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boss1234
Jul 7, 2009, 01:43 PM
Hi,
We just purchased a home and we have 40 gallons of water heater which is 5 years old and after a shower or two water is cold. It's not that we take too much shower, but everybody in the house have to leave mostly same time in morning and this is not enough.:D
Here is the question -
If we install an new 60 or 75 gallon on top of the 40 gallons we have is a good idea? As my 40 gallon is working fine.

After few years when my 40 gallon will be out of order, can we just run 75 gallons with no extra cost and not replace anything in place of 40 gallons?

Everybody's answers and suggestions are welcome!

Perito
Jul 7, 2009, 02:03 PM
You might consider a tankless water heater.

boss1234
Jul 7, 2009, 02:03 PM
Help Please!


Not sure how effective is it when comes real cold winter! And flow running two or three showers same time?

Perito
Jul 7, 2009, 02:22 PM
A tankless water heater provides water on demand. You can get various capacities of tankless heaters (liters or gallons per minute), but you only warm the water you use. It seems to me that running two water heaters or a 75-gallon heater would be quite a waste of energy and probably very expensive. That's the reason for my suggestion.

letmetellu
Jul 7, 2009, 05:20 PM
If you have room for the second water heater I think that is a good idea. If possible I would connect them so that the 40 gallon heater supplied water to the 75 gallon heater, therefore the 40 gallon heater would be doing most of the work and when it went out the 75 gallon heater would be in good shape.

Also when you do the pipe fitting you could install them so that when the 40 gallon went out you could just turn a couple of stops and do away with the 40 gallon heater.

hkstroud
Jul 7, 2009, 06:23 PM
My opinion is that it is not worth the cost. You didn't say gas or electric. If gas you will have to run additional gas piping and flue. If electric you will have to run new circuit. That's in addition to the water piping you have to do. Cost you more to keep your existing 40 gal than its worth. In the mean time, turn up the thermostat.

boss1234
Jul 7, 2009, 08:07 PM
Thanks a lot for your all openion!
I have gas. Does keeping thermostat up will be the consumption of the same enery running two water heater?
Which tankless solution is the best - I mean the best product and how much it cost with installation. Who does the good job? I mean home depot or sears or elsewhere?
I really appreciate everybody's help!

rino13
Jul 8, 2009, 02:01 AM
Tankless is the way to go! They have units that will fit under the sink in the vanity.

Your tank stores 40 gal of hot water. Set in the middle your water temp it about 100 to 105 degrees. The average shower lasts about 10 minutes. The 1 gallon a minute of just hot water. While you are running the hot water out of the tank, the cold water is flowing in cooling off the hot water, so now the burner lights, or the heater (electric) turns on! Ever heat tap water on the stove? Know how long it takes to get hot enough for Tea or soup? Well this is what is going on in your water heater. Now think of 2 holes in the top of the pot, one letting out the hot water for washing, and the other letting in the same rate of tap water back in the pot to maintain the level in the pot, and the whole time the burner is on high! So after 2 showers the water is no longer hot, just warm. After the 3rd shower unless you wait for the water heater, someone is getting a cold shower! So for ease to figure, lets say your hot water is 100 degrees. After the first shower you water temp is on 94 degrees, After the third shower the water temp is now 88 degrees. The last person will start at about , and end at 84 if they are lucky. The longer the cold water runs the colder it gets. To help stop this have the children shower the night before, and the parents shower in the morning. Having a family of 7 and a 40 gallon heater too, that was the quick fix.

A tankless doesn't hold a reserve of hot water. It makes the tap water hot right now. So there in no inlet cooling effect. While your asleep, at work, at the game, visiting friends, out for dinner and a movie, or what ever the case may be, the hot water heater is not keeping a pot of water hot so when you want hot water you have it.

Tankless units come in 3 or 4 sizes for the whole house, and 2 or 3 local sizes! Tankless does cost more, but You'll recover the additional expense over the first year of operation. And tankless water heater qualify for the green energy credit!

boss1234
Jul 8, 2009, 09:08 AM
Thanks for the answer! What brand tankless are good? Also let me know what stores have better tankless option?


Also let me know about the price range if you have any idea.

dmrlook
Jul 9, 2009, 08:48 AM
Be careful if you go tankless - the venting requirements are quite different from your current gas heater. Make sure whoever you have install the heater knows what they are doing.

Milo Dolezal
Jul 9, 2009, 12:15 PM
You have to consider gas supply and venting issues with Tankless Heaters. Start up cost may be high but the benefits are great. Have a plumber to come over, see your place, and to give you ideas as to if it can be done or not.

However, 2 conventional heaters installed next to each other will present similar issues. If you install additional 75gln heater - you will have to run additional 4" vent or you can combine both vents (new and existing) and upgrade existing vent to accommodate Btu's for both heaters. ( I don't have the tables in front of me but I think it is either 5" or 6" vent you will need ). Also, gas line may need upgrade..

boss1234
Jul 9, 2009, 12:51 PM
Ok. Got it. Here's how I understood-
Tankless- Put x*2 amount of money as startup and get benefited later
Current + Another 75 gal - x*2 amount of money and mostly no benefit of energy
Replace current with 75 gal - x amount of money to install and no benefit of energy
Here is the scenario now- Current heater is not capable enough to run two shower and other household stuff at the same time. Or longer showers in Winter.(As we live in NJ and use lot of hot water while shower)
Tankless? Don't know how effectively it will give hot water while multiple chores going around in home.
Current + 75 - Sure not to run out of hot water again?
replace current with 75 gal?

Know what I mean?

Thanks

mygirlsdad77
Jul 9, 2009, 03:58 PM
Yep, I know what you mean. What size is your existing vent for 40 gal? I know its three inch of the water heater, but many time it will increase after water heater. If it increases to at least four inch, and no other gas appliences are connected to it,, I say replace the 40 with a 75. There is a huge difference between a 40 and 75. Not only storage capacity, but also BTU. If you replace the existing 40 with a 75, I almost guarantee you will have enough hot water for your needs. This would be the most cost effective route to go. Please let us know what you decide.

Lee

creahands
Jul 9, 2009, 04:11 PM
Replaced my 40 gal with 80 gal from sears.

Have not had hot water problem since change.

While my daughter was having house redone, had her and grandkids over every morn. 10 showers, 2 at a time in about 1 hr.

Check recovery time. It is different from company to company. Also units made by same company.

Chuck

Milo Dolezal
Jul 9, 2009, 04:24 PM
First, you should make sure you have Water Saving Shower Heads that use no more than 2.2 gln per minute. Same with other faucets in your house. Than, you get about 1/2 hour of continuous shower time out of single shower head. Also, select heater with fast recovery time. Install Thermo-Blanket on the heater and insulate your hot water pipes.

boss1234
Jan 28, 2010, 02:19 PM
First, you should make sure you have Water Saving Shower Heads that use no more than 2.2 gln per minute. Same with other faucets in your house. Than, you get about 1/2 hour of continuous shower time out of single shower head. Also, select heater with fast recovery time. Install Thermo-Blanket on the heater and insulate your hot water pipes.

During the winter, we tried insulate the hot water pipe, which helped. Now here is some numbers I got from additional quote from different people.

We have 6" vent which is enough for current 40 gallon water heater and gas heating system (furnace).

If I go 50 gallon water heater on top of the 40 existing, would the 6" vent be enough?

How is vertex heater - is that a new concept. One guy came and gave me almost a double price to have it installed then the rest of the guys.


Or to have a water storage system installed which stores heated water from furnace..!

Does anything sounds weird??


Thanks!

mygirlsdad77
Jan 28, 2010, 04:18 PM
Fifty gallon water heater usually only requires the same three inch vent as the 40 gallon, but some high recovery(higher btu) 50 gal heaters require a four inch. All depends on the BTU and vent specs on the boiler if the 6" pipe will work.

However, Depending on your boiler, the water storage system with boiler may be a good option for you. Cost a bit to install, as piping from boiler takes some time and knowhow, but if boiler is big enough to handle the load, you will have almost endless hot water.

speedball1
Jan 28, 2010, 06:17 PM
In addition to dmrlooks advice check the price of tankless water heaters. They can run quite pricey . I'm with Harold on this. Two water heaters can double the cost of both installation and maintenance. Good luck, Tom