Tankless Water Heater for Home???

Fabrik8 said:
I've thought about that, but it's useless during the 18 hours a day when we're sleeping or at work, and it's just a continuously running water cooler. Between the pump and the piping heat loss and the water heater cycling more often, it doesn't really make sense from an energy standpoint.
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Well, you could put it on a timer, so it only cycles say during the 2 hrs in the morning and 4 hrs in evening when it would be useful.
However, I just don't see the value aside form the sheer awesomeness of instant hot water. Can't see any way you wouldn't lose money on it, between the increased electric usage and increased HW usage.

This is one of those things that I personally think is good for keeping you trained on having a little patience - your daily forced moment of zen. So you have to wait 10 seconds for hot water to wash your hands... maybe slowing down for that 10 seconds is good for you. Kind of like everybody has lost attention span b/c we're now so used to being able to pop out a phone and check email/FB/NC4x4webz to pass 30 seconds in teh grocery line.

Or, if you're like me and keep the water too hot anyway then it works out perfectly b/c I just push the left valve all the way open and start washing, I finish just about the time it's too damn hot and yank my hands out. Since our bathroom sinks are the 2-valve type, instant hot water would actually be more work b/c I'd have to adjust 2 handles instead of just knocking one all the way open.
When I take a shower - routine is, I reach in and turn on the water, then get undressed, then jump in. No big deal.
 
RatLabGuy said:
When I take a shower - routine is, I reach in and turn on the water, then get undressed, then jump in. No big deal.
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Yep, I fire up the radio and let it pair with my phone, undress, water temp is good to go.

I'm actually thinking about integrating an audio system into the bathroom. Not one of those silly shower heads either, a real audio system.
 
Fabrik8 said:
I've thought about that, but it's useless during the 18 hours a day when we're sleeping or at work, and it's just a continuously running water cooler. Between the pump and the piping heat loss and the water heater cycling more often, it doesn't really make sense from an energy standpoint.
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I HAVE actually ran the load on that for a church. The cost came out to UNDER $7 a year running 24/7 with no aquastat.

Simple solution is to add an aquastat (if you have copper) to cut down on run times
 
Fabrik8 said:
I'm actually thinking about integrating an audio system into the bathroom. Not one of those silly shower heads either, a real audio system.
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I got excited, thinking THIS was one of those heads when I did a little water purification down in Honduras one year.

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Yeah....no, that was the source of hot water. Yes..that's an outlet it's loosely wired too.
 
Hey, at least they taped the wires to teh wall, I mean, you wouldn't want to have those things just dangling down.
 
Fabrik8 said:
I've thought about that, but it's useless during the 18 hours a day when we're sleeping or at work, and it's just a continuously running water cooler. Between the pump and the piping heat loss and the water heater cycling more often, it doesn't really make sense from an energy standpoint.
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Timer, dude. The pump is 120V.
 
catfishblues said:
Nest, dude. Pump kicks on when one of you is in the home. Nest outlets are getting cheaper every day. I want to get some just to play with.
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I already have a home controller. Wouldn't put a recirc pump on that, too unreliable.
 
shawn said:
I already have a home controller. Wouldn't put a recirc pump on that, too unreliable.
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It's a luxury item. The worst thing that could happen is a minor inconvenience, right? I think it would be the perfect thing to put on a controller. Your phone comes in range, it turns on. No dealing with programming a stupid timer, only to be caught on those odd days when you're home, but the timer is off. Besides, are the controllers really that much less reliable than 90% of the cheap-ass timers out there?
 
catfishblues said:
are the controllers really that much less reliable than 90% of the cheap-ass timers out there?
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Yes. And the timer is built into the pump.

And geofencing doesn't work at all.
 
catfishblues said:
. Besides, are the controllers really that much less reliable than 90% of the cheap-ass timers out there?
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YES!!

In fact, I've switched the last 2 homes I lived in from programmable thermostats back to honeywell dials. The gap between standard controls and BACnet LAN is HUGE and no one has filled it with anything remotely reliable or efficient. It's MUCH more efficient and cost effective to be consistent than it is to have to overcome initial load, in both HVAC and water heating.
 
CasterTroy said:
YES!!

In fact, I've switched the last 2 homes I lived in from programmable thermostats back to honeywell dials. The gap between standard controls and BACnet LAN is HUGE and no one has filled it with anything remotely reliable or efficient. It's MUCH more efficient and cost effective to be consistent than it is to have to overcome initial load, in both HVAC and water heating.
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You switched out programmable thermostats for you HVAC system to standard dial ones? I'm just curious why?
 
drkelly said:
You switched out programmable thermostats for you HVAC system to standard dial ones? I'm just curious why?
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OK, on design day (92.6° DB here) your cooling system will be doing all it can to maintain the desired indoor temp. MOST homes are fairly well insulated and rockin a decent R value. So lets say you have sufficient insulation and even have some shading on your southern exposure. If your programmable T-stat is set to ride higher in the summer when you're NOT there, and start trying to cool that house down at 4pm in anticipation for your arrival at 5:30, chances are your house is still going to be too hot for your comfort, and you're not going to be comfortable until the sun sets. It's only then your system is going to start "catching up" and your system is working as hard as it can to satisfy the thermostat.

Where as, if you allow your system to maintain all thruout the day, the system can cycle at intervals and ramp in stages (depending on your compressor/s)

The same with hot water. With a recirc HW system you are maintaining a constant temperature that the heater can easily maintain. Use a little at the sink? No problem, recovery isn't that big of a deal. Use a LOT? Well then the recovery takes longer, but overall your using a consistent amount of energy.

Think of it like an engine....drag race motor vs a generator. Which one will require more maint/replacement intervals?

I see this on a larger scale daily. Ex: WSFC schools programs all their systems to shut down at 5pm. Chiller goes offine, all the ERV's go into economizer modes. So June 10th when they're still in school and crank up the chiller at 6am, it takes till nearly NOON for the classrooms to cool down. We've advised for years to simply cut the temp up a few degrees instead of a system shutdown. Even ran the cost analysis for them....but this is what the school board has decided to do, and it costs them more money every month, and more maintenance.
 
Don't forget: every piece of anything in your house - every stud, every floorboard, every stick of furniture - is soaking up heat and humidity as the ambient temp and RH in the house rise during the unoccupied portion of the day. When you kick the setpoint back down to "occupied" mode, you have to take ALL that energy back out of the building.
 
Unlike the lights, cooling consistency is far from a myth. You obviously know more about it than someone like myself. I hear Mosley is looking for a good PE for their mechanical division....you should look into it
 
Okay, so for full disclosure and before this gets out of hand I'm obviously not a building professional. I know there are people here that know exactly what they're talking about, and I don't want to step on any toes (I'm good at that though). I like a good debate.

CasterTroy said:
You obviously know more about it than someone like myself. I hear Mosley is looking for a good PE for their mechanical division....you should look into it
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I know when I'm being messed with, and I'm being messed with. I'm pretty sure you're an expert in the field... And I'm pretty sure I'm not. :D
 
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Fabrik8 said:
That's like the myth that leaving fluorescent lights on is more energy efficient than turning them off when unoccupied, because of the energy required to start them up.
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And that whole myth was bastardized anyway.

There was a study done on the Sears tower in Chicago in the late 70s or early 80s. They determined that they saved money by leaving the lights burning around the clock, not because of the energy used to fire the lights, but they found bulb and ballast life were significantly reduced due to cycling. The savings in decreased bulb(lamp), ballast AND LABOR more than offset the increased energy consumption. But energy was cheaper then and lamps were more expensive.
 
Ron said:
And that whole myth was bastardized anyway.

There was a study done on the Sears tower in Chicago in the late 70s or early 80s. They determined that they saved money by leaving the lights burning around the clock, not because of the energy used to fire the lights, but they found bulb and ballast life were significantly reduced due to cycling. The savings in decreased bulb(lamp), ballast AND LABOR more than offset the increased energy consumption. But energy was cheaper then and lamps were more expensive.
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I've always loved that one. The startup current draw can be 4 to 5 times the normal operating current, but usually only lasts less than a second. After that sub-second time period, you're at normal operating current.
 
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Just purchased our first home, it was a complete gut and rebuild as well. We have a Rinnai and despite taking longer to get the hot water we like it. Im assuming the combination of being on the opposite side of the house and colder weather is the reason for that. Seems we could be wasting some water, not really sure what else we could do. We will see what out bill is now compared to summer time. Maybe itll offset
 
99JeepXJ said:
Just purchased our first home, it was a complete gut and rebuild as well. We have a Rinnai and despite taking longer to get the hot water we like it. Im assuming the combination of being on the opposite side of the house and colder weather is the reason for that. Seems we could be wasting some water, not really sure what else we could do. We will see what out bill is now compared to summer time. Maybe itll offset
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That is normal. The longer time to get hot water is just something you change your habits to deal with. For instance, if I plan on taking a shower. FIRST thing I do is turn the shower on full hot, then get a wash cloth and towel, take a piss, get undressed, maybe even lay out the clothes that I am going to wear etc, then get in the shower. I have not found it to be a big deal at all.
 
drkelly said:
That is normal. The longer time to get hot water is just something you change your habits to deal with. For instance, if I plan on taking a shower. FIRST thing I do is turn the shower on full hot, then get a wash cloth and towel, take a piss, get undressed, maybe even lay out the clothes that I am going to wear etc, then get in the shower. I have not found it to be a big deal at all.
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Bingo.
Except that I wait to piss in the shower, b/c that's what men do.
 
drkelly said:
That is normal. The longer time to get hot water is just something you change your habits to deal with. For instance, if I plan on taking a shower. FIRST thing I do is turn the shower on full hot, then get a wash cloth and towel, take a piss, get undressed, maybe even lay out the clothes that I am going to wear etc, then get in the shower. I have not found it to be a big deal at all.
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Yea thats pretty much what we do, doesnt bother me none but a cold nekked fiance is a little testy sometimes hahaha
 
On our rinnai there is something in the manual that tells you how to turn it up hotter then it will let you normally. Think there were some tiny switches inside.
Ours is set at 135 I believe.
 
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