Shopping for tankless water heater & see e.g. Rheem offers both power
vent and direct vent.

Appears the DV models require a 5" stainless coaxial vent pipe . . .
more expensive and more complicated.

Does not appear the PV requires the coaxial pipe . . . piping outside
air for combustion is optional. So, simpler and cheaper I think?

Downside of PV is use of electricity for blower (when it's running)?
How much can that be? Enough to make the added $$ for the expensive
coaxial stainless worth it?

I am in West-central Ohio with 47-53 degree ground water.

I can sweat copper and run black pipe for gas . . . is vent piping a
"novice beware" job in your opinion?

thx
JR in OH

On May 2, 11:13=A0am, bari-old-dad  wrote:
> Shopping for tankless water heater & see e.g. Rheem offers both power
> vent and direct vent.
>
> Appears the DV models require a 5" stainless coaxial vent pipe . . .
> more expensive and more complicated.
>
> Does not appear the PV requires the coaxial pipe . . . piping outside
> air for combustion is optional. So, simpler and cheaper I think?
>
> Downside of PV is use of electricity for blower (when it's running)?
> How much can that be? Enough to make the added $$ for the expensive
> coaxial stainless worth it?
>
> I am in West-central Ohio with 47-53 degree ground water.
>
> I can sweat copper and run black pipe for gas . . . is vent piping a
> "novice beware" job in your opinion?
>
> thx
> JR in OH

Unless its a condensing unit double wall pipe may be code as it will
be hot, but I was cheap and lazy and didnt use it on my tankless. My
blower takes less than 100w if I remember, so figure out your time
used, and be sure to measure gas supply with a Manometer with all gas
apliances on and calculate in winter mains pressure reductions, or you
might hava cold shower next winter.

On May 2, 12:13=A0pm, bari-old-dad  wrote:
> Shopping for tankless water heater & see e.g. Rheem offers both power
> vent and direct vent.
>
> Appears the DV models require a 5" stainless coaxial vent pipe . . .
> more expensive and more complicated.
>
> Does not appear the PV requires the coaxial pipe . . . piping outside
> air for combustion is optional. So, simpler and cheaper I think?
>
> Downside of PV is use of electricity for blower (when it's running)?
> How much can that be? Enough to make the added $$ for the expensive
> coaxial stainless worth it?
>
> I am in West-central Ohio with 47-53 degree ground water.
>
> I can sweat copper and run black pipe for gas . . . is vent piping a
> "novice beware" job in your opinion?
>
> thx
> JR in OH

Big advantage of not needing electricity is that you have hot water
during a power failure. Maybe that's a big deal for you, maybe not. I
had a DV water heater (40-gal, not tankless) installed for this
reason.

I didn't know tankless heaters were available that don't need power.
What ignites the flame when you run the water?

Disadvantage is more expensive vent (as you've noticed) and much
tighter restrictions on length, height and bends in the vent, relative
to the power vent ones, which can be much further from your outside
wall. I had a plumber install mine so I can't comment on the DIY
issues.

Chip C
Toronto

On May 3, 11:26=A0am, Chip C  wrote:
> On May 2, 12:13=A0pm, bari-old-dad  wrote:
>
>
>
>
>
> > Shopping for tankless water heater & see e.g. Rheem offers both power
> > vent and direct vent.
>
> > Appears the DV models require a 5" stainless coaxial vent pipe . . .
> > more expensive and more complicated.
>
> > Does not appear the PV requires the coaxial pipe . . . piping outside
> > air for combustion is optional. So, simpler and cheaper I think?
>
> > Downside of PV is use of electricity for blower (when it's running)?
> > How much can that be? Enough to make the added $$ for the expensive
> > coaxial stainless worth it?
>
> > I am in West-central Ohio with 47-53 degree ground water.
>
> > I can sweat copper and run black pipe for gas . . . is vent piping a
> > "novice beware" job in your opinion?
>
> > thx
> > JR in OH
>
> Big advantage of not needing electricity is that you have hot water
> during a power failure. Maybe that's a big deal for you, maybe not. I
> had a DV water heater (40-gal, not tankless) installed for this
> reason.
>
> I didn't know tankless heaters were available that don't need power.
> What ignites the flame when you run the water?
>
> Disadvantage is more expensive vent (as you've noticed) and much
> tighter restrictions on length, height and bends in the vent, relative
> to the power vent ones, which can be much further from your outside
> wall. I had a plumber install mine so I can't comment on the DIY
> issues.
>
> Chip C
> Toronto- Hide quoted text -
>
> - Show quoted text -

My tankless uses 2 D cells for Piezo ignition, some have mini Hydro
generators that turn with water flow.

bari-old-dad wrote:
> Shopping for tankless water heater & see e.g. Rheem offers both power
> vent and direct vent.
> 
> Appears the DV models require a 5" stainless coaxial vent pipe . . .
> more expensive and more complicated.
> 
> Does not appear the PV requires the coaxial pipe . . . piping outside
> air for combustion is optional. So, simpler and cheaper I think?
> 
> Downside of PV is use of electricity for blower (when it's running)?
> How much can that be? Enough to make the added $$ for the expensive
> coaxial stainless worth it?
> 
> I am in West-central Ohio with 47-53 degree ground water.
> 
> I can sweat copper and run black pipe for gas . . . is vent piping a
> "novice beware" job in your opinion?
> 
> thx
> JR in OH

My State brand PV is 2.8amps on the dilution blower.  Exhaust temp is 
very low.  Vented through PVC.  A DYI job without problem.

On May 2, 12:13=EF=BF=BDpm, bari-old-dad  wrote:
> Shopping for tankless water heater & see e.g. Rheem offers both power
> vent and direct vent.
>
> Appears the DV models require a 5" stainless coaxial vent pipe . . .
> more expensive and more complicated.
>
> Does not appear the PV requires the coaxial pipe . . . piping outside
> air for combustion is optional. So, simpler and cheaper I think?
>
> Downside of PV is use of electricity for blower (when it's running)?
> How much can that be? Enough to make the added $$ for the expensive
> coaxial stainless worth it?
>
> I am in West-central Ohio with 47-53 degree ground water.
>
> I can sweat copper and run black pipe for gas . . . is vent piping a
> "novice beware" job in your opinion?
>
> thx
> JR in OH

Hey thankless have many downsides, with your low incoming water
temperature you might need 2 tankless in series to heat enough water.
Low flow may mean no hot water at all:( Plu buy a tankless with a
local knowledgable dealer they are more complex and will likely need
regular service, to remove hard water buildup.

standby loses of regular tanks are actually pretty low, you may not
save much and the payoff may be longer than the tanklesses useful
life...........

just some things to consider while spending large amount of money

DYI? Do Yourself In?

It sounds like the power vent is actually a bit simpler to 
install. Living in NYS, we do power cuts once a year or so. 
During the winter, a hot shower sure is nice. Well, it's 
nice during the summer, too. Remember, if you install the 
power vent model, you'll have no hot water while the power 
is off.

-- 
Christopher A. Young
Learn more about Jesus
  www.lds.org
.


"Steve Barker" <i...@hotmail.com> wrote in message 
news:9...@giganews.com...

My State brand PV is 2.8amps on the dilution blower. 
Exhaust temp is
very low.  Vented through PVC.  A DYI job without problem. 

On May 5, 6:11=A0am, "Stormin Mormon"
 wrote:
> DYI? Do Yourself In?
>
> It sounds like the power vent is actually a bit simpler to
> install. Living in NYS, we do power cuts once a year or so.
> During the winter, a hot shower sure is nice. Well, it's
> nice during the summer, too. Remember, if you install the
> power vent model, you'll have no hot water while the power
> is off.
>
> --
> Christopher A. Young
> Learn more about Jesus
> =A0www.lds.org
> .
>
> "Steve Barker"  wrote in message
>
> news:9...@giganews.com...
>
> My State brand PV is 2.8amps on the dilution blower.
> Exhaust temp is
> very low. =A0Vented through PVC. =A0A DYI job without problem.

You can have HW without electricity, you shouldnt of course as a rule.
Several times over the years while doing work ive made a mistake of un
plugging my tankless blower and forgetting to plug it back in, yes the
blower probably is not to code. I took a shower and realised my
mistake and went down to check Co on a digital meter and there was
none, I believe some gas still vented and the Co buildup wasnt great
enough for 5-6 minutes of runninng to register anything on peak level.

Stormin Mormon wrote:
> DYI? Do Yourself In?
> 
> It sounds like the power vent is actually a bit simpler to 
> install. Living in NYS, we do power cuts once a year or so. 
> During the winter, a hot shower sure is nice. Well, it's 
> nice during the summer, too. Remember, if you install the 
> power vent model, you'll have no hot water while the power 
> is off.
> 

I'm still not seeing what is going to happen to the 40 or 50 gallons of 
hot water that are in the tank.  And also,  who the hell wants to shower 
in the dark?  This argument that you won't have hot water in a power 
failure just doesn't hold water.  

On May 5, 8:18=EF=BF=BDam, Steve Barker  wrote:
> Stormin Mormon wrote:
> > DYI? Do Yourself In?
>
> > It sounds like the power vent is actually a bit simpler to
> > install. Living in NYS, we do power cuts once a year or so.
> > During the winter, a hot shower sure is nice. Well, it's
> > nice during the summer, too. Remember, if you install the
> > power vent model, you'll have no hot water while the power
> > is off.
>
> I'm still not seeing what is going to happen to the 40 or 50 gallons of
> hot water that are in the tank. =EF=BF=BDAnd also, =EF=BF=BDwho the hell =
wants to shower
> in the dark? =EF=BF=BDThis argument that you won't have hot water in a po=
wer
> failure just doesn't hold water. =EF=BF=BD

A TANKLESS HAS NO WATER IN THE TANK!! Because there is NO TANK!

over the years we have had power failures including a memorable 3 day
one. some nearby were off over a week:(

you can run a garden hose thru your home, snaking it around ending at
tub to provide minimal warmth espically valuable in the winter.

our tank is 75,000 BTU just a tad less than our furnace.