Came Behind Experienced Inspector

[Brian A. MacNeish]

Originally Posted by wdecker

All this kind of stuff was around way before the "green" fad.


But the guy still had standard, conventionally vented water heaters, not the new 98+ tankless units.
Some things to think about.

Will, where did you get the figure?

From a 2006 American Council for an Energy Efficient Economy (ACEEE) study:

TanklessTechnology Basics

��Efficiency gains of 30% plus over storage water heaters
–Tankless.82 -.85 EF (Energy Factor)
–Storage .58 -.65

From a BC Hydro website:

Energy factors for gas tankless water heaters range from around 0.69 to 0.84, compared with 0.55 for a conventional tank and 0.86 for an ultra-efficient tank heater. Conventional electric tank water heaters have an energy factor of about 0.87 compared with 0.91 for an ultra-efficient tank and 0.98 for electric tankless water heaters.

[William J. Decker]

Originally Posted by Brian A. MacNeish

Will, where did you get the figure?

From a 2006 American Council for an Energy Efficient Economy (ACEEE) study:

TanklessTechnology Basics

��Efficiency gains of 30% plus over storage water heaters
–Tankless.82 -.85 EF (Energy Factor)
–Storage .58 -.65

From a BC Hydro website:

Energy factors for gas tankless water heaters range from around 0.69 to 0.84, compared with 0.55 for a conventional tank and 0.86 for an ultra-efficient tank heater. Conventional electric tank water heaters have an energy factor of about 0.87 compared with 0.91 for an ultra-efficient tank and 0.98 for electric tankless water heaters.

Saw it at a recent home show. PVC venting (intake and exhaust) with stainless steel heat exhanger. They offer a 20 year warranty, then, if you pay $200 and have 2 parts replaced, they extend the warranty for another 20 years.

See here for other info:

http://www.navienamerica.com/Navien%...Jan%202008.pdf

http://www.gotankless.com/tech_benefit_environment.htm

http://en.wikipedia.org/wiki/Water_heater Section 4.

http://www.tanklessmasters.com/savem...at=Environment

http://www.e-tankless.com/gas-vs-electric.php

http://www.phcnews.com/jan_08/products.php Fifth one down.

http://www.neo.ne.gov/neq_online/jul...lesswtrhtr.pdf

http://www.navien.com/jsps/boiler/main.jsp

http://www.stiebel-eltron-usa.com/

http://www.plumbersurplus.com/Prod/C.../39346/Cat/474

Hope this helps;

[Jae Williams]

Originally Posted by mcyr

Hell, no wonder he missed it, he was 73 years old.

.

Marcel

You got a problem with 73 years old???

[Brian A. MacNeish]

Originally Posted by wdecker

Hope this helps;

Will:

I only rely on ACEEE and GAMA info. They have no vested interest in the equipment!
http://www.aceee.org/consumerguide/waterheating.htm#lcc

Check footnote #4 for the chart in step 2:
4. Estimates for tankless gas water heaters are based on the federal EF rating method, which may over-estimate the efficiency of tankless water heaters in houses.



Another site discussing GAMA ratings (the independent true numbers):
http://www.sdreo.org/uploads/IWH_vs_CWH.pdf

Just did a search of GAMA instantaneous WH database, guess what....no Navien water heaters have been independently tested by them!!!!
http://gamapower.org/water_search.php?startpoint=30


From the Gotankless site, incorrect ( IMO, actually fraudulent) info to mislead the consumer:
Because of this inefficient process, a 60-gallon tank only has 45 gallons of useable hot water. The other 15 gallons are lost as cold water is added to the tank during the usage process.

Manufacturers always lie about their or their competitor's #'s in their favour.
A storage tank heater is rated on its "first hour" draw for how many gallons of actual hot water you can expect to get from it in the first hour from a fully heated tank. Most 40 gal (Imperial) electric tanks (with which I am familiar) can give 45-46 gallons of hot water in the first hour.
For inefficient gas storage tanks in the 75 gallon US range, the GAMA site says these tanks can gve 90-130 or so first hour gallons!!

[William J. Decker]

Originally Posted by Brian A. MacNeish

Will:

I only rely on ACEEE and GAMA info. They have no vested interest in the equipment!
http://www.aceee.org/consumerguide/waterheating.htm#lcc

Check footnote #4 for the chart in step 2:
4. Estimates for tankless gas water heaters are based on the federal EF rating method, which may over-estimate the efficiency of tankless water heaters in houses.



Another site discussing GAMA ratings (the independent true numbers):
http://www.sdreo.org/uploads/IWH_vs_CWH.pdf

Just did a search of GAMA instantaneous WH database, guess what....no Navien water heaters have been independently tested by them!!!!
http://gamapower.org/water_search.php?startpoint=30


From the Gotankless site, incorrect ( IMO, actually fraudulent) info to mislead the consumer:
Because of this inefficient process, a 60-gallon tank only has 45 gallons of useable hot water. The other 15 gallons are lost as cold water is added to the tank during the usage process.

Manufacturers always lie about their or their competitor's #'s in their favour.
A storage tank heater is rated on its "first hour" draw for how many gallons of actual hot water you can expect to get from it in the first hour from a fully heated tank. Most 40 gal (Imperial) electric tanks (with which I am familiar) can give 45-46 gallons of hot water in the first hour.
For inefficient gas storage tanks in the 75 gallon US range, the GAMA site says these tanks can gve 90-130 or so first hour gallons!!

In any case, my original point was that this architect went way overboard on some new, cussting edge technology (that was just bad and any jourmeyman could have shown this to him) while ignoring already proven energy efficiency techniques.

Green is still in the early stages and, mostly, a fad. Give it a couple of years and the real technology will start to become commonplace.