Water heater advice...

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I need some general advice for a water heater purchase. I had a plumber recently come out to our home to have a look at our setup. We purchased our home a few months ago, began some renovations, and are now ready for a water heater to be installed soon.

First off, I'm still debating between direct vent, chimney vent and also a tank less water heater. The plumber that came out seems to be leaning towards a 50-gallon (or so) water tank with a mixing valve that with a power vent. I'm not so keen on the power vent because I can imagine it will be noisy. We do have a chimney nearby and I believe the current water heater is being vented through that. So, my first question is which way to vent is better? Is one more expensive than the other to install?

Our simultaneous water needs will normally be running showers (family of 4), possibly at the same time as a dishwasher and washing machine, then having enough hot water to fill a bath.

The plumber recommend a tank with a mixing valve on it.

Then, still looming out there as an option, is a tankless water heater. Our only concern with this is that it may not be able to handle the simultaneous tasks.

Thanks in advance for pointing me in the right direction...

I am not a professional so please bear with me.

If one has natural gas (a blessing), there must be concern shown for possible back-drafting, adequate combustion air supply and/or incomplete combustion (C0) of the gas-fired WH.

I am not sold on tank-less yet as they have a high initial cost and install (usually gas supply) and need venting also. It seems that most contractors do not know how to spec/install correctly and fix the problems afterwards.

Venting the WH to atmosphere via a masonry chimney can cause deterioration of the brick if not lined ($$$).

A WH with only a powered vent can insure no back-draft (CO). Additionally, one with an outside air source (Direct-Vent) ensures complete combustion.

Installing the vent(s) in the side-wall is no big deal if done correctly.

A 50 gal tank with a TMV should give you plenty. If it comes up short, a POU tank-less/tank will help on long draws.

I put a 50 gal electric in my daughter's home with 2 kids and a teenage daughter without a TMV (yet) and it does fine. Of course, your mileage may vary... :D
 
Are power vents very loud? The blower would be on constantly or would it be more like small intervals of time? How is the efficiency of a direct vent vs. power vent since power vent uses electricity?

The blower would only be operational as the WH is firing. You need to check if the manufacturer gives Sone Ratings in the specifics. Compare the sones given off as to your bath vent.
 
Thank you all for your replies. Still trying to wade through the varying views...

Just to reiterate, we have about an 1800-2000 sq. ft. home. 2 1/2 baths. On a day to day basis we will be using one shower (four people taking showers back to back normally). Our main concern is to have enough water to fill a bath after the showers. We might also run our dishwasher and washing machine simultaneously.

Many here seem to be against a tankless water heater. What are the main drawbacks of one? It seems that a tankless will have cold water sandwiches, a high initial cost, and possible more repairs to be done down the road?

If not a tankless water heater, what would the next best option be? Perhaps direct vent 50 gallon with a mixing valve? Or if not a mixing valve, a small tankless to create a hybrid setup? Just not sure at this point where to start...

I'm also trying to keep things efficient, but having enough hot water for the bath would be first priority and then efficiency...
 
I loved my tankless but most, if the power it out, you won't have hot water. Also, in a catastrophe, you will not have the much needed extra 50 gallons of potable water. I had a Navien with a built in recirc system, and about a gallon of stand by hot water so it prevented cold water sandwiching. Many say you need to flush the system yearly due to calcium build up, but I never did. This new house I installed a 50 gallon AO Smith, and it will be fine for many years to come with no maintenance at all. My tankless cost $1800, my tanked W/H cost me $750. There are pros and cons to both....
 
Thank you all for your replies. Still trying to wade through the varying views...

Many here seem to be against a tankless water heater. What are the main drawbacks of one? It seems that a tankless will have cold water sandwiches, a high initial cost, and possible more repairs to be done down the road?

I'm also trying to keep things efficient, but having enough hot water for the bath would be first priority and then efficiency...

A tank-less is the most efficient, period. But, the correct system and design (and manufacturer) has to be spec'd by a reputable contractor to gain the most from your initial investment. You also have to understand up front what is required regarding maintenance to keep the warranty in place.

Read This- http://www.profitableplumbing.com/tankless101.html

Take notes and maybe it will help in your decision.
 
[ame="https://www.youtube.com/watch?v=vffdymvjluk"]https://www.youtube.com/watch?v=vffdymvjluk[/ame]


look at energy efficiency

in my 35 years in the business humble opinion, the most efficient and cost saving system to install in a home, is a tank type gas water with a circulating system with all pipes insulated.


my question on tank less, why am i being paid to take out tank less i installed 5 years ago, and going back with the same damn tank w/h that was installed originally . makes you wonder doesn't it ?

http://www.waterheaterrescue.com/Longevity/tankless-water-heaters.html

tankless 1.jpg

tankless 2.jpg

tankless 3.jpg

tankless 4.jpg
 
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Do you think a 75 gallon tank direct vent tank (without a mixing valve) would provide enough hot water to get a family of four through showers and to fill a bathtub? If I do go tankless, is there a setup that could provide a backup tank if the power went out and also to help alleviate the cold water "sandwiches"?
 
We have 2 1/2 baths. Main entrance goes to the first floor. Powder room with sink on the first floor (only cold water to that room I believe). Kitchen on first floor. Basement contains a full bath (wouldn't be used too often) and laundry (gas dryer). Second floor has three bedrooms and the main/master bath. Bathtub and double vanity.

After viewing your video, I may want to be talked out of a tankless :) My main concern is so we will have enough hot water after showers to fill our tub. Probably my wife would be the only one to take a bath. Four of us would take showers prior to it probably.

I'd like to be as energy efficient as possible. So, that is why if we did go tankless, that I would opt not to have a mixing valve. In your opinion, does a mixing valve make sense?

Thank you...
 
no, a mixing valve does not make since, also, if you use a circ pump or a storage tank your wattanty is void on a tankless
my advice is no tankless, you will regret it later. but it is your choice

sounds like you are only using the full bath upstairs,

as your kids grow, they will start to use hot water [girls] like there is no tomorrow

I suggest you look into installing a 50 gallon upstairs, attic ? hall closet ?

from the basement can you see where the water pipes go to the 2nd floor ?


a 50 gallon down stairs for laundry/bath/kitchen

you reall need a 2nd bath upstairs, and whats up with no hot in the 1/2 bath,,,that would drive my wife nuts
you can buy a 200 dollar under counter insta hot to fix that



I wonder, sorry....tankless is not as efficient as a tank w/h the maintaince cost alone make it more expensive
 
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also, if you use a circ pump or a storage tank your warranty is void on a tankless

Unless the WH comes with an included cold water sandwich feature ...

Simply put, your need for a tank-less depends on several factors and cost(s) can be estimated on a spread sheet. In my particular case, I am on all electric and the cost of powering one would be expensive. If I were on NG, I would give it a lot of consideration.

It is simple. If you go tank and find later that you do not have the capacity, you could mount a remote tank-less and solve the performance problem(s) of a tank.

- http://www.chandlerdesignbuild.com/files/fhbDecJan08.pdf

- http://www.seisco.com/residential

There is no need/use of a TMV on a solely based tank WH.
 
The water heater would have to go in the basement. What do you mean by needing a second bath upstairs. We are renovating the home now and are having a powder room on our first floor and main bath upstairs. There will not be a full bath on the 1st floor. Just another full in the basement.

Given that the water heater will be installed in the basement, would you still be recommending a tank? If so, what type of tank and size? 75 gallon?

We are a family of four. Two boys. Now 8 and 11.

Thanks.
 
Personally, I think you are overthinking the water heater and size needed. With 4 persons, IMHO a 50 gallon water heater is more than adequate. I too had a family of 4 (with 2 teenage girls!) and never ran out of hot water, whether it was from the tanked or tankless water heater.

Sure you can install parallel 50 gallon tanked water heaters and install a recirc pump between them, but you will be spending big bucks for the install, and your monthly costs will skyrocket. With two boys, they will be in and out of the showers in 5 minutes, and won't use much water.
 
I loved my tankless but most, if the power it out, you won't have hot water. Also, in a catastrophe, you will not have the much needed extra 50 gallons of potable water. I had a Navien with a built in recirc system, and about a gallon of stand by hot water so it prevented cold water sandwiching. Many say you need to flush the system yearly due to calcium build up, but I never did. This new house I installed a 50 gallon AO Smith, and it will be fine for many years to come with no maintenance at all. My tankless cost $1800, my tanked W/H cost me $750. There are pros and cons to both....

Not to mention the constant servicing a tankless requires. Many HO's aren't aware of it and of course some installers don't either know or care to tell them.
 
add this to your spread sheet

tankless cost around $1000.00 on the front end more than a tank
and a minimum of $200.00 a year to maintain to keep the warranty
they only last 5 to 10 years
as opposed to a tank that lasts 15-20, so you have the replacement cost of another $2000.00
before the tank is wares out
 
i recomend a state 50 gallon gas water heater in the basement

if you can run a insulated circ line from the basement to the bath upstairs. that would help with effencey big time

have the pump controlled by the light switch in the bathroom...when light is on pump runs/ this saves a little also

or you can opt for an t stat strapped to the pipe, 5' away from the w/h
 
Installed a gas Rheem Fury in 2005 and is still operating flawlessly.
It vents up the chimney. Two adults and uses less than 20 cfm per month. If you have a well you nay have a problem with smelly hot water. That is solved by changing to a cathodic protection rod that is compatible with well water.
 

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