I got this email from a QA program manager. Looking for feedback. Thanks

 

 

I have a question for you I'm hoping you can shed some light on.

How are we supposed to proceed with getting combustion and worst case depressurization numbers from an area that is inaccessible?

I just ran into this situation over at customer's home with a tankless water heater on his second floor.
The only option to get a flue gas sample is to set up an extension ladder in an alley which doesn't have clearances that are proper for an extension ladder.

Look forward to hearing how you would proceed on this.

Views: 73

Replies to This Discussion

 

You should be able to access the room where the water heater itself is located.  Otherwise if it is in some kind of sealed off space, then it probably doesn't meet code requirements.  So you should be able to do a worst case depressurization test on the CAZ.  Although since it is sealed combustion, it is probably not a big deal. 

 

I think a lot of programs will waive requirements to get a CO reading on the flue gases if the appliance is condensing and/or sealed combustion, and the flue vents out the roof and is not easily accessible. 

 

I'd agree w/ the previous post. When going for a worst case test, you only need to measure presssure difference in the CAZ WRT outside. I'm figuring you can get into the CAZ. If required, Measuring exhaust gas for CO and efficiency on a sealed appliance is done from the outside according to most, though several well known pro's will drill the PVC pipe and sample from there, then seal the pipe with fire rated caulk.   
Thanks folks. The culprit here is an older tankless that is not sealed combustion.

If the tankless water heater is not sealed combustion, then it could be either power vented (one PVC pipe), induced draft (inducer motor and metal pipe), or natural draft (with draft hood).  I am not comfortable drilling a PVC pipe to measure CO, but some will drill it and seal it with silicone caulk.  A metal pipe for an induced draft appliance can be drilled and plugged with a metal plug or taped with metal tape.  If it is natural draft, you can measure the CO by putting the probe down in the heat exchanger from the draft hood.

This is what we do:  The Standards are clear:  No air sealing, dense packing more than 15% of the shell area, duct sealing outside the thermal envelope, if you cannot complete the or combustion testing protocol.  So, if we cannot test all the appliances that might be affected by modified house pressures due to air sealing, than we don't recommend air sealing.  More accurately, we explain the issues on the work order and customer report.  If we get full access to the entire building, so we can create worst case conditions in all CAZ's, and we can test to the Standards, then we include air sealing on the work order (if apporpriate).   Also... yes, we've climbed ladders to take samples from flue gasses... but of course we prefer to drill and fill where allowed!

RSS

Latest Activity

Brett Little posted events
yesterday
Ben Thompson replied to Stuart Perkin's discussion TrueFlow in the group Energy Auditing Equipment for Sale, Trade or to Purchase
"Hi Stephen. Do you still have a Trueflow that you would sell? Ben Thompson,…"
Friday
Ben Thompson replied to Landon's discussion WANTED: Blower door complete set Retrotec or Minneapolis in the group Energy Auditing Equipment for Sale, Trade or to Purchase
"Hi Landon. I have a Minneapolis blower door set-up that I would like to sell. It's in…"
Friday
Ben Thompson added a discussion to the group Energy Auditing Equipment for Sale, Trade or to Purchase
Thumbnail

Wanted: TrueFlow plate

Seeking an Energy Conservatory TrueFlow plate (grid) in good condition. Ben Thompson.…See More
Friday
Scott Partlo replied to Jerry Needham's discussion Closed cell on roof deck to prevent mold.
"You say that 2" of closed cell foam is applied OVER the roof deck.  Where exactly was the…"
Friday
ayazfudugo1 replied to Tom Smith's discussion Are Energy Efficient Windows worth the investment?
"For both new and existing homes, Energy efficient windows are an important consideration Heat…"
Friday
Profile IconTodd Williams and Haley Keegan joined Diane Chojnowski's group
Thumbnail

Hall of Shame

In this group, members share an array of images from the field, showing the kinds of issues…See More
Friday
Todd Williams liked Diane Chojnowski's group Hall of Shame
Friday
Home Energy Magazine posted a blog post
Thursday
Leona Zoey posted a blog post

Landlords Are Your Friends

While it may be easy to forget given their apparent position of power over you, landlords usually…See More
Thursday
Haley Keegan joined Building Performance Institute's group
Thumbnail

Building Performance Institute (BPI)

BPI is the nation's premier standards development, quality assurance and credentialing organization…See More
Thursday
Donald Hester replied to Jerry Needham's discussion Closed cell on roof deck to prevent mold.
"For the roof shingle issue that is an unfortunate issue with many home inspectors that have been…"
Thursday
Profile IconJason Green, Dennis Smith, Alex Ortega and 2 more joined Home Energy Pros Forum
Thursday
tedkidd replied to Quinn Korzeniecki's discussion BPI CEO Larry Zarker's Review of "The Home Comfort Book" in Healthy Indoors Magazine in the group Building Performance Institute (BPI)
"...free chapters of book available here - http://bit.ly/HPchapterlist"
Thursday
tedkidd liked Quinn Korzeniecki's discussion BPI CEO Larry Zarker's Review of "The Home Comfort Book" in Healthy Indoors Magazine
Thursday
William Collins's video was featured

Foam Kits vs. Spray Sealants Gun

How does the Foam Kit stack up to the Spray Sealants Gun when it comes to simplicity? When you integrate the Spray Sealants Gun to a 16lb Canister, you creat...
Thursday
Scott Becnel added a discussion to the group Energy Auditing Equipment for Sale, Trade or to Purchase
Thumbnail

Brand new DucTester at a discount

Brand new DucTester at a discountI have a brand new 300 DucTester system from Retrotec for sale at…See More
Wednesday
Scott Becnel joined allen p tanner's group
Thumbnail

Energy Auditing Equipment for Sale, Trade or to Purchase

Discuss the pros and cons of the equipment you are interested in prior to purchase. Post equipment…See More
Wednesday
Lucyna de Barbaro liked Home Energy Magazine's blog post AeroBarrier: The Silver Bullet to Zero Energy Affordability, by Paul Springer
Wednesday

Photos

  • Add Photos
  • View All

© 2018   Created by Home Performance Coalition (HPC)   Powered by

Badges  |  Report an Issue  |  Terms of Service