So the dip**** hasn't come forth with the answers yet?
May I refer you again to posts #127-129
Let me see now. I have 1 full bath and two half baths. How do I supply two showers running at the same time?
Do I really have to give you that answer? The answer is obvious!
Simple. Turn on the tap. Press the On button. Turn the cycle knob? You can easily take a shower and use all the hot water taps at the fixtures at the same time.
Heck even if I did a hot water wash at "the same time" that I wanted to take a shower, by the time I got into the shower the washer tub would be full of hot water. Needless to say, who does a "hot" water wash and rinse these days. I prefer to spend my money in different way that pissing it down the drain!
Costs to do a load of laundry. The electric rate used in these calculations is 1/2 of what I pay ($.206 per kWh) and the gas is light a bit also ($1.63 per therm).
Dang fruit flies buzzin around...
Can you hear them?
Laddy Boy, once again I direct you to comments you need to nake on posts #127-129 in this thread.
Straight Talk About "On-Demand Tankless Water Heaters by A.O. Smith applies to you and to others that fall under this part. I put the part I am taling about in bold.
Q. What are the best applications for on-demand tankless water heaters? In other words, when is tankless the best choice?
A. This is another multi-part answer…
- Residential New Construction. Installation of tankless heaters is less of a problem here, since the necessary venting, gas lines and other tankless requirements can be built into the plans for the home.
- However, because most builders want to keep the cost of their homes as low as possible, the initial price of tankless water heaters will be a significant obstacle. We don’t see on-demand tankless as a saleable proposition for residential new construction, except for high-end custom homes, where the builder and/or homeowner can handle the expense of installing multiple tankless units.
- Residential “Repair and Replacement”. We’ve already discussed the high cost of purchasing and installing an on-demand tankless water heater to replace an existing tank-type heater. In our view, most homeowners have been and will continue to be satisfied with the performance of a tank-type water heater. It is likely that the “downstream” claims of tankless manufacturers will persuade most consumers to pay extra for a technology that is not really in tune with American lifestyles.
- Residential Remodeling. This is the primary niche for on-demand tankless water heaters, and particularly for the A.O. Smith ProStar model XT19400. ProStar should be positioned as a point-of-use water heater serving low to medium demand applications or individual fixtures, or as a supplemental hot water source to the home’s primary tank-type water heater for room additions and other major kitchen or bath remodeling projects that significantly increase hot water demand. ProStar should only be considered as a “whole house” water heating option for very small homes or apartments with low hot water demand.
Yes, but according to the plumbing instructor you are ignoring "the code".
By the way, the description of a "very small home" has changed over the years. My modest size home 3 bedroom home has 2,400 sq ft of space including the first floor level garage. The McMansions that they have built in recent years are nice, but one needs a nice income to afford them. I wonder how many of those home "owners" are underwater (or worse)?
"Dude, we can fix that. My old man is a TV repairman, he's got the ultimate set of tools!" --Jeff Spicoli
I'm not against tankless heaters (I may go tankless myself next time due to severe space restrictions) but I do have a question on your numbers.
You mentioned that your system is rated at 2.09 GPM output at, I believe, 75 degree temp rise and you have also stated that you can run multiple showers at the same time.
That doesn't seem to add up and I'm wondering how you achieve this? Given that a low flow showerhead is rated at a higher GPM that the unit, how can you run two at once?
The only thing I can think of is that each shower uses some cold and some hot so you might be able to squeak by with two running but it still doesn't seem quite right, particularly for those who might like hot showers.
Also, how do you find it works when you have someone in the shower and a sink calls for hot water on full? (filling sink to do dishes, for example) Is it able to keep up?
your tankwortless will only supply 2.09gpm flow rate
So you have already posted that your tankworthless will NOT supply more then 1 shower at a time
DIY Handyman (not 4 hire)
I have enough to do to my own house
The "boys" have stated over and over again that I can not run two showers "at the same time". I never made that claim. I have never even tested for that type of use. My home has one full bath and two 1/2 baths (read post 191), so how can I even test for that type of use when I only have one shower?
Getting back to the basic question, the code limit for shower heads in this state is 2.5 GPM. If you use multiple shower heads in one shower stall, the total flow of all the shower heads added together can not exceed 2.5 gpm.
I have the water heater thermostat set to 120 degrees. With 40 degree incoming water temperature, the specified 90 degree temperature rise @ the rated 2.09 GPM would indicate a limit of 130 degrees @ 2.09 gpm. In the summer with warmer incoming water temperatures, the unit is rated at 4.18 gpm with a 45 degree temperature rise.
Anyhow, the first time I even measured flow in my shower was this year. I have the older three handle (hot / cold /shower) setup in my bathroom, so it was easy to measure hot and cold volume at the end of a long shower. As I recall the ratio was about 2 units of hot water to 1 unit of cold water (@ 40 degrees). The usual flow rate was about 1.5 gpm as I recall, so that would be 1 gpm hot water and .5 gpm of cold water. I have tested at full volume so the shower head was the volume limiter, so that would be about 1.6 gpm hot to .8 gpm cold.
Hot water capacity @ 120 degrees (40 degree incoming) from any other fixture is available @ about .5 gpm to 1 gpm. That temperature is hot, so you end up mixing cold in with hot water use at any specific fixture.
I have never had anyone try to fill up the kitchen sink with hot water while anyone was taking a shower. I use a dishwasher. To tell you the truth I am not even sure where I put the drain plug for the garbage disposer.
Full on at the kitchen sink is 1 gpm (1 gpm maximum hot and cold mix). The normal comfortable setting is in the middle of the single handle kitchen fawcett (about 1/2 hot and 1/2 cold).
Now if I turn on every hot water fixture to full on and leave them there, the hot water temperature in the shower will not remain at 120 degrees. Not sure of how low it goes either because that scenario has never happened to me in my lifetime. Maybe I will measure that this week if I get a chance to do so.
Make sure you check you incoming winter water temperature and water pressure before you consider tankless gas. Tankless electric is another animal altogether and is not recommended for a lot of valid reasons.
A.O. Smith, Bradford White, Rheem, and State water heater manufactures all say the same thing that Tankless water heaters is not the cure all that everyone is making them out to be.
I have installed many tankless units, some of the home owners listened and let me properly size the unit and if the need be install two units together to meet their demands.
The others that insisted from all their "research" that a single unit will handle their needs I still installed it for them with a disclaimer that I had informed them of a properly designed system. Sure enough after a week I get a call telling me that they are only getting tempered water. I just tell them to read my disclaimer, and if they want me to come and install it the way I recommended to them in the first place I be more than happy to. Other than that I can not help them any further.