New Gas Water Heater

[Jsmallberries]

Waiting for
Performance Platinum 40 Gal. Tall 12 Year 40,000 BTU ENERGY STAR Natural Gas Water Heater
1) Specs say it's a nominal 38 gallons? Where am I losing 2 gallons?

2) I'm in west central Florida, natural gas energy source. There are no expansion tanks installed around here, so it's safe to assume it's an open system? So none needed?

3)There is a pressure valve outside on a hose bib (see photo) probably good idea to replace with new install? Is this instead of expansion tank?

4) Is installing a straight 3/4 ball valve type drain recommended for future maintenance? What size fitting is needed, as threads are probably recessed

 

[Reach4]

Waiting for
Performance Platinum 40 Gal. Tall 12 Year 40,000 BTU ENERGY STAR Natural Gas Water Heater
1) Specs say it's a nominal 38 gallons? Where am I losing 2 gallons?

Not sure. I will say that newer WHs have more insulation than older ones, but I am not saying that is what is going on with your WH.

2) I'm in west central Florida, natural gas energy source. There are no expansion tanks installed around here, so it's safe to assume it's an open system? So none needed?

Given that you have the relief valve, that is uncertain whether systems there are open.

3)There is a pressure valve outside on a hose bib (see photo) probably good idea to replace with new install? Is this instead of expansion tank?

Yes, for the instead part, I think.

4) Is installing a straight 3/4 ball valve type drain recommended for future maintenance? What size fitting is needed, as threads are probably recessed

3/4 NPT brass nipple. A 2.5 inch, or maybe a 2 inch, would have been good for me, but I used 3.

They sell water heater rinser wands. A full-port ball valve would give full access. I have wondered if you could stick the wand from an electric pressure washer in there. I have not heard of anybody doing it.[/QUOTE]

 

[Sponsor]

 

[Jadnashua]

If your pressure relief valve regularly opens...do yourself a favor and install an expansion tank. There is a national push to add check valves to residential service water supplies, so if you don't currently have a closed system, you might, and then things will start to open to relieve the excess pressure. And, in the meantime, if it is closed, you'll be stressing every seal and hose in your home. The addition of a check valve, in theory, would help prevent your home from being a source of pollution to the rest of the system. Same idea as to why they require vacuum breakers on outdoor spigots...your hose could be sitting in muddy water with pesticides or oil contamination...with a hiccup in the system, it could get drawn back into the supply.

With gas fired WH, for awhile now, there has been a requirement to prevent that flame from igniting any flammable gas that might be in the area (paint fumes, gasoline fumes, etc.). As a result, when combined with the requirement to become more efficient, that added more insulation and height. It may be that the company was trying to keep the size (height) down, and as a result, lowered the capacity slightly. That's just speculation, I do not really know. But you will find the average, same capacity WH of today is taller than those before these new requirements became imposed.

 

[Jsmallberries]

TPR has never opened unless it's was for a test. The relief valve in the photo is common here instead of expansion tank
http://www.watts.com/pages/_products_details.asp?pid=803
set from 50 to 175 PSI to relieve system pressure, mounted to exterior hose bib, may be limited use in other parts of the country due to weather?

They have on my water bill a charge for a back flow fee, am I paying to add water back into the system, or paying for a back flow preventer?

As for the 40 gallon being a 38 gallon, received this from Rheem.

"The US government requires water heaters be labelled within "Families" of units. So a 38 gallon tank is labelled a 40 gallon water heater. We are sorry for any confusion this causes. You can get more information at energy.gov

Corporate double speak???, does this mean I will get less hot water, family of 4, Should I upgrade to a fifty

 

[Reach4]

may be limited use in other parts of the country due to weather?

Weather some places, water saving in others, I would think.

They have on my water bill a charge for a back flow fee, am I paying to add water back into the system, or paying for a back flow preventer?

I suggest asking the water department. Do you have an irrigation system?

does this mean I will get less hot water, family of 4, Should I upgrade to a fifty

I think so.

 

[Jsmallberries]

Irrigation but it is municipal reclaimed water, so no cross over possible

If they can legally advertise a 38 gallon as a 40, with no disclaimer, read the specs before buying. Jeez. Within families of units, at what point does a 30 something become a 40?

So if I go with a fifty gallon instead, will the added cost to maintain tank temperature with a slightly larger tank be noticeable, natural gas powered

 

[Reach4]

For the same shape, I would expect standby losses to be about 1.16 times as large for 50 as 40 and 1.2 times as large vs a 38. Those are based on presuming losses are proportional to surface area. I think losses would be less for a medium height tank vs a tall tank. But the tall tank saves floor space.

Is that noticeable? Not to most people, but you aren't most people.

 

[Jsmallberries]

Recurring theme with these is a problem with the flammable vapor sensor, can I get a gas hot water heater without that, trying to keep it simple without added features like FVS, electric venting,etc, just basic, any brand/model recommendations.

 

[Jadnashua]

The actual surface area of a cylinder as you increase the volume is not linear, so the hit for standby losses doesn't grow linearly. This is because of the r^2 factor. One common way to make a WH function as a larger one is to run it a bit hotter. Depending on where you live, a tempering valve may be required, and is highly recommended, regardless. This does raise the standby losses, but depending on your space heating needs...that extra heat does help the furnace or boiler when heat is on, so it's not 'lost'. If it's in an unheated area, the slight temperature rise can help with the dew point.

 

[MACPLUMB]

Irrigation but it is municipal reclaimed water, so no cross over possible

If they can legally advertise a 38 gallon as a 40, with no disclaimer, read the specs before buying. Jeez. Within families of units, at what point does a 30 something become a 40?

So if I go with a fifty gallon instead, will the added cost to maintain tank temperature with a slightly larger tank be noticeable, natural gas powered

Not unless you are counting pennies, on a one month billing cycle you are talking maybe about $5.oo
that is the reason behind the extra insulation

 

[Gary Swart]

If you are using the city water for you home and irrigation, you must have a back flow preventer to avoid cross contamination. I have no idea what reclaimed water is.

 

[Jsmallberries]

Reclaimed grey water or partially treated used for irrigation only, piped in separately.

So family of four, two bathrooms is 50 the way to go, and any recommendations, I would prefer a simple unit, less to go wrong.

 

[MACPLUMB]

If the the plus 2 are girls when they get to be teens you will need all the hot water that you can get, !
professional speaking I would diffidently go with the 50 every body taking showers and the dishwasher running,
then the washer starts that is how plumbers are taught to plan maximum load, not not minimum

 

[Jsmallberries]

Thanks,
I'm going to cancel the 40 and get a fifty.
I have an option for tall or short,the shorty is cheaper, it's a little wider, height difference is 50.5 versus 58.5
19.75 deep versus 23.75 for the shorty. Does the height/depth matter if you have the space for either??

 

[MACPLUMB]

No not really

 

[Jsmallberries]

Changed my questions as I learn more, here goes

I can get the energy efficient 50 gallon Rheem, 12 year warranty, brass drain valve and , the local gas co has a $400 rebate, but this unit requires electricity for pilot and vent, really wanted to keep it simple. No hot water w/o electricity

My biggest concern is the recurring threads in reviews about problems with the Flammable Vapor sensor

The 9 year warranty 50 gallon, no rebate, but no electric needed, and I don't see any recurring threads about FVS problems.

1)Do all new gas water heaters have this FVS, and can the Rheem FVS be re-set if it fails or will it need to be replaced

2) Is it better to forgo the added technology and rebate to get a more basic unit with less chance of future problems. Total saving with rebate will be $240 for getting the higher tech unit?

$17 dollar a year savings on "energy efficient" unit over the one that's not, that makes the difference on eligibility for the rebate WTF?????