost you quote for a Bosch and DWHR combined certainly is very good from what I have seen and a good combination to install. I’d like to go with the DWHR unit as well, but as we have previously written about it’s not in the cards with our pre-finished basement.
Unless the Bosch is somehow different, that is if it also needs special venting line the Rinnai natural gas tankless water heater, we will face the same issues we have with the Rinnai, i.e. having to be installed 30 feet away from the current hot water tank resulting in wasted energy in heating the water having to travel 30 feet + wasted water as well.
Do be sure that the tankless natural gas water heater complies with the ecoENERGY Retrofit guidelines. It currently has to have an Energy Efficiency factor of 0.80 or higher, otherwise it does not qualify for the ecoENERGY Retrofit grant. One of the two Bosch units in the BC Hydro link would then, as I understand it, not qualify.
That BC Hydro link is really good. Many thanks for sharing. I like the part about using a tankless water heater with “…modulating controls that increase or decrease energy input to maintain the selected outlet temperature despite varying flow rates and inlet temperatures”. Very important in cold weather climates such as ours in Canada, although the DWHR device will help to heat the incoming water for you, which is the only benefit for a DWHR device with a tankless water heater (thus reducing it’s benefit vis-a-vis a DWHR device with a hot water tank).
As far as flow rates, natural gas vs electrical, a few thoughts. Again, I am new at this and not an electrician or contractor so if there are errors please point them out to me:
- The BC Hydro page does not include all natural gas or tankless models. For example, it is dated 2006 (at the bottom of the page) and does not include the Rinnai natural gas model (which is newer … circa 2007 I think) or any of the SEISCO electric model.
- From the SEISCO web page (which is the same type of source used by the BC Hydro web site, i.e. the manufacturer’s data and not separate testing by BC Hydro), for the 4 chamber RA-28 model, the GPM (Gallons Per Minute) flow rates are:
Temperature Rise GPM
95° 2.0
76° 2.5
64° 3.0
48° 4.0
- The above temperature rise and flow rates combinations for the SEISCO RA-28 model are actually better I think than for the Bosch natural gas tankless (which was your preferred manufacturer but was not as strong as the Takagi model) device with it’s flow rates below taken from the BC Hydro site :
Temperature Rise GPM
100° 1.5
75° 2.5
50° 3.2
- Yes, in many areas electricity is more expensive than natural gas. However, to some degree the ultimate decision on type of water heating device depends on what is more important to the individual decision maker. Natural gas tankless water heaters directly consume a non-renewable resource, i.e. natural gas. An electric tankless water heater’s consumption of non-renewable resources depends on the power source of the electricityto the house. For example, a coal burning power plant is more polluting and consumes another non-renewable resource (i.e. coal) while a hydro-electric power plant neither consumes a non-renewable resource nor does it generate any pollutants. And, with the cost of solar PV panels both on the decline and possibly becoming very mass produced, an electric tankless water heater where the power is generated, even in part, by solar PV panels is both totally non-polluting and consumes zero direct / indirect non-renewable resources. Here is a link to an interesting article from USA Today on Monday July 28, 2008 on silicon valley firms (yes, that silicon valley) getting involved with solar PV panels which cudda / shoulda reduce in the near-ish term solar PV panels.
- Yes, additional electrical panel expansion and wiring can be required for most homes for an electrical tankless. Like special venting for a natural gas tankless that is a one time setup cost. However, I am personally paranoid of needing any special venting more than what is needed for our current hot water tank. At least for the Rinnai model, neither installation firm could install it anywhere except against the outside wall. What if the special venting breaks? There is no such issue or concern with an electrical tankless water heater.
- I like simple. I like how I can have installed an electric tankless water heater pretty much anywhere in the house.
I’ve gone on long enough
I will likely (can’t promise a future type of things with 100% certainty) investigate another natural gas tankless model. However, after the mis-adventures with just our front door from a certain international building supply retailer and their sub-sub-contractors, if they cannot install a replacement front door right the first time, I am even more concerned about their ability to install something significantly more complicated and dangerous such as a natural gas tankless water heater.
Thoughts, anyone? 
11 responses so far ↓
1 Paul // Jul 31, 2008 at 1:00 pm
Given your periodic comments on financing renovations I would be very interested in your views on the Rental Tankless Hot Water offer from Newten Home Comfort (http://www.newten.ca/). For ~$30 a month you can rent a Rinnai natural gas hot water heater from them. Installaion is included and they claim that this is still eligible for the ecoEnergy rebate. We are considering this since we only expect to be in our current house for another 3 years or so. Thoughts?
2 A // Jul 31, 2008 at 1:46 pm
I like the discussion. It makes people think, ask questions and go find answers. There will be a point where it’ll come down to pure personal preference.
Some comments for the other gas tankless models.
Do you think the 30 feet will make *that* much of a difference?
Bosch- friend put one it. Has separated intake and exhaust vents, so that means putting up *two* ducts in the house but I think you’re allowed to run the ducts farther.
Takagi - another friend has one. IIRC, only exhaust but draws are “from the room” which means you need a fresh air intake into the room (from the outside).
In both cases, there are restrictions on how close the intake and exhaust are.
Rinnai - integrated exhaust/intake. Makes for a big pipe but there’s only one and no open “hole” to the outside.
Oh and one more comment on hydro-electrical, there is a huge enviromental impact when you dam up a river and flood everything upstream.
Anyways, just food for thought.
Cheerio!
A
3 Dan // Jul 31, 2008 at 2:35 pm
Hi Paul,
Per the link you provided you can rent one for $34.71 / month (likely prior to taxes, but we’ll leave taxes out of the equation for simplicity).
I cannot tell you if you will or will not be eligible for the ecoENERGY Retrofit grant. I could not find anything on their web site stating you would still receive the grant if you were renting. I strongly suggest you email them directly and ask them to confirm to you in writing. Logic tells me to question this. Why would they offer you $250 (plus Ontario another $250) if you are not incurring up front costs. Here is the link to the ecoENERGY program web page with how to contact them: http://www.oee.nrcan.gc.ca/residential/personal/contact-us.cfm?attr=4
Also email the Ontario government and ask them the same thing.
I am assuming, of course, that you already have the D (i.e. the first) Energy Efficiency Assessement done on your house, right? You have to have this energy audit done before any home renovations to be applicable for any ecoENERGY Residiential Retrofit grants.
$34.71 per month and they take care of all the installation. To me it depends how environentally conscious you are. At the extreme, if you have mortaged your house to install solar PV panels, then any question of rental costs is mute. However, if you need financial payback, I’m not sure you will get it at $34.71 per month. Why? Here’s the link to the article we wrote containing our numbers in this regard: http://dailyhomerenotips.com/2008/05/06/tankless-water-heater-part-5-the-second-quote/
Are you renting hot water tank now or do you own? Do you have to change now? Three years is not a long time.
What is your estimate of energy costs to heat your hot water each month now and how much savings are you being told you will realize from this? For us, we would only save around $28 / month ($15 for the rental of the hot water tank and $13 for energy usage [natural gas]).
If it is from a pure financial perspective, I would likely declide their offer. However, I would suggest to get them in and have them work the numbers and show you the financial payback of renting.
Lastly, in the long run, renting anything is usually more expensive than buying. Just think of a car lease vs purchasing a car; not the monthly payments but for the entire life of the car.
You know that this firm will make money and will recoup their cost for installing the Rinnai by including in the $34.71 / month am an amount to reimburse them for this installation cost, plus interest.
I hope that helps,
Dan
4 Tom Garven // Jul 31, 2008 at 6:41 pm
Hi Dan:
Just found this site today doing a Google search. So if my comments are out of line please delete.
I prefer a heat pump water heater for the following reasons.
1. Less expensive up front cost [about $550 installed].
2. More efficient than either a gas or electric tankless system.
3. No need to upgrade my electric panel to service the electric model.
4. I don’t have piped in Propane or Natural Gas therefor tankless becomes very expensive for me.
5. Heat Pump water heaters give back at least 2,000 btu’s of heat for each 1,000 btu’s of energy input. Most units are 2.2:1 energy gain.
6. Heat Pump water heaters can be installed on any existing gas or electric water heater.
7. Heat Pump Water Heaters are an ideal solution for solar since they can work when the sun doesn’t shine.
However they are not perfect.
1. They won’t work below about 35 degrees F.
2. If you live in a humid area you will need a condensate drain and;
3. They will remove about 7,000 btu’s/hr. from your heated space in the winter.
Just thought your readers would like another perspective. Here in Arizona we install them in the garages where our water heaters are located since they do not require any winter heating.
Tom Garven
Lake Havasu City, AZ, USA.
tomgarven@hotmail.com
5 Anonymous // Jul 31, 2008 at 7:16 pm
Note that the BC Hydro link is for business customers, not residential applications. And the reason they don’t recommend electrical instantaneous water heaters is because all but the smallest sizes are illegal in BC under the electric tariff. The demand for electricity when water is being heated is enormously high, which puts a great strain on the electrical grid.
6 Dan // Aug 1, 2008 at 12:49 am
Hi Tom,
Thanks for your sights about heat pumps. I personally do not have any experrience with them because as you say, they won’t work below 35 degrees F. As I reside north of the 49th parallel, that wouldn’t work too well for a large amount of the year.
I have heard good things about them on other forums, etc. for those who do live in climates where it doesn’t snow.
Thanks for the perspective.
Dan
7 Dan // Aug 1, 2008 at 12:54 am
Hi Anonymous,
Do you have any sources with links you could provide regarding (A) “…all but the smallest sizes are illegal in BC under the electric tarrif” and (B) “…enormously high, which puts a great strain on the electrical grid”. That would be very helpful.
Thanks,
Dan
8 Peter // Oct 15, 2008 at 3:13 am
Go with a solar preheat system. Not everything in life is about “payback”. Sometimes you do things because it is the right thing to do. Solar power produces no emmissions. Your lungs will thank you
9 Dan // Oct 15, 2008 at 10:36 am
Hi Peter,
I agree …. about sometimes you do things because it is the right thing to do. However, IMO it has to be a balance; not the type of balance that the Harper government uses (geeesh!) but when it comes to my mortgage and line of credit and …
If I was to do the right thing then I would be totally off grid. That would set me back at least $50,000. Our web site doesn’t make much more than to pay for the site hosting fees.
I need at least 5-ish years financial payback on any investment. I think that is reasonable. What if I loose my job…who will pay for my debts then?
Likely in time costs will come down and efficiencies will improve to the point that solar water heating is a 5 year payback, even here in the north. We are awaiting the installation estimate from the firm in our area participating in the new solar water heating mass pilot deployment that we have written about previously. At least we can all do that much, i.e. get the true cost of what different energy efficiencies will cost rather than what someone says it might cost.
http://dailyhomerenotips.com/2008/08/28/ecoenergy-subsidized-solar-water-heating-coming-to-a-dealer-near-you/
We did purchase a solar air / space heater and will be installing it in a couple of weeks. That one is much less complicated & less money and yes, we will write about our experiences with it as we go.
Cheers,
Dan
10 John // May 25, 2009 at 4:00 am
hello,
i’m wondering why people rent there water heaters?
you pay 15.00 monthly you said
11 Dan // May 25, 2009 at 11:10 am
Hi John,
Likely history (e.g. no one likes change). In my case my parents rented and every house I have ever lived in came with a rental water heater.
Since I’m still not 100% committed to a hot water tank vs solar vs tankless in the long run, it makes sense (to me) to continue to rent vs buying the heater.
Dan
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