# Ditch the HLT, go instant electric. Idea.

### Help Support Homebrew Talk:

#### Yorg

##### Well-Known Member
(Sorry about the long post, folks.)

I have an electric Urn as a HLT. It is too small, and rather than making a new electric HLT, I am considering the following. What do you think?

Instead of a HLT, make an electric instantaneous water supply.

See the attached diagram.

Electric because it is:
-Cheaper than LPG.
-Environmentally better if you buy green energy.

Some Benefits:
-Less energy wastage - only heat the water you use - no hot water sitting around on simmer.
-One less vessel
-Less space?
-About the same cost as a new electric HLT, if you look hard enough for parts?

How it works:
Essentially, a temp controller regulates an electric element.
A power switch activates a washing machine solenoid, and is a master switch for the element. No water flow, no power to the element.
It is off/solenoid closed when no water is required.
The Alarm function on the controller is set to go off if the water temp is too low. The Alarm output is used to drive washing machine solenoid valves. If the water is too cold while the element is heating up, the valves divert it away. If temp is ok, the valves allow the water to move to a flow meter and onwards to your mashtun. The flow meter has a digital readout.
The "Choke" valve at the front of the system is calibrated to provide a flow rate over the element that allows water to reach the highest temp desired, rather than rushing through at mains pressure.

Question:
Anyone know how to get an approximate calculation of the flow rate over a 240V 2400W element to give 75 degrees C (Sparge) - assuming an ambient water temp of 10C.
(This would tell me the max flow rate, and determine the practicality of the idea.)

Cheaper/Simpler Option:
1 Just work the flow rates that give Dough In and Sparge temps, use two choke valves - each set for one of those temps, and use a manual valve to divert the flow through the appropriate choke valve. (Would have to have consistant ambient water temps.)
2 Just use the choke valve and a thermometer. Manually hit the temp before using the water.

The detriment with these Options is you can't just dial in any temp and get the automated feed.

Cheers.

#### GuateBrewer

##### Well-Known Member
Electricity (watts): amps * volts
Heat (watts): Energy/Time (Joule per second)
4.18Joules = 1 Calorie
1 Calorie is the energy required to raise 1gram (or 1cc) of water by 1C.

Your unit would run at a snails pace.

Your wanting around a 150F raise in temp, even with a huge on demand heating unit pulling 88amps, you would only get an output of 1 gallon per minute.

That said if you ran it for 10 minutes of 1/6 of an hour at 21kw demand, you would use 3.5 kw/hrs of electricty time ?? 10-15cents per hour making it pretty cheap to heat the water 30-50cents?

Maybe plumb your domestic hot water supply though an on demand system?

##### Senior Member
Here are a couple formulas for water heating heat input in btu's
Flow in GPM X 500 X temperature rise =BTU's
BTU'S/3413 = KW needed

Here is an example 1GPMX500X120=60,000 BTU'S
60,000 BTU'S/3413=17.58 KW
(3 - 6000 watt elements)

Most residential service panels, feeders and meters would be unable to accept that much additional load and still operate major household appliances. Upgrade to service panel and feeders and meter would probably run \$1K+ as this is not a DIY project.

#### slnies

##### Well-Known Member
Good idea. But more practical as a lp system. Check out Kladue's on demand steam system. He uses a shrouded stainless coil heated by a burner. By flowing only ounces of water over a heated surface he can control heat with flow rate, just like what you are talking about. In fact, he also does his water heating for sparge and strike the same way to. Thought this might help you.

OP
Y

#### Yorg

##### Well-Known Member
Thanks very much folks.

#### modenacart

##### Well-Known Member
Just to let you know, the power company can charge you to upgrade the lines into your house if you use on demand hot water because it demands so much power at one time. You should look into your local utility's policies before installing any in demand hot water heater.

#### Bobby_M

##### Vendor and Brewer
Here are a couple formulas for water heating heat input in btu's
Flow in GPM X 500 X temperature rise =BTU's
BTU'S/3413 = KW needed

Here is an example 1GPMX500X120=60,000 BTU'S
60,000 BTU'S/3413=17.58 KW
(3 - 6000 watt elements)

Most residential service panels, feeders and meters would be unable to accept that much additional load and still operate major household appliances. Upgrade to service panel and feeders and meter would probably run \$1K+ as this is not a DIY project.

Good numbers. I wouldn't be too quick to dismiss this as impossible. Let's assume you have a 200 amp service and a 50amp/220 outlet in the garage for stick welding or even 50 amps of spare capacity.

I'd be happy waiting 24 minutes to get 6 gallons of strike water up to temp so that's .25 gpm.
If I start with 60F water and want to get it up to 170, that's a rise of 110F.
.25 x 500 x 110 = 13750 BTU / 3413 = 4KW. Hey, I can live with a 4500 watt element running 220. That's only 20amps.

Also, if you fly sparge, having an inflow of .25 gpm is fine. A 9 gallon sparge would take 36 minutes and you'd want to run that slower anyway.

#### CodeRage

##### Death by Magumba!
modenacart said:
Just to let you know, the power company can charge you to upgrade the lines into your house if you use on demand hot water because it demands so much power at one time. You should look into your local utility's policies before installing any in demand hot water heater.
Not only that, but they can charge you for the replacement of THEIR equipment and man hours to do it to support the additional load for that whole distribution area.

#### kickflip_mj

##### Well-Known Member
Ahh it might work, im taking an electrical and mechanical systems class and
i do know it takes 1 btu to turn 1cu/ft of water 1F. so let me do the math.
1 cf of water = 7.481 gal
1 gal= 8.33 lb
1 watt = 3.414btu's
So the equation shoud be
(Specific heat)(change in temp)(lbs)
so you take 1 btu(100F)(62.14lb)=6,214 btu's to raise the water from 70 degrees to 170 degrees.

1820 watt element for one hour to raise 7.481 gal of water

it can be done faster
3640 watt element in half an hour

7280 watt element for 10 minutes to raise 7.481 gal of water

basically put 3 2500 watt elements for ten minute

but honestly im not the expert i just know some math so do go off spending without double checking

##### Senior Member
Sorry but the formula for btu's is pounds of water times temperature change( BTU's=Lbs X temperature rise), the formula for gpm flow is pounds of water times temperature rise (BTU's per minute = GPM X 8.33 X Temperature rise). To get to btu's minute per KW of heat use 3413 btu's per hour / 60 minutes to get to temperature rise per pound of water per minute.

#### kickflip_mj

##### Well-Known Member
so your saying i did it all wrong?? its cool i hate doing those formulas anyways, they always kick my ass. do i get points for trying? lol

#### slnies

##### Well-Known Member
I will say one thing, the observations from this weekend brewing tells me Kladue is right on. I did get good results with my RIMS system heating the strike water to temp. But my system is heating two to three gallons for my mashes. I do five gallon batches. So my system heats in a quick fashion. If I were to go larger I would go steam because it is faster when designed right. If you don't mind the extra 20 minutes then electric is all right. As a note, most on demand water heaters are only good for a certain temperature rise. Here in Minnesota water can come out of the ground at 40F and even the big dogs will only get the water to a little over 100F. That is 60 degrees right now. That is also a 150 amp 240 volt heater. If I can find the manual I will post how many gallons a minute that is good for since I do not want to the math. So as a result here in Minnesota we do not install many on demand water heaters because the water is to cold in the winter. It should also be noted that if you live in a state that adopts the new 2008 electrical code the price of a service change out will go up on average of \$1500 in materials for a 100 amp service due to the new article changes involving arc-fault protection. Most states are not considering grandfathering in existing electrical, so even if your home is 1900 vintage. you will have to upgrade all circuits to accept arc-fault protection. If you are getting the picture, this means that on demand is getting way more expensive.

##### Well-Known Member
I am in process of building something similar but I took a slightly different approach.

I have a 12 gallon cooler with a PVC manifold in the bottom. From the cooler I am draining my mash unrestricted into a 1 gallon cooler that is below the level of the main cooler. The 1 gallon cooler has a 1500 watt heating element in it. Once the small cooler is full, it overflows into another hose that drains into the pump. The pump returns the wort to the sparge manifold at the top of my mash tun through a valve to control flow. I am going to use a Ranco with the probe in a thermowell at the output of the mash tun.

This is how it is going to work. Add 1.5 gallons to my strike water. Fill the cooler with hot tap water, set the Ranco to my desired strike temp and turn on the pump. Use valve to restrict flow of pump to a trickle. Once at strike temp. Turn off pump and ranco while I dough in. Once I have the grain in, slowly start recirculation through heated drink cooler and use Ranco to maintain mash temp.

Should have it all built next week.

Linc

##### Well-Known Member
Why reinvent the wheel?

Seems to me regular tank electric water heater would do the job in most cases. Possibly with some supplimential heat supplied from a LP burner for the last little bit of heat if needed. Or a little bit of tinkering with the thermostat if needed.

##### Well-Known Member
I'm not sure but I have heard that a hot water heater will not exceed 150 F

##### Well-Known Member
Some of the older one's will also some industrial types but that's why I said use LP burner to supplement the last little bit of heat or tinker with the thermostat.

To the OP you're right electricty is cheaper, but greener no way unless it's hydro, wind, solar or geothermally generated. You'd be hard pressed to argue that nuclear, coal-fired or natural gas is greener than LP. The carbon emissions or nuclear waste are just generated off site.

#### slnies

##### Well-Known Member
I'm not sure but I have heard that a hot water heater will not exceed 150 F
Just thier T-stats

#### Bobby_M

##### Vendor and Brewer
The instant heater idea is ideal because it doesn't not rely on moving a large column of water with mechanical means to keep it heating. In a water heater tank, they just let time and convection work but we're talking about shortening the brewday as much as possible.

The idea is to flow a small amount of water past a large element so that it's up to temp as it exits. I really don't mind .25 gpm as I said. Who would? It's fast enough for sparging and certainly on par with any gas fired kettle.

Where the wattage numbers correct for .25 gpm at 110F temp rise?

#### modenacart

##### Well-Known Member
Some of the older one's will also some industrial types but that's why I said use LP burner to supplement the last little bit of heat or tinker with the thermostat.

To the OP you're right electricty is cheaper, but greener no way unless it's hydro, wind, solar or geothermally generated. You'd be hard pressed to argue that nuclear, coal-fired or natural gas is greener than LP. The carbon emissions or nuclear waste are just generated off site.
Hydro is one of the most destructive power sources on the enviroment. It destroys all the local ecosystems. I am surprised that its considered green energy.

#### slnies

##### Well-Known Member
Bobby,
You could wire up an element in the HLT, hook it up to a love control and then put it on a timer. This way, in the morning before you go to work, you fill up the HLT, and an hour or two before you come home the element fires up and when you walk in the door you add your crush to the MLT and doe in. While the mash is under way you can dial up the control to your sparge temp, and when the mash is done, you are ready to go to sparge. How do you like them apples?

##### Senior Member
Bobby, .25GPM with 110 degree rise is 4.03KW, a 4500 watt element should do the job. The trick will be to get enough flow over the entire element to prevent localized overheating and boiling. Looks like the lowest watt density element would be the safest bet at that low a flow level with no outlet valving to prevent a loud and painful suprise if element is fired with no way to relieve pressure.

#### Bobby_M

##### Vendor and Brewer
slnies said:
Bobby,
You could wire up an element in the HLT, hook it up to a love control and then put it on a timer. This way, in the morning before you go to work, you fill up the HLT, and an hour or two before you come home the element fires up and when you walk in the door you add your crush to the MLT and doe in. While the mash is under way you can dial up the control to your sparge temp, and when the mash is done, you are ready to go to sparge. How do you like them apples?
I'm not like a paranoid grandmother that unplugs all appliances before I can sleep at night, but I don't think I'd want some DIY automated system energizing a 4500 watt device sitting in water while I wasn't around.

I'm just really digging the idea inline heating right now (as I drudge along on my natural gas brewstand of course).

#### Jaybird

hell I start my (Electric) system @ 5 AM and sleep like a baby till 6 AM and doe in and sleep like a baby till 7 AM I love my (Electric) system... I can be done @ noon and still get a round of 18 in LOL ( I quit golfing when I started brewing)

OP
Y

#### Yorg

##### Well-Known Member
A few things:

1a
Am I reading correctly: Even at the highest temp ramp - up to sparge temp - a 4500W @ 240V element will enable about a .25 gall or about a quart/liter flow rate per minute?
1b
As per my original question - sorry I am math challenged:
What is the flow rate generated for a ramp of 120 degrees F to 170 degrees, from a 50 degree starting point?
2
Re Kladue's point about localised boiling/overheating. If enough downstream tubing length and a little turbulence is incorporated into the design, by the time the water reaches the outlet, it is mixed around to equilibrium. A regular density element of modest length should be ok. (Assuming the design in the first post - of wiring the element power with the solenoid so that water must be flowing for the element to be powered) I can't see a huge issue - am i missing something?
3
Where I live, I can buy energy that is accredited as 'green' by the government. Totally sustainable. It costs about a third more. So for me this is genuinely better for the environment than gas (though still not a conclusive argument over a regular electric HLT).

#### slnies

##### Well-Known Member
Bobby_M said:
I'm not like a paranoid grandmother that unplugs all appliances before I can sleep at night, but I don't think I'd want some DIY automated system energizing a 4500 watt device sitting in water while I wasn't around.

I'm just really digging the idea inline heating right now (as I drudge along on my natural gas brewstand of course).
Be nice now! What you proposed is a DIY project as well. I only brought it up because it might help. Although I do like Kladue's Idea with the 4500 watt element and a .25 GPM flow rate. I like having things ready when I walk through the door, so the HLT idea was good. Besides, what is t he worst that could happen if something went wrong while you were gone? The element miss fires with no water in the tank, and it melts down, shorts out, and trips the breaker. I can only see a problem with a plastic HLT in that respect. I have already destroyed two elements testing for fire hazards with my RIMS system, and that is what happens. The element just melts down. Twenty dollars latter and your ready to go.

##### Well-Known Member
modenacart said:
Hydro is one of the most destructive power sources on the enviroment. It destroys all the local ecosystems. I am surprised that its considered green energy.
Well I'd agree that hydro is not without costs but it is also not without some benefit as well. The impoundments provide sports and recreation activity, helps with flood control and provides a resevoir of fresh water for farming and household water needs. It also helps maintain navigable waterways.

As far as a regular tank type water heater is concerned. I have a timer on the water heater cuts off the electricty at night and during the day or at peak rate periods depending on how I program it. I'd venture to say that the \$35 timer saves me about as much money as an on demand water heater that may cost
100 x that much to buy and install.
.

No reason a timer like that couldn't be used for a brewing setup. If you want to start brewing at 6am set the timer for 5am and your ready when you walk in the door.

#### Bobby_M

##### Vendor and Brewer
slnies said:
Be nice now! What you proposed is a DIY project as well. I only brought it up because it might help. Although I do like Kladue's Idea with the 4500 watt element and a .25 GPM flow rate. I like having things ready when I walk through the door, so the HLT idea was good. Besides, what is t he worst that could happen if something went wrong while you were gone? The element miss fires with no water in the tank, and it melts down, shorts out, and trips the breaker. I can only see a problem with a plastic HLT in that respect. I have already destroyed two elements testing for fire hazards with my RIMS system, and that is what happens. The element just melts down. Twenty dollars latter and your ready to go.
Hey, I forgot the smilies to denote my joking tone!

I guess another way I'd think of it is with the on-demand system, you walk into the brew area, open the valve and enable the heating system. You then weigh out your malt and crush it and by the time you get that done, you have your 6 gallons of strike water in the MLT (figuring a 10 gallon batch).

Assuming you use PID, you can then use the same heating mechanism for HERMS. You might even switch over to 120v for that purpose to avoid scorching.

Then when you're ready to sparge, you crank up the on-demand heating and run .2 gpm or so. The best part of this system would be sparge water already under pressure from the tap so you don't need a pump or height.

I'd would mount the element vertically in the thinnest copper tube it would fit in, probably 1.5" or maybe 2". The water/wort inflow would be at the bottom, outflow at the top, overpressure relief valve at the very top. I'd never run it with the outflow closed off but the overpressure valve would be the safety. I would also assume that you'd have your temp controller cutting power well before it got to boiling temps.

Just thinking here....

##### Senior Member
Design your chamber with element in vertical with terminal end at bottom, design piping so the chamber retains water by bringing inlet pipe up to outlet elevation. This should help prevent a dry fire situation, and if you put the valve on the inlet and connect outlet to sparge ring with no valve in outlet line the worst you would get is steam in the mashtun.

#### slnies

##### Well-Known Member
I'd would mount the element vertically in the thinnest copper tube it would fit in, probably 1.5" or maybe 2". The water/wort inflow would be at the bottom, outflow at the top, overpressure relief valve at the very top. I'd never run it with the outflow closed off but the overpressure valve would be the safety. I would also assume that you'd have your temp controller cutting power well before it got to boiling temps.

Just thinking here....
For your copper, use the 1.5 inch if your looking for the smallest. With this size you will have to bend the element slightly to make free and clear clearance. But it works great, and the smaller manifold is easier to clean when you are done, not to mention a little cheaper to buy if you have to buy it from a hardware store. S.

#### Bobby_M

##### Vendor and Brewer
This is just one more reason I'm thrilled to be near a scrap yard that actually leaves their stuff sitting around in bins for a while prior to crushing. I've found a ton of copper fittings and short pieces of large diameter pipe. They says, "uh, you know we're getting like 2 bucks a pound right?" Yes sir, here's your 12 bucks for \$80 (retail) worth of fittings.

#### CodeRage

##### Death by Magumba!
Hey Slnies, look familar? I can post the parts for mail order if you like.

#### slnies

##### Well-Known Member
Virtuous said:
Hey Slnies, look familar? I can post the parts for mail order if you like.
Good job. Looks exactly like mine. You just need to sweat it together. Let my know how it works for you when you get it up and running.

#### Bobby_M

##### Vendor and Brewer
Any thoughts about insulating this thing?

#### slnies

##### Well-Known Member
Bobby_M said:
Any thoughts about insulating this thing?
Ya, go ahead. One reservation though, make sure the insulation will handle the heats you are looking to run. I would not hesitate to insulate mine, but I never reach anywhere above 180F. I am in the process now of building the HLT. It is also electric. The HLT is however being set up on a timer in combination with a low level sensor. This way if the water is too low it just shuts the element down; and yes, it will be temperature controlled. The next automation idea will be to set up a solenoid to the incoming water, and when the timer goes off the solenoid opens up and fills the HLT. When the water reaches the HLT high water limit the solenoid shuts down. The only thing I think I will really have to engineer is some more plumbing in case the solenoid fails. I don't want a flood.

#### CodeRage

##### Death by Magumba!
Just plumb two solenoids in series.

#### slnies

##### Well-Known Member
Virtuous said:
Just plumb two solenoids in series.
Good Idea! Then, when it hits the high limit, it is done for good. I like it.

#### Jim Karr

##### Well-Known Member
So the solenoids would be like water inlet valves used on a washing machine?

#### slnies

##### Well-Known Member
Jim Karr said:
So the solenoids would be like water inlet valves used on a washing machine?
Yup! You have the idea.