Eliminating Heating Coil On Boiler.

Chamkila

Hi Guys, I have a burnham boiler oil fed, (Just bought the house) I want to add a electric heating tank. I know how to wire it up and all just dont know how to eliminate the heating coil. And how to turn it off so the boiler wont turn back on when it senses that the heating coil is low on water since it wont be having any water in it. I dont have natural gas coming into my house thats why i`m going with electric.

I want to add this hot water heater from home depot.





I`m gonna run 8/3 wire with a 50 am 220 dual breaker. But i just dont know what to do with the plumbing. All the help will be appreciated. If I am not clear enough please let me know i`ll try to explain it more.

SWEI

Chamkila said:

I want to add this hot water heater from home depot.
...
I'm gonna run 8/3 wire with a 50 am 220 dual breaker.

I don't see a link or a photo of the heater in question, but a 50A circuit can deliver 9,600 Watts, which is quite a bit more than most residential tanks need. Side note: A 50A breaker requires either #8 THHN (in conduit) or #6 NM cable. You only need two hots (no neutral.)

You can pipe an electric tank heater as a buffer tank which will greatly boost your first hour capacity over the tankless coil alone. It can still use one of the electric elements as a booster or for backup.

Robert O'Brien

Has to be Long Island with the dual aquastat! You may want to think twice with 23c Kwh

lchmb

but to answer your question, the aquastat on the coil has 3 settings. Turn the low limit to zero and that will shut of the low temp of the boiler...but keep in mind, if the boiler has been hot all it's life it could end up leaking if it goes cold......that is as long as the boiler is wired t-t off the taco box...have seen plenty where they jump the aquastat out to maintain high temp...

Hilly

And this should be where @icesailor jumps in with his 'sidearm water heater'. Unless the oil has to go I would keep it in there. Or I'd save my dollars to go solar or air-water before electric if NG didn't have a future.

Robert O'Brien

That's a dual aquastat, the low is just a reverse.

Robert O'Brien

If it weren't for LI, Honeywell wouldn't make that control

Robert O'Brien

Triple acting aquastats are the industry norm. There are a lot of 120v thermostats here and the preference for a high fixed temp equals a lot of dual aquastats.

Hilly

Triples are everywhere here. I'd say that is the only thing the oil companies will install around here.

Robert O'Brien

They set them 20 degrees apart, same as always!

Paul48

Boiler protection?

Paul48

@Hatterasguy

Can you give me a model number that reflects what you're talking about? I find double acting, that are all triple-aquastats. I believe you, I just need to see it to understand the difference.

Chamkila

Hatterasguy said:

Generally speaking, heating water using electric at $.15/KWH is going to be 2.5X more costly than heating with oil at $2.00/gallon.

So, you really have to ask yourself a question:

Why do I want to do that?

I am from queens and we have a natural gas hot water heater and I am used to long showers. 30 mins or more. And someone told me that with this coil you only get hot water for about 5 mins or so.

Chamkila

SWEI said:

Chamkila said:

I want to add this hot water heater from home depot.
...
I'm gonna run 8/3 wire with a 50 am 220 dual breaker.

I don't see a link or a photo of the heater in question, but a 50A circuit can deliver 9,600 Watts, which is quite a bit more than most residential tanks need. Side note: A 50A breaker requires either #8 THHN (in conduit) or #6 NM cable. You only need two hots (no neutral.)

You can pipe an electric tank heater as a buffer tank which will greatly boost your first hour capacity over the tankless coil alone. It can still use one of the electric elements as a booster or for backup.

Here is the hot water tank. I`m sorry i might have forgotten the link.

http://www.homedepot.com/p/Rheem-Performance-Platinum-50-Gal-Tall-12-Year-4500-4500-Watt-Elements-Electric-Water-Heater-with-LCD-Touch-Control-Display-XE50T12EC45U0/206282273


and how would i make this into a booster tank? I dont want to pay and arm and a leg every month. Would this go before the coil or after the coil? I am assuming this is what a booster is for right? Keep the electric hot water heater to the lowest setting so it is already warm by the time it gets to the coil right?

Chamkila

Robert O'Brien said:

Has to be Long Island with the dual aquastat! You may want to think twice with 23c Kwh

yes it is. Its in hicksville.

Robert O'Brien

Chamkila said:

Robert O'Brien said:

Has to be Long Island with the dual aquastat! You may want to think twice with 23c Kwh

yes it is. Its in hicksville.

Knew it!
I'd recommend an indirect and a triple aquastat.

Chamkila

Hatterasguy said:

Chamkila said:

and how would i make this into a booster tank? I dont want to pay and arm and a leg every month. Would this go before the coil or after the coil? I am assuming this is what a booster is for right? Keep the electric hot water heater to the lowest setting so it is already warm by the time it gets to the coil right?

You will pay an arm and a leg every month if the electric is utilized.

But, all you need is the storage capability of the tank. You already have the capability to heat the water with the tankless coil in the boiler. You setup a loop with a circulator (that is controlled by the tank aquastat) that goes from the tank to the tankless coil in the boiler and back. Once the tank drops below the setpoint (typically 140F), the circulator starts and the tank is heated via the tankless coil. The boiler also starts because its temperature is dropping due to the heat taken away by the tankless coil.

You get one of these:

http://www.homedepot.com/p/Rheem-Performance-Plus-50-Gal-Medium-9-Year-5500-5500-Watt-Elements-Electric-Water-Heater-with-LED-Indicator-XE50M09EL55U1/205810460

Instead of the internal thermostat running the lower coil, you wire it to run the circulator, instead. The circulator will run until that 'stat is satisfied.

If you decide to take a one hour shower, the upper thermostat can be set to operate the upper element and assist if the tank temperature drops below about 110F.

Man, this is getting really complicated. So the circulator will also be hooked up to run when the boiler is running as well right. Is there any pics you have or any diagrams that might help me setup my system. Thanks again so much for all your help.

Chamkila

Robert O'Brien said:

Chamkila said:

Robert O'Brien said:

Has to be Long Island with the dual aquastat! You may want to think twice with 23c Kwh

yes it is. Its in hicksville.

Knew it!
I'd recommend an indirect and a triple aquastat.

are you anywhere on the island? maybe you can help out thanks again.

SWEI

Where the heck is @icesailor when we need him? ISTR someone drawing up his recipe at one point, but it's pretty basic and if you already have a working tankless coil it's by far the best ROI you can get.

Hilly

use a brass/bronze/stainless circulator also

SWEI

http://forum.heatinghelp.com/discussion/142148/electric-tank-to-holding-tank describes the setup in a bit more detail.