FHB Logo Facebook LinkedIn Email Pinterest Twitter Instagram Plus Icon Close Icon Navigation Search Icon Navigation Search Icon Arrow Down Icon Video Guide Icon Article Guide Icon Modal Close Icon Guide Search Icon Skip to content
Subscribe

In every issue you'll find...

  • Expert insights on techniques and principles
  • Unbiased tool reviews
  • Step-by-step details to master the job
  • Field-tested advice and know-how
Subscribe Now!
Subscribe
  • How-To
  • Design
  • Tools & Materials
  • Videos
  • Blogs
  • Forum
  • Magazine
  • Members
  • FHB House
  • Podcast
  • Join
  • Log In
Subscribe

Discussion Forum

Discussion Forum

Direct Vent Water Heaters

DonCanDo | Posted in General Discussion on September 14, 2009 02:40am

As of 2 years ago, my furnace is a direct vent which means the only reason for a chimney is the water heater.  I’m about to have a new roof put on and I was thinking that this might be a good time to get a direct vent water heater and take down the chimney.

On the plus side, by removing the chimney, I don’t have to maintain it (it could use some tuck pointing) and I never have to worry about any leaks.  It also creates space in the bathroom for a small linen closet.

On the down side, there’s cost and reliability.  They don’t sell direct vent water heaters at the local big boxes so I wonder if they’re mainstream products yet.  I don’t want to help test new technology.  Anyone have any first-hand experience?

Reply

Replies

  1. User avater
    Yossarian99 | Sep 14, 2009 02:50pm | #1

    I wish I had the brand name for you of the water heater we went with but sorry I don't.  I'm not sure why the big box does not carry them, but they are mainstream.  We had ours installed in the old house to help make better use of the basement space and position it next to a drain, worked quite well, good luck.

  2. wane | Sep 14, 2009 03:10pm | #2

    by "direct vent water " I assume you mean tankless?  HD caries them here in Ont but they are a hard sell at 1400 (vs 4-600 for regular HWT).  The temp differential in the winter is hard to keep up with.

    1. DanH | Sep 14, 2009 03:15pm | #3

      There are also "direct vent" (induced draft) tank-type heaters. I've never seen one in a big box, save for one in Menards probably 20 years ago.
      As I stood before the gates I realized that I never want to be as certain about anything as were the people who built this place. --Rabbi Sheila Peltz, on her visit to Auschwitz

    2. DonCanDo | Sep 14, 2009 03:29pm | #5

      by "direct vent water " I assume you mean tankless?

      No, I mean one of these.  That's a link to Lowes website, but I've never actually seen it at Lowes.

  3. fingers | Sep 14, 2009 03:25pm | #4

    I may be getting this all messed up since I'm familiar with oil fired boilers and not furnaces, but we use a "boiler-mate" to heat water so the water heater does not need its own venting.

    The water tank is actually a heat exchanger that gets its heat source as a zone off the boiler. I don't know if you can do something similar with your furnace.

  4. TooManyToys | Sep 14, 2009 05:33pm | #6

    I don't think the market is that big in this area due to the cost. There are direct vent units, both in tankless and tank versions. What is coming up are the newer condensing high efficiency units, being mentioned on many of the the energy sites for release in late 2009.

    The AO Smith site has a good list of the different types available in one location.

    http://www.hotwater.com/products/residential/gas.html

  5. PedroTheMule | Sep 14, 2009 05:53pm | #7

    Hi Don,

    Give you some rumor here.....a neighbor had a direct vent unit which failed after appropriate use and years....went to get another, couldn't find one and started asking why?......was told that they were no longer code compliant in that region....he never did get a straight answer but found one a couple of hours away across the state line.....bought it, hooked it up and has been just as good as the last one....the only thing he ever did get from anybody was something about fire safety.....he figured his last one ran almost twenty years without a fire and and he was venting through cinderblock and brick so what could burn.....who knows??????

    Secondly consider.....many older chimneys are a structural part of the house so you'll need to consider this if you remove it entirely. If you only remove the portion above the roof line, be sure to insulate it inside/out all the way down past the unheated attic and such before you cap it and be sure to securely close all inputs so the next homeowner doesn't vent something to nowhere in the future.

    Otherwise......have fun!

     

     

    View Image  

    1. User avater
      Matt | Sep 25, 2009 01:51pm | #23

      Re the code compliance thing, who was your friend dealig with?  People in a big box store?  We install direct vent gas water heaters here in NC all the time.    You too are NC - right?  BTW - what area?

      1. PedroTheMule | Sep 25, 2009 03:30pm | #25

        Hi Matt,

        He did check HD & Lowes and got the run around code excuses which he wasn't really taking to heart as he couldn't find anything in the NC building codes against it at the time....he was in Fuquay-Varina at that time. As mentioned he got the run around of excuses and knew that.

        Then he went to his supplier, PSNC......they wanted to put in a whole new fandangled blower unit with new gas lines and pvc feed/exhaust for high $.

        As a single guy that traveled a lot, all he wanted was the same simple little heater he'd always had, only the old one was worn out.

        My guess is the big boxes simply didn't want to go to the effort to order one and PSNC wanted to feed all their employees steak for a month. All of this was during the building boom when everybody was about the fastest easiet buck......

         

         View Image  

        1. User avater
          Matt | Sep 26, 2009 04:37am | #27

          What area do you live in?  I'm just interested in what BTers are in what area of NC.  I'm in S Raleigh not far from Fuquay.  Send me a post directly if you want to keep it down on the down low....

          Edited 9/25/2009 9:56 pm ET by Matt

          1. PedroTheMule | Sep 26, 2009 05:15am | #28

            Let's do some country lunch buffet.....my treat......

             

             View Image  

  6. BigBill | Sep 14, 2009 06:08pm | #8

    By direct vent do you mean the forced air induction type that vents throug PVC?  They work great. 

    Or is Direct Vent a different animal?

  7. User avater
    BillHartmann | Sep 14, 2009 07:53pm | #9

    Been there, done that.

    And for basically the same reason, plus another.

    I had a utility closet with 2 furnaces and a water heater. Used a single flue, which in itself was not a problem for me. And a vent with outside combustion air, which was the main problem. It communicated with the house air. Leaving a large air leak.

    Replaced it with a direct vent furnace with external combustion air. And a direct vent WH similar to the one that Lowes has.

    As far as I can tell they are basically the same as modern vented WH, except that it instead of a vented grill around the bottom for air it is sealed. What you don't see is that on top that there is a collar and then a duct down the back to supply combustion air to the burner.

    The valve, burner, tank, etc are all basically the same as a standard WH.

    One caution is that if space is tight these are shorter and thus fatter than standard WH's.

    As someone else mentioned there are also power vented units. Basically they mix enough air into the exhaust to cool it down so that you can vent them out the side. But you can have much more pipe on them then on direct vents. Most of them are not sealed combustion if that is important to you, but there are seal combustion versions available.

    Now those are a completely different design. As they have an electrical thermostat that starts the fan, and air pressure switches to verify draft, electronic ignigtion, and solenoid gas valves.

    If this had come up 2 months ago I could have given you model numbers and brands.

    I ended up with the State. It is same as AOSmith. They include a double wall flex and cap. Some of the other models venting is separate items that you have to buy. And the American WH (Lowes) used rigid ducting, which is a little more difficult to install. Maybe a lot more.

    Also the State has an EF of .62 which was enough to get a small rebate from the gas company. The American is .59

    If I recall Reliant is also the same unit as the State/AOSmith.

    I paid $1100 for the State Unit. That included a $100 "warranty extension kit" and sales tax.

    If want to go with Lowes, verify if the venting kit is included. The price that I saw on those was a $200 or so.

    All of these have short warranty.

    Some manufactures off a "warranty extension kit". The most important part of the kit is a 2nd anode rod that goes mount through the hot water connection. It also include a warranty sticker and a pair of heat traps, although the WH came with heat traps.

    But you can get 3rd part anode rods to do the same thing, but without the sticker (and "warranty").

    WARNING - WARNING

    If you do install the anode or thing that you will pull the exist anode and replace it in the future unscrew it before installing. And get a couple of people and and cheater bar on the wrench.

    They foam the tanks in the shell and include the fittings. Although it only have about 3/4" of foam on the nipple it sealed it in place better than epoxy.

    Here is the State WH

    http://www.statewaterheaters.com/lit/spec/res-gas/SRGSS02207.pdf
    http://www.stateind.com/lit/im/res-Gas/186589-001.pdf

    And American

    http://www.americanwaterheater.com/products/productDetails.aspx?ID=1038

    .
    William the Geezer, the sequel to Billy the Kid - Shoe



    Edited 9/14/2009 12:57 pm by BillHartmann

  8. User avater
    Jeff_Clarke | Sep 15, 2009 06:04am | #10

    I've used the A.O.  Smith 'powershot' water heaters (now Vertex line) quite a bit.   They're fine - but being powered for the vent they *do* lock out during a power failure.

    View Image
    Jeff

  9. mike585 | Sep 15, 2009 01:27pm | #11

    I have one. Replaced it once in 16 years. Never a problem with the direct vent. As I recall, I paid about $100 premium for the vent feature, which amounts to a blower and a pressure sensor. Pretty simple.
    I think it's Rheem.



    Edited 9/15/2009 6:29 am ET by mike585

    1. cameraman | Sep 15, 2009 03:01pm | #12

      I installed a 50 gal powervent AO Smith, direct vents threw PVC, about 11 years ago.

      Never ever!!ran out of hot water, runs flawless.

      Pd approx, $600. @ the supply house, only way to go.

      Take the bricks from your chimney and made a border around your wife flower bed with them, she will love it!!

  10. barmil | Sep 16, 2009 04:54am | #13

    If this is a chimney that has only provided for the furnace and the water heater in the past, then you're going to have the "orphaned" chimney syndrome in the winter if the water heater is the only thing venting into it. This will cause the water vapor to condense before it exits the chimney, leading to its deterioration. You could have a steel liner put into the chimney to prevent this. On the other hand, if you desire a direct venting water heater, you take the risk of no hot water if you lose electricity. This would be a problem in my earlier homes (Chicago area), but it hasn't been such where I currently live. I have gas for the stove and conventional water heater, and I think I could survive a blackout for some time with that and still enjoy a warm shower. My chimney also services a fireplace and the original furnace and water heater, so I had the liner installed when I went to a high efficiency gas furnace. I have a long time plumber who helps with my old house, so I let him put in a Bradford White water heater last time. I'm sure that there are less expensive alternatives, but at my age, something that lasts ten to twenty years might outlive me.

    1. User avater
      BillHartmann | Sep 16, 2009 04:57am | #14

      "On the other hand, if you desire a direct venting water heater, you take the risk of no hot water if you lose electricity. "My direct vent WH does not connect to any electrical power. Why would I not have HW if I lose electricity?.
      William the Geezer, the sequel to Billy the Kid - Shoe

      1. cameraman | Sep 16, 2009 03:42pm | #16

        Bill,

        My AO Smith needs elect. for ignition and blower for exhaust.

        No big concern to me, how often do you have a power outage?????

        Tank will keep water warm for a while, and I always have my NG stove to heat water if needed!

        1. User avater
          BillHartmann | Sep 16, 2009 06:45pm | #17

          What you have is a power vent. Different than a direct vent.Now it is not unusual to get an outage of less than a minute. When you are outside you can often hear the transformer hum when a squirrel tries for a cooked dinner.And the sub-station is about 1/2 mile away and you can often hear the reclosers (circuit breakers) try to close on shorted lines.For going out a couple of hours maybe every 2-3 years.For major outages of over 24 hours maybe every 10 years. Ice storms. And see seem to get power back before manny parts of the country..
          William the Geezer, the sequel to Billy the Kid - Shoe

          1. cameraman | Sep 16, 2009 07:04pm | #18

            "Now I see said the blind man to his deaf wife"

            I went back to reread the post and I assumed by getting rid of his chimney he wanted a power vent.

            What is the advantage of a direct vent over a power vent?

            I thought the power vents are more efficient!!

            Still lots of BTU's going out that direct vent pipe.

             

            I know the difference, my boiler is a direct vent and water heater a power vent.

          2. User avater
            BillHartmann | Sep 16, 2009 07:21pm | #19

            Well the direct vent usually outside combustion air, which is an energy saver. But I don't believe that is figured into the energy factor that the EPA uses.For a power vent the it might reduce heat losses during off times, but the amount probably depends on the details of installation.While there are versions with external combustion air, from looking at the catalogs most don't. And the basic difference in the power vents is that they blow enough excess air to keep it cool. So they might suck out a lot of conditioned air, again depending on the details of the installation.My direct vent has an energy factor of .62. And I believe that the highest gas tank type WH is .65. Saw those in the list, but you have to look up each model to find out what type it is..
            William the Geezer, the sequel to Billy the Kid - Shoe

          3. cameraman | Sep 16, 2009 07:36pm | #20

            AAHHH! Again!

            I  understand what you are saying.

            When outside by my vent, it does push a lot of air, conditioned air, even tho it's in a cooler basement.

            Now I have a Lenox forced air furnace, in another house,  that takes in combustion air from the outside!

            I am learning!

            Thank you!!!

      2. barmil | Sep 25, 2009 02:24am | #22

        My mistake. I misinterpreted your "direct vent" to mean assisted by some electrical source. Just recently considering the various options, I chose the old fashioned gas water heater venting up the flue over those which would require electricity to operate more fuel efficiently. If the power goes, I can still shower, use my gas stove, and call someone on my old-fashioned Princess phone.

  11. Jamie | Sep 16, 2009 05:04am | #15

    I don't think you have Menards in Jersey, but they carry them here in Iowa...

    Jamie

  12. DonCanDo | Sep 25, 2009 01:31am | #21

    Thanks for all of the input.  I just wasn't hearing enough rave reviews to convince me to replace a relatively new water heater with a direct vent type.

    One day I'd like to get rid of the chimney, but I'll wait until I do a bathroom remodel so I can make good use of the new-found space.

  13. User avater
    Matt | Sep 25, 2009 02:05pm | #24

    To me, direct vent is the only way to go as far as safety.  Little to no danger of backdrafting combustion gasses.  The only time we use conventional vented units is we have a tight budget.  OK - actually a really tight budget= electric :-). 

    Granted, I don't know anything about power vented models.  Where do they draw their combustion air from?

    When shopping, watch the efficiency ratings too... an EF rating of 57 would be minimal.  Some people don't realize it but a WH is one of the larger energy users in their home - because it more or less runs all the time.

    1. User avater
      BillHartmann | Sep 25, 2009 04:05pm | #26

      From what I have seen, most power vent's just draw internal combustion air. And it has to be more than a plain WH because they have to mix in enough air to cool the exhaust. But I have not idea how much.They do make sealed combustion units, with 2 pipes. By looking at the listings in the catalogs and how many models they have listed they don't appear to a common, but that is only a guess..
      William the Geezer, the sequel to Billy the Kid - Shoe

  14. martyrg | Sep 26, 2009 05:42am | #29

    I've had two of them over the last twenty-five years. The first one lasted 20 years running on propane. Only required normal maintenance. It was a Bradford White 40 gal. I replaced it with an A.O. Smith 50 gal. in 2004 when we switched to natural gas. It vents through 3" PVC to a large dryer vent - like fitting on the outside of the house. No problems to date. I'll buy another when the time comes.
    Marty

Log in or create an account to post a comment.

Sign up Log in

Become a member and get full access to FineHomebuilding.com

Video Shorts

Categories

  • Business
  • Code Questions
  • Construction Techniques
  • Energy, Heating & Insulation
  • General Discussion
  • Help/Work Wanted
  • Photo Gallery
  • Reader Classified
  • Tools for Home Building

Discussion Forum

Recent Posts and Replies

  • |
  • |
  • |
  • |
  • |
  • |
View More Create Post

Up Next

Video Shorts

Featured Story

Choosing the Right Construction Tape for the Job

Keeping out air and water for the long haul requires using seam and flashing tape the right way.

Featured Video

How to Install Cable Rail Around Wood-Post Corners

Use these tips to keep cables tight and straight for a professional-looking deck-railing job.

Related Stories

  • Keep Craft Alive Podcast: Ep. 19, Jesse Neumann, Arborist
  • FHB Podcast: Special Edition With Neil Freidberg of Louisiana Pacific and Kyle Stumpenhorst of RR Buildings
  • DeWalt Recalls 12-in. Sliding Compound Miter Saws
  • Podcast 483: Recalled Electrical Panels, Drainage Behind Brick, and Lazy Additions

Highlights

Fine Homebuilding All Access
Fine Homebuilding Podcast
Tool Tech
Plus, get an extra 20% off with code GIFT20

"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.

Get home building tips, offers, and expert advice in your inbox

Signing you up...

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
See all newsletters
See all newsletters

BOOKS, DVDs, & MERCH

Shop the Store
  • Pretty Good House
    Buy Now
  • Outdoor Projects
    Buy Now
  • Code Check Building 4th Edition
    Buy Now
  • 2021 Fine Homebuilding Archive
    Buy Now
  • Shop the Store

Fine Homebuilding Magazine

  • Issue 309 - Aug/Sept
    • 10 Steps to Install Crown Molding on Cabinets
    • How to Get Sturdy Walls Without OSB
    • Choosing the Right Construction Tape for the Job
  • Issue 308 - July 2022
    • Pretty Good House Book Excerpt: Copper Farmhouse
    • 10 Dos and Don'ts for Electric In-Floor Heat
    • A Sturdy Rail for Outdoor Stairs
  • Issue 307 - June 2022
    • How to Raise a Post-Frame Home
    • Trimming Deck Stairs
    • Evolving an Energy-Efficient Envelope
  • Issue 306 - April/May 2022
    • Framing Stairs to an Out-of-Level Landing
    • Building a Zero-Energy Home for Less
    • Good-Looking and Long-Lasting Traditional Gutters
  • Issue 305 - Feb/March 2022
    • The Steady Surge in Residential Solar
    • The Fine Homebuilding Interview: William B. Rose
    • How Good Is Your Air Barrier?

Fine Homebuilding

Follow

  • twitter
  • facebook
  • instagram
  • pinterest

Newsletter

Get home building tips, offers, and expert advice in your inbox

Signing you up...

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
See all newsletters
See all newsletters

Membership & Magazine

  • Online Archive
  • Start Free Trial
  • Magazine Subscription
  • Magazine Renewal
  • Gift a Subscription
  • Customer Support
  • Privacy Preferences

Taunton Network

  • Green Building Advisor
  • Fine Woodworking
  • Fine Gardening
  • Threads
  • About
  • Contact
  • Advertise
  • Careers
  • Copyright
  • Terms of Use
  • Site Map
  • Do not sell my information
  • Privacy Policy
  • Accessibility
  • California Privacy Rights

© 2022 The Taunton Press, Inc. All rights reserved.

X
X
This is a dialog window which overlays the main content of the page. The modal window is a 'site map' of the most critical areas of the site. Pressing the Escape (ESC) button will close the modal and bring you back to where you were on the page.

Main Menu

  • How-To
  • Design
  • Tools & Materials
  • Video
  • Blogs
  • Forum
  • Reader Projects
  • Magazine
  • Members
  • FHB House

Podcasts

  • FHB Podcast
  • ProTalk

Webinars

  • Upcoming and On-Demand

Account

  • Log In
  • Join

Podcasts

  • FHB Podcast
  • ProTalk

Webinars

  • Upcoming and On-Demand

Popular Topics

  • Kitchens
  • Business
  • Bedrooms
  • Roofs
  • Architecture and Design
  • Green Building
  • Decks
  • Framing
  • Safety
  • Remodeling
  • Bathrooms
  • Windows
  • Tilework
  • Ceilings
  • HVAC

Magazine

  • Current Issue
  • Past Issues
  • Magazine Index
  • Subscribe
  • Online Archive
  • Author Guidelines

All Access

  • Member Home
  • Start Free Trial
  • Gift Membership

Shop the Store

  • Books
  • DVDs
  • Taunton Workshops

More

  • FHB Ambassadors
  • Reader Projects
  • Podcast
  • Customer Support

Account

  • Log In
  • Join

Newsletter

Get home building tips, offers, and expert advice in your inbox

Signing you up...

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
See all newsletters
See all newsletters

Follow

  • twitter
  • facebook
  • instagram
  • pinterest

Join All Access

Become a member and get instant access to thousands of videos, how-tos, tool reviews, and design features.

Start Your Free Trial

Subscribe

FHB Magazine

Start your subscription today and save up to 70%

Subscribe

We hope you’ve enjoyed your free articles. To keep reading, become a member today.

Get complete site access to expert advice, how-to videos, Code Check, and more, plus the print magazine.

Start your FREE trial

Already a member? Log in