Looking for a small 200 M/L BR panel

[LarryFine]

I'm in the process of wiring a residential tankless water heater that uses four 40-a breakers, so I'm adding a second 200a M/L panel (no neutral) complete with second exterior 200a main and 400/320a meter upgrade.

Anyone know the smallest 200a M/L Eaton (Cutler-Hammer) type BR flush-mount indoor panel available? I'm looking for something in the 10- to 16-space range. I could make do with a redundant M/B if necessary.

 

[MyCleveland]

Just out of curiosity Larry, what is the expected savings over time for this type of heater compared to our old tank type ?

 

[user 100]

I'm in the process of wiring a residential tankless water heater that uses four 40-a breakers, so I'm adding a second 200a M/L panel (no neutral) complete with second exterior 200a main and 400/320a meter upgrade.

Anyone know the smallest 200a M/L Eaton (Cutler-Hammer) type BR flush-mount indoor panel available? I'm looking for something in the 10- to 16-space range. I could make do with a redundant M/B if necessary.

See the Eaton BR2040L200.

Out of curiosity , does it HAVE to be Eaton? Asking b/c there are some ML 200 siemens and and a few GE pmks that are 12's and 16's....

And ditto to MyClevelands question.

 

[LarryFine]

Out of curiosity , does it HAVE to be Eaton? Asking b/c there are some ML 200 siemens and and a few GE pmks that are 12's and 16's....

No, I just started there because that's the brand of the four existing breakers, but 2p breakers aren't very expensive. I appreciate the suggestion.

I have never explored the cost difference, but my guess is the four elements use four (or more) times the energy as compared to a one-element-at-a-time storage (tank) heater, but only during hot water demand.

A storage water heater has more loss due to maintaining temperature of a tankful of water during non-use time, but the real answer is probably that the more hot water used, the more the tank unit saves money.

 

[kwired]

No, I just started there because that's the brand of the four existing breakers, but 2p breakers aren't very expensive. I appreciate the suggestion.

I have never explored the cost difference, but my guess is the four elements use four (or more) times the energy as compared to a one-element-at-a-time storage (tank) heater, but only during hot water demand.

A storage water heater has more loss due to maintaining temperature of a tankful of water during non-use time, but the real answer is probably that the more hot water used, the more the tank unit saves money.

What people often overlook is the tank heaters are only inefficient during air conditioning season. Then their heat loss does add to the needed cooling load, but during heating season these loses lessen the necessary heating system load. So when you factor that into payback periods of using the allegedly "more efficient" water heating units it may not come out as favorable as some claim tankless water heaters are.

I had a HVAC guy once tell me he'd rather see a single 80 gallon water heater then two 50 gallon units when it comes to cooling load calculations - single 80 gallon loses less heat then two 50 gallon units. Though many plumbers often install two 50 gallon units over an 80 around here. I think they must cost less then a single 80, yet they would take more time and materials to install, plus what they need for electrical.

 

[growler]

What people often overlook is the tank heaters are only inefficient during air conditioning season. Then their heat loss does add to the needed cooling load, but during heating season these loses lessen the necessary heating system load. So when you factor that into payback periods of using the allegedly "more efficient" water heating units it may not come out as favorable as some claim tankless water heaters are.

I also doubt if these tankless units save as much as claimed. For each family depending on hot water useage it's going to be differrent.

 

[Coppersmith]

From reading the packages of various instant water heaters, they don't seem to raise the temperature enough for a nice hot shower unless you run the water really slow. Especially in colder climates where the ground water is colder than warm climates.

 

[kwired]

From reading the packages of various instant water heaters, they don't seem to raise the temperature enough for a nice hot shower unless you run the water really slow. Especially in colder climates where the ground water is colder than warm climates.

Which is why you find 30kw units. And flow is critical. too much flow and it will never be able to reach target temp, the water just isn't in the heater long enough.

With a typical storage tank style heater - the main control is at the bottom of the tank, it is much warmer then set point at the top of the tank. Set your unit to the max recommended of 125 and you still do get warmer water until you draw enough down.

With a instant water heater you don't get that excess temp, it never goes over setpoint by any significant amount, and only gets colder if flow is too high.

 

[Besoeker]

Anyone know the smallest 200a M/L Eaton (Cutler-Hammer) type BR flush-mount indoor panel available? I'm looking for something in the 10- to 16-space range. I could make do with a redundant M/B if necessary.

The Brit strikes again..........
M/L panel?

 

[kwired]

The Brit strikes again..........
M/L panel?

a circuit breaker panel that doesn't have a main breaker within - just "main lugs" on the bus(es).

The panel still requires overcurrent protection, but is usually at the point where the feeder begins.

 

[Besoeker]

a circuit breaker panel that doesn't have a main breaker within - just "main lugs" on the bus(es).

The panel still requires overcurrent protection, but is usually at the point where the feeder begins.

Appreciated, sir.

 

[texie]

I also doubt if these tankless units save as much as claimed. For each family depending on hot water useage it's going to be differrent.

I would agree. The proponents of instantaneous heaters, whether gas or electric, like brag that you are not wasting energy by not storing hot water in the tank. This argument fails to recognize that new tank type water heaters are so well insulated that these losses are minimal compared to older units. They also fail to consider the added capital cost of larger infrastructure required to heat water all at once, be it gas or electric.
And if you do electric tankless you better hope you don't get forced at some point into time of use or demand billing as now you can't shift your load use or control demand.

 

[curt swartz]

I own a house that that was vacant for over a year while working on a design and getting permits for a major remodel. The house had a basic 8 year old Sears 40 gallon water heater. I would stop by the house a couple times a week and usually wash my hand with warm water when there. The monthly gas bill was ~$4/month for use and standby loss. $3 of this was for taxes and distribution charges so the actual gas use was ~$1/month. I still pay $3/month even though the gas valve is off.

The sales pitch for tank-less water heaters saving $$$ because of no standby loss is 100% a scam. For gas water heaters the electronics in the heater probably cost more to run every month that the gas standby loss from a standard water heater..

 

[kwired]

I own a house that that was vacant for over a year while working on a design and getting permits for a major remodel. The house had a basic 8 year old Sears 40 gallon water heater. I would stop by the house a couple times a week and usually wash my hand with warm water when there. The monthly gas bill was ~$4/month for use and standby loss. $3 of this was for taxes and distribution charges so the actual gas use was ~$1/month. I still pay $3/month even though the gas valve is off.

The sales pitch for tank-less water heaters saving $$$ because of no standby loss is 100% a scam. For gas water heaters the electronics in the heater probably cost more to run every month that the gas standby loss from a standard water heater..

I wouldn't say a scam, just ignoring all the facts that contribute to true operating cost.

Electronics - they won't even draw a whole kW-hour in a month even at a really high electric energy rate will be less then 20 cents a month.

Refreshing tank heat even though no water was used is going to maybe use at least a few cents of gas every cycle it does this.

 

[retirede]

I would agree. The proponents of instantaneous heaters, whether gas or electric, like brag that you are not wasting energy by not storing hot water in the tank. This argument fails to recognize that new tank type water heaters are so well insulated that these losses are minimal compared to older units. They also fail to consider the added capital cost of larger infrastructure required to heat water all at once, be it gas or electric.
And if you do electric tankless you better hope you don't get forced at some point into time of use or demand billing as now you can't shift your load use or control demand.

To add: Some rural electric cooperatives will give a reduced rate if you let them control your water heater. During peak demand periods, they shut it off. With a conventional unit, the users rarely, if ever, realize it.
Obviously not a good idea with tankless.

 

[curt swartz]

I wouldn't say a scam, just ignoring all the facts that contribute to true operating cost.

Electronics - they won't even draw a whole kW-hour in a month even at a really high electric energy rate will be less then 20 cents a month.

Refreshing tank heat even though no water was used is going to maybe use at least a few cents of gas every cycle it does this.

In my opinion advertising substantial energy savings due to no standby losses is a scam.

No sure how you came up with less than 1kw a month. I just looked up a common model I see installed. It draws 5 watts in standby and 109 watts during operation.

 

[kwired]

In my opinion advertising substantial energy savings due to no standby losses is a scam.

No sure how you came up with less than 1kw a month. I just looked up a common model I see installed. It draws 5 watts in standby and 109 watts during operation.

5 watts or 5 VA in standby?

Still fairly insignificant compared to what it takes to heat the water though.

I'm guessing the 109 running watts includes a draft fan motor?

 

[brantmacga]

I’d be curious too what you end up saving with the electric tankless.

I’ve connected only one electric ever in a house, and it drew a constant 130A when running.


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[GoldDigger]

Which is why you find 30kw units. And flow is critical. too much flow and it will never be able to reach target temp, the water just isn't in the heater long enough.

With a typical storage tank style heater - the main control is at the bottom of the tank, it is much warmer then set point at the top of the tank. Set your unit to the max recommended of 125 and you still do get warmer water until you draw enough down.

With a instant water heater you don't get that excess temp, it never goes over setpoint by any significant amount, and only gets colder if flow is too high.

Some good points.
Many modern tankless contain a flow control valve which limits water flow to the volume that can be heated to the setpoint. That gives you, in effect, a low flow shower unless you mix in a lot of cold. And it means that when somebody opens another hot water tap the flow reduction is far more pronounced than it would be just from just the flow resistance of the pipes.

 

[norcal]

I’d be curious too what you end up saving with the electric tankless.

I’ve connected only one electric ever in a house, and it drew a constant 130A when running.


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As much as I hate propane if was going to install a tankless WH where there was no natural gas available would go propane, rather then a major increase of the service size. My tank type WH is close to 40 years old, doubt any tankless would last that long.