On demand electric water heater

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Muddytyres
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On demand electric water heater

Post by Muddytyres » Sun Feb 10, 2019 6:48 pm

We are thinking of replacing the standard electric water heater in our second (we are there on average 3-4 days a week) home with a tankless electric water heater. Has anyone had experience with them? The current tank is actually not large enough to fill the spa tub to above the jets (how crazy is that?) and I've always wondered how much $$ I waste with full time hot water in a part time house. Any specific problems/issues? It seems like it could potentially pay for itself in a short period of time given that it's only a part time home.
THANKS!

RetiredAL
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Re: On demand electric water heater

Post by RetiredAL » Sun Feb 10, 2019 10:27 pm

"Any specific problems/issues?"

Before you do anything, understand how much power is required. Get qualified help.

2.5 gpm @ 60 degrees rise will take approx 22KW, which is 92 amps. Can your service panel handle this additional amp load? To compare, your existing heater is likely 4500 watts, which is 19 amps of load.

If you have to replace your service entrance and power panel, you are going to see sticker shock.

The smallest I saw online is 11KW ( 46 amps), and it calls for a 60 amp breaker. GPM is directly related to power, so that power will only give you 1.25 gpm at 60 degrees rise.

Another uses 18KW. An even larger heater is 36KW and it called for 4 x 40amp circuits.

Where I worked before retiring, we had a couple of these that drew in the 50kw range. They ran on 460V 3-phase power.

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Epsilon Delta
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Re: On demand electric water heater

Post by Epsilon Delta » Mon Feb 11, 2019 1:37 am

Unless you have a very old or badly installed system standby losses are unlikely to be out of control.

In 2004 or so the Canadian standard for a typical 50gallon domestic electric tank was <80W or 640kWhr per year. Use your own electric rate but that's probably less that $100 per year. I remember the the Canadian standard because they directly measure these things instead of using EF*. I believe that Canadian and US tanks were in fact much the same.

* Which the DoE defines as "Trust us, you wouldn't understand the details".

It should be fairly easy to get significantly better, since those tanks were about R-12 and we insulate entire roofs to R-50. You also need to make sure the tank is inside the houses envelope, uses anti-syphon valves and insulate attached pipes for some distance away from the tank.

It's not clear if your aim is to save energy or fill the tub. If you want to fill the tub your best bet is to turn up the tanks thermostat and possibly add a mixing valve to prevent scalding. If you want to save energy cheaply you'd probably be better off with a super insulated storage tank than an instantaneous heater, but nobody will sell you that.

Trism
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Re: On demand electric water heater

Post by Trism » Mon Feb 11, 2019 5:53 am

The on-demand systems in my parents' house (built in 2014) are absolutely awful.

"On demand" means "turn on the water and wait 20 or 30 seconds for it to get hot," or "push the button under the sink, walk away, and come back later for 'instantly' hot water."

According to two different contractors who came over to assess, there aren't any logical places to put a traditional water heater that would be close enough to get hot water everywhere it's needed any more quickly (house is 3,300 SF sprawled out on one level)... so they don't really have any appealing options.

If you are satisfied with the performance of your current water heater I'd take a long pause before replacing it with a potentially inferior solution.

craimund
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Re: On demand electric water heater

Post by craimund » Mon Feb 11, 2019 6:11 am

Muddytyres wrote:
Sun Feb 10, 2019 6:48 pm
We are thinking of replacing the standard electric water heater in our second (we are there on average 3-4 days a week) home with a tankless electric water heater. Has anyone had experience with them? The current tank is actually not large enough to fill the spa tub to above the jets (how crazy is that?) and I've always wondered how much $$ I waste with full time hot water in a part time house. Any specific problems/issues? It seems like it could potentially pay for itself in a short period of time given that it's only a part time home.
THANKS!
I installed an electric on demand water heater (60 Amp) to replace a standard tank water heater. The unit services a full bathroom and kitchen. The unit works great for the kitchen and bathroom sink and the diswasher. However, the shower is only luke warm even if only hot water is used. Fortunately, the shower is rarely used.

In order to fill a tub with hot water in a decent amount of time using an electric on demand, you are going to need a large unit which consumes an enormous amount of power (120 amps or more). Not sure most electrical systems can handle this. May want to consider a propane/natural gas on demand heater. These can heat water much more rapidly and efficiently.

I shut off my tank water heater in the second home when not in use. Takes some time to heat up the water on return but saves on costs.
"When you ain't got nothing, you got nothing to lose"-Bob Dylan 1965. "When you think that you've lost everything, you find out you can always lose a little more"-Dylan 1997

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Muddytyres
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Re: On demand electric water heater

Post by Muddytyres » Mon Feb 11, 2019 6:53 am

To clarify- my current unit has thrown the breaker a few times recently (we come back and it's off). It's been pretty random of when it happens and I am worried it is going to fail.

retired recently
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Re: On demand electric water heater

Post by retired recently » Mon Feb 11, 2019 7:28 am

If you do not live there, why not flip the breaker and turn off the water heater when you leave? It only takes about 15 -20 minutes or so to heat the water I think? Surely you do not need hot water immediately when you return to the house after having been away for a few days?

wilked
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Re: On demand electric water heater

Post by wilked » Mon Feb 11, 2019 7:40 am

retired recently wrote:
Mon Feb 11, 2019 7:28 am
If you do not live there, why not flip the breaker and turn off the water heater when you leave? It only takes about 15 -20 minutes or so to heat the water I think? Surely you do not need hot water immediately when you return to the house after having been away for a few days?
The flip side would be meaningful also. Between visits turn everything off but the water heater. When you come back see how far the electric meter has moved. Take that number, divide by days, multiply by electricity cost and you’ll find out the cost to keep the water heater on standby. My guess is you’ll find it’s extremely low, and not a factor in the analysis you’re performing

brianH
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Re: On demand electric water heater

Post by brianH » Mon Feb 11, 2019 8:53 am

Tankless water heaters are highly overrated, in my opinion. Especially now with tank-based condensing gas or tank heat pump electric heaters equaling or beating the efficiency of tankless. About the only reason to consider one is for space constraints or the 'unlimited hot water' aspect, but if a tank unit is properly sized, it's unlikely that it won't be able to handle the need.

One thing many forgot to mention about tankless is the need for periodic (every 2 years) vinegar flushes to keep it running efficient. Sure, this can be a DIY job, but it's yet another thing to add to your list.

OldBallCoach
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Re: On demand electric water heater

Post by OldBallCoach » Mon Feb 11, 2019 9:09 am

I dont know if this will help you or not but when we built our new home ( retirement home ) we tried to be as energy efficient as possible..we did look into tankless gas units and after much debate ended up going with a highly rated 100 gallon gas hot water heater for the house and a tankless gas unit for the pool house. The unit in the pool house has been ok but there is the wasting of a lot of water while it comes up to temp at times. It is only three years old so I don't know much about problems yet. It IS really easy to winterise I will say however.. We are on natural gas so to us the question of gas vs electric really never came up. Best to you!

unstartable
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Re: On demand electric water heater

Post by unstartable » Mon Feb 11, 2019 9:14 am

My whole house is on a gas tankless that is 200,000 btu. It works great. We are not on a circulation system as water is plentiful and inexpensive where I live. It does take a few seconds longer than a tank water heater to come up to temp, but the difference is pretty small. Is there any chance you can go with gas or propane? In your situation I think I would just look at a larger tank water heater.

retired recently
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Re: On demand electric water heater

Post by retired recently » Mon Feb 11, 2019 9:24 am

wilked wrote:
Mon Feb 11, 2019 7:40 am
retired recently wrote:
Mon Feb 11, 2019 7:28 am
If you do not live there, why not flip the breaker and turn off the water heater when you leave? It only takes about 15 -20 minutes or so to heat the water I think? Surely you do not need hot water immediately when you return to the house after having been away for a few days?
The flip side would be meaningful also. Between visits turn everything off but the water heater. When you come back see how far the electric meter has moved. Take that number, divide by days, multiply by electricity cost and you’ll find out the cost to keep the water heater on standby. My guess is you’ll find it’s extremely low, and not a factor in the analysis you’re performing
I could easily be wrong on this but it was my understanding that if you were to shut off the water and leave the water heater on and if you had some sort of leak such that the water level in the heater drops it would burn out the elements and you would need to replace the water heater.

Agree that the cost of leaving on a regular water heater should be minimal. Presumably the type of heater that is 'on demand' would be more expensive as it circulates the water in the pipes and keeps it hot?

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ResearchMed
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Re: On demand electric water heater

Post by ResearchMed » Mon Feb 11, 2019 9:31 am

retired recently wrote:
Mon Feb 11, 2019 9:24 am
wilked wrote:
Mon Feb 11, 2019 7:40 am
retired recently wrote:
Mon Feb 11, 2019 7:28 am
If you do not live there, why not flip the breaker and turn off the water heater when you leave? It only takes about 15 -20 minutes or so to heat the water I think? Surely you do not need hot water immediately when you return to the house after having been away for a few days?
The flip side would be meaningful also. Between visits turn everything off but the water heater. When you come back see how far the electric meter has moved. Take that number, divide by days, multiply by electricity cost and you’ll find out the cost to keep the water heater on standby. My guess is you’ll find it’s extremely low, and not a factor in the analysis you’re performing
I could easily be wrong on this but it was my understanding that if you were to shut off the water and leave the water heater on and if you had some sort of leak such that the water level in the heater drops it would burn out the elements and you would need to replace the water heater.

Agree that the cost of leaving on a regular water heater should be minimal. Presumably the type of heater that is 'on demand' would be more expensive as it circulates the water in the pipes and keeps it hot?
Not all "on demand" circulate the water.
Ours just waits for a call for hot water, and then it starts flowing through the same pipes that the tank heater used to use, plus a few feet for where the new unit was installed. It takes about the same amount of time to feel the hot water as it did before. IF there is a difference, it's not noticeable.

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Re: On demand electric water heater

Post by TomatoTomahto » Mon Feb 11, 2019 9:33 am

If you have the room for it, I’d suggest a hybrid electric heat pump water heater. You can also add boosters to them in the unlikely event you need more hot water than it provides. You need a good amount of space because a) they’re large and b) they will cool the area around them as they heat water.
Okay, I get it; I won't be political or controversial. The Earth is flat.

retired recently
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Re: On demand electric water heater

Post by retired recently » Mon Feb 11, 2019 9:35 am

I must have misunderstood as I thought the whole benefit of an on demand system is the instant hot water...and I thought it achieved it by circulating it. On demand must be the type that only heats what you need, there is no reservoir of hot water. I worked as a dishwasher many years ago in high school and the restaurant had one that heated the water as you needed it but it did not work very well as the water was not that hot when we were using lots of hot water.

brianH
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Re: On demand electric water heater

Post by brianH » Mon Feb 11, 2019 10:06 am

retired recently wrote:
Mon Feb 11, 2019 9:35 am
I must have misunderstood as I thought the whole benefit of an on demand system is the instant hot water...and I thought it achieved it by circulating it. On demand must be the type that only heats what you need, there is no reservoir of hot water.
There are a couple of concepts at play here. This thread mostly seems to be talking about a single, centrally-located tankless water heaters. These units don't hold water at a temperature, but start rapidly heating the water flowing through them when a faucet is turned on. The downside of these is that you have a natural delay before hot water comes out of the unit plus all of the distance in pipes it needs to travel.

The second type, that I think you're referring to, are called 'point of use' water heaters. They are similar in concept to the central, on-demand units, but sit very near to the actual faucet (e.g. under the sink.) Because they are almost exclusively electric and small, they typically don't heat the water very hot, but you do get near instant warm water.

The other concept is a hot water recirculating pump. In most cases, a fixture near the end of the run has a special bridge valve that connects the hot side to the cold side to allow the pipes to form a loop. Another valve and pump near the water heater sends hot water down the hot line and gets semi-hot water back through the cold, which is reheated and cycles around. These work very well to keep hot water at the tap, but obviously waste a ton of energy to do so. Most of the time, there is a button or timer that only turns them on as needed.

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Re: On demand electric water heater

Post by Beach » Mon Feb 11, 2019 10:08 am

unstartable wrote:
Mon Feb 11, 2019 9:14 am
My whole house is on a gas tankless that is 200,000 btu. It works great. We are not on a circulation system as water is plentiful and inexpensive where I live. It does take a few seconds longer than a tank water heater to come up to temp, but the difference is pretty small. Is there any chance you can go with gas or propane? In your situation I think I would just look at a larger tank water heater.
Same here...love my tankless gas water heater. Will never go back to traditional again

unstartable
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Re: On demand electric water heater

Post by unstartable » Mon Feb 11, 2019 11:10 am

brianH wrote:
Mon Feb 11, 2019 10:06 am
The other concept is a hot water recirculating pump. In most cases, a fixture near the end of the run has a special bridge valve that connects the hot side to the cold side to allow the pipes to form a loop. Another valve and pump near the water heater sends hot water down the hot line and gets semi-hot water back through the cold, which is reheated and cycles around. These work very well to keep hot water at the tap, but obviously waste a ton of energy to do so. Most of the time, there is a button or timer that only turns them on as needed.
My understanding that the circulation concept is common in areas where water shortages are common. It is also probably more common in new construction if the system can be easily designed for it.

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Re: On demand electric water heater

Post by hicabob » Mon Feb 11, 2019 11:20 am

unstartable wrote:
Mon Feb 11, 2019 11:10 am
brianH wrote:
Mon Feb 11, 2019 10:06 am
The other concept is a hot water recirculating pump. In most cases, a fixture near the end of the run has a special bridge valve that connects the hot side to the cold side to allow the pipes to form a loop. Another valve and pump near the water heater sends hot water down the hot line and gets semi-hot water back through the cold, which is reheated and cycles around. These work very well to keep hot water at the tap, but obviously waste a ton of energy to do so. Most of the time, there is a button or timer that only turns them on as needed.
My understanding that the circulation concept is common in areas where water shortages are common. It is also probably more common in new construction if the system can be easily designed for it.
Hotels use hot water circulation too. They waste a lot of energy though since the hot water pipes have a lot of surface area and are kept hot at all times.

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Re: On demand electric water heater

Post by Thesaints » Mon Feb 11, 2019 12:48 pm

Thankless water heaters work fine, until you have an outage and have to take cold showers...

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Epsilon Delta
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Re: On demand electric water heater

Post by Epsilon Delta » Mon Feb 11, 2019 1:13 pm

Turning off the water heater, possibly using a timer, when he is away may not save much. When it's turned off the temperature of a typical tank drops by about 8 degrees C per day. The standby loss is directly proportional to the temperature difference between the tank and the environment, say 40 degrees C. Turning it off for one day saves about 10% of the standby losses for that day. Turning it off for 3.5 days saves about 25%* of the standby losses for that period. Turn it off for a year and you'll save 99% of the standby losses.

So it really depends on how he uses the house. If it's Tuesday, Thursday, Saturday and some Sundays turning off the tank only saves about 5% of standby losses (perhaps $5 per year) and is not worth it. If it's use Thursday or Friday til Sunday you perhaps triple the savings, but it's still marginal. If he uses the house the first to the fifteenth of each month that turning it off begins to be significant.

* You have to figure in the exponential decay of water temperature.

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Re: On demand electric water heater

Post by brianH » Mon Feb 11, 2019 1:19 pm

unstartable wrote:
Mon Feb 11, 2019 11:10 am
My understanding that the circulation concept is common in areas where water shortages are common. It is also probably more common in new construction if the system can be easily designed for it.
You certainly see it more in 'high-end' new construction or high-dollar renovations. It's one of those premium features that certainly makes life a little bit better, but has a pretty high operating cost.

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Re: On demand electric water heater

Post by mmcmonster » Mon Feb 11, 2019 1:29 pm

I have a Rinnai tankless water heater ( https://www.rinnai.us/tankless-water-heater ) that we installed while building our house. It heats via propane so it just needs a standard electrical outlet to work.

In any given room it takes ~ 3 seconds for hot water to come out of the faucet if it hasn't been used recently. I figure that's the amount of time it takes for water to get from the Rinnai to the faucet rather than an issue with heating the water.

A couple issues with tankless systems:
1 - If I lose electricity, I lose hot water immediately. While the system heats via propane, it requires an electrical system to turn the propane on and off.
2 - The water pressure is (apparently) slightly lower than a hot water tank. That's what my wife says. I've never noticed it.

The big benefits are:
1 - "Unlimited" hot water
2 - Lowered water heating costs as you are not heating water you are not about to use
3 - Smaller profile. Our unit is nailed into the wall of the foundation.

Like the system and have no problems with it so far (system is ~6 years old). Don't think I've had it cleaned yet. Should probably do that this summer.

ddurrett896
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Re: On demand electric water heater

Post by ddurrett896 » Mon Feb 11, 2019 2:08 pm

Muddytyres wrote:
Mon Feb 11, 2019 6:53 am
To clarify- my current unit has thrown the breaker a few times recently (we come back and it's off). It's been pretty random of when it happens and I am worried it is going to fail.
Mine was doing the same thing about 2 months ago. Bought a $50 rebuild kit from Ferguson (two elements and two thermostats) and a $15 element wrench. Problem solved.

Took maybe an hour to drain the tank and swap everything out.

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Epsilon Delta
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Re: On demand electric water heater

Post by Epsilon Delta » Mon Feb 11, 2019 2:15 pm

ddurrett896 wrote:
Mon Feb 11, 2019 2:08 pm
Muddytyres wrote:
Mon Feb 11, 2019 6:53 am
To clarify- my current unit has thrown the breaker a few times recently (we come back and it's off). It's been pretty random of when it happens and I am worried it is going to fail.
Mine was doing the same thing about 2 months ago. Bought a $50 rebuild kit from Ferguson (two elements and two thermostats) and a $15 element wrench. Problem solved.

Took maybe an hour to drain the tank and swap everything out.
I will add that a tripping breaker is not a mere nuisance. This is a safety issue and should be addressed. The problem is most likely in the water heater, but it could be in the breaker or the wiring.

LesBleus**
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Re: On demand electric water heater

Post by LesBleus** » Mon Feb 11, 2019 2:18 pm

I have the Eco 18 tankless water heater for my house which has 3 bathrooms and it came with the house build 7 years ago. I like it except for my master bath tub, which I do use often to wash the kids. During the winter which is now, on a cold day it may take a good 2 to 3 minutes for the water to get hot. So I'm wasting a lot water heating the bath tub. Luckily the showers gets hot fast. So overall it's not a bad system my electric bill is reasonable.

I think it's a good investment just don't expect it to be perfect.

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Re: On demand electric water heater

Post by miamivice » Mon Feb 11, 2019 2:19 pm

Muddytyres wrote:
Sun Feb 10, 2019 6:48 pm
We are thinking of replacing the standard electric water heater in our second (we are there on average 3-4 days a week) home with a tankless electric water heater. Has anyone had experience with them? The current tank is actually not large enough to fill the spa tub to above the jets (how crazy is that?) and I've always wondered how much $$ I waste with full time hot water in a part time house. Any specific problems/issues? It seems like it could potentially pay for itself in a short period of time given that it's only a part time home.
THANKS!
I read an article about these. They are not the cats meow. The issues they listed:

1. Water starts flowing right away but doesn't get warm for about 20 seconds. So you have 20 seconds of cold water every time you turn on the faucet. (This is different than a tank heater, where you have a delay to start but then hot right away until the water cools off.)

2. They don't producce a large volume of hot water, so it might be difficult for two devices to use hot water at the same time.

3. During a shower, if someone is using a facuet or diswasher is going, the water temperature might go up and down by 10 degrees which is annoying to the shower user.

4. They might require expensive wiring and/or vent upgrades because of their instantaneous energy consumption.

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Re: On demand electric water heater

Post by lthenderson » Mon Feb 11, 2019 2:33 pm

Muddytyres wrote:
Sun Feb 10, 2019 6:48 pm
It seems like it could potentially pay for itself in a short period of time given that it's only a part time home.
The biggest thing I see sales people "forget" to mention when selling tankless water heaters is their life expectancy. They have about the same life expectancy as a tank water heater so all those savings you get by not heating all the time go out the door when you have to replace your tankless water heater at five times the cost of it tanked brethren. The common response to that is that tankless will last longer if you take care of them and flush them regularly. Left unsaid is that the same thing applies to tank water heaters as well.

I've never seen the economics work out to justify a tankless water heater.

If your only reason for replacing it is to get something to fill up your jetted spa in one shot, consider a larger tank water heater.

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Re: On demand electric water heater

Post by inbox788 » Mon Feb 11, 2019 2:43 pm

Thesaints wrote:
Mon Feb 11, 2019 12:48 pm
Thankless water heaters work fine, until you have an outage and have to take cold showers...
We had a power outage for a week, and I was very surprised to discover I could still take hot showers with my gas water heater. Made the situation a little more tolerable. Without power or gas, the tankless won't work. One of the many tradeoffs going tankless.

Since OP is going electric tank to electric tankless, power is always going to be needed. Anyway, choose your location carefully. You want the heater as close as possible to where you're going to use the water (there will be longer delays getting hot water), but the noise is probably going to be worse, so you want that farther away.

Yeah, life expectancy for me for the tankless is half or less that of tank ones, so IMO, the costs should be doubled. You might save some power, but you'll likely use it to pay for earlier replacement, so mostly a wash.

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Epsilon Delta
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Re: On demand electric water heater

Post by Epsilon Delta » Mon Feb 11, 2019 3:05 pm

miamivice wrote:
Mon Feb 11, 2019 2:19 pm

3. During a shower, if someone is using a facuet or diswasher is going, the water temperature might go up and down by 10 degrees which is annoying to the shower user.
That won't happen with a modern (after about 1960?) pressure compensated mixing valve. These will vary the volume of the shower instead of the temperature. Still annoying, but not quite so annoying. And it avoids any risk of scalding.

So if this is happening to you one solution is to replace the shower mixing valve.

.

ddurrett896
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Re: On demand electric water heater

Post by ddurrett896 » Mon Feb 11, 2019 3:40 pm

Epsilon Delta wrote:
Mon Feb 11, 2019 2:15 pm
ddurrett896 wrote:
Mon Feb 11, 2019 2:08 pm
Muddytyres wrote:
Mon Feb 11, 2019 6:53 am
To clarify- my current unit has thrown the breaker a few times recently (we come back and it's off). It's been pretty random of when it happens and I am worried it is going to fail.
Mine was doing the same thing about 2 months ago. Bought a $50 rebuild kit from Ferguson (two elements and two thermostats) and a $15 element wrench. Problem solved.

Took maybe an hour to drain the tank and swap everything out.
I will add that a tripping breaker is not a mere nuisance. This is a safety issue and should be addressed. The problem is most likely in the water heater, but it could be in the breaker or the wiring.
The only thing inside the water heater are the Elements. Swap those with the thermostats and you have a new unit as long as the tank doesn’t leak.

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Re: On demand electric water heater

Post by MathWizard » Mon Feb 11, 2019 4:07 pm

unstartable wrote:
Mon Feb 11, 2019 11:10 am
brianH wrote:
Mon Feb 11, 2019 10:06 am
The other concept is a hot water recirculating pump. In most cases, a fixture near the end of the run has a special bridge valve that connects the hot side to the cold side to allow the pipes to form a loop. Another valve and pump near the water heater sends hot water down the hot line and gets semi-hot water back through the cold, which is reheated and cycles around. These work very well to keep hot water at the tap, but obviously waste a ton of energy to do so. Most of the time, there is a button or timer that only turns them on as needed.
My understanding that the circulation concept is common in areas where water shortages are common. It is also probably more common in new construction if the system can be easily designed for it.
Our kitchen is the furthest hot water faucet from the water heater. We would waste lots of water waiting to get
hot water.

I had an electrician wire in an outlet under the sink off of the switch for the light above the kitchen sink.
I installed a recirculating pump


When we do dishes, we turn the light on, and go around collecting any coffee cups. In just a few minutes, the
hot water is at the tap.

For hot water in a cup (hot cocoa or tea) we heat cold water in the microwave.

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Re: On demand electric water heater

Post by Rattlesnake » Mon Feb 11, 2019 4:31 pm

We have an electric tankless hot water heater at our cottage because of space constraints.... 100 amp service.... Works good but we don't do too many things at once because it'll pop the main breaker... For that reason I'm going to change it to propane this year....
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Re: On demand electric water heater

Post by 4nursebee » Mon Feb 11, 2019 4:32 pm

Love our Rinnai tankless propane since 2003!
Lots of misinformation here...
Lots to not worry about with tankless.
I recall electric is more efficient than the propane.
Will never go tanked in my house again.

Perhaps ask your plumber?
4nursebee

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lthenderson
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Location: Iowa

Re: On demand electric water heater

Post by lthenderson » Mon Feb 11, 2019 7:23 pm

Epsilon Delta wrote:
Mon Feb 11, 2019 3:05 pm

That won't happen with a modern (after about 1960?) pressure compensated mixing valve. These will vary the volume of the shower instead of the temperature. Still annoying, but not quite so annoying. And it avoids any risk of scalding.
When I redid our master bathroom, I put one of these in. Worth its weight in gold. It also has the ability of always being set to the same temperature so all I do is turn the water flow on and in about two seconds, the water is the same temperature it was at the end of my last shower.

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