Best way to do DHW

Re: Best way to do DHW

PostBy: Pacowy On: Tue Nov 05, 2013 1:48 pm

Sting wrote:option one as it is provides NO SCALD PROTECTION

Very dangerous


Point taken, but IMO overdramaticized. To clarify, a tempering valve should be used so that the user is not cooked. Does that help?

Mike
Pacowy
 
Stoker Coal Boiler: H.B. Smith 350 Mills boiler/EFM 85R stoker
Coal Size/Type: Buckwheat/anthracite

Re: Best way to do DHW

PostBy: NJJoe On: Tue Nov 05, 2013 1:53 pm

Thanks so far guys, please keep them coming. What about option 4? No love for the ergomax?
NJJoe
 

Re: Best way to do DHW

PostBy: Sting On: Tue Nov 05, 2013 1:55 pm

it Depends Mike :D

when the appliance is on a low sustained idle - it is simply holding temp
there may not be enough energy in the box for option one to heat the leg to 120

and yes - the protection valve does the trick -- when it functions correctly and doesn't stick
Sting
 
Other Heating: OBSO Lennox Pulse "Air Scorcher" burning NG

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Re: Best way to do DHW

PostBy: Sting On: Tue Nov 05, 2013 1:59 pm

NJJoe wrote:Thanks so far guys, please keep them coming. What about option 4? No love for the ergomax?


redundant -- since you already have the coil in the applinace

NOW= if the appliance coil is too small to meet the demand - or if its plugged - or some how its function is impaired = well that's another color
Sting
 
Other Heating: OBSO Lennox Pulse "Air Scorcher" burning NG

Re: Best way to do DHW

PostBy: Pacowy On: Tue Nov 05, 2013 2:08 pm

Townsend wrote:Mike, you have been around long enough to know the virtues of the AA/AHS without resorting to the "probably" clause!!! :D Or at least certainly know the attitudes of the Axeman men and how they feel about their boilers. Come on, you can do it, admit they're just as good as the EFMs, only different!!!


I am quite familiar with the attitudes. :lol: I don't want to try to speak for the AA/AHS guys and I don't think I need to. Anything I think I might know about AA/AHS equipment is only from what I've seen on this forum. If anything, for someone with zero AA/AHS experience, I thought my original wording was pretty neutral regarding EFM's vs. AA/AHS's. "That's my story and I'm sticking to it." :D

Mike
Pacowy
 
Stoker Coal Boiler: H.B. Smith 350 Mills boiler/EFM 85R stoker
Coal Size/Type: Buckwheat/anthracite

Re: Best way to do DHW

PostBy: fifthg On: Tue Nov 05, 2013 2:11 pm

mixing valve is good,but scalding shouldn't be an issue if you don't set the upper limit too high.There is no need to do so.The hotter you go,the harder on the system,so there is another reason not to.
fifthg
 
Stoker Coal Boiler: EFM 520
Hot Air Coal Stoker Furnace: Harman DVC 500
Hand Fed Coal Stove: warm morning
Baseburners & Antiques: Reading Foundry & Supply Co.
Coal Size/Type: rice,pea ,nut,stove Gale Mining Co Anthracite

Re: Best way to do DHW

PostBy: Pacowy On: Tue Nov 05, 2013 2:15 pm

Sting wrote:it Depends Mike :D

when the appliance is on a low sustained idle - it is simply holding temp
there may not be enough energy in the box for option one to heat the leg to 120

and yes - the protection valve does the trick -- when it functions correctly and doesn't stick


Nice rhyme. :D

Not sure I get your point on the low sustained idle. The low limit on the aquastat should be set to kick the stoker on before a DHW draw has a chance to drag the boiler temp too low. Does that address the "not enough energy" issue?

Mike
Pacowy
 
Stoker Coal Boiler: H.B. Smith 350 Mills boiler/EFM 85R stoker
Coal Size/Type: Buckwheat/anthracite

Re: Best way to do DHW

PostBy: Sting On: Tue Nov 05, 2013 2:22 pm

I was thinking this was a furnace -- not a boiler

confused in Cheese Head land - but my collar bone isn't broken
Sting
 
Other Heating: OBSO Lennox Pulse "Air Scorcher" burning NG

Re: Best way to do DHW

PostBy: Pacowy On: Tue Nov 05, 2013 2:23 pm

fifthg wrote:mixing valve is good,but scalding shouldn't be an issue if you don't set the upper limit too high.There is no need to do so.The hotter you go,the harder on the system,so there is another reason not to.


My coil was in a steam boiler with a single aquastat that controlled only the low limit. IIRC it was set at 160 deg in the summer. The boiler water needs to be enough above 120 degrees that the cold incoming water can reach 120 degrees during the limited time it's running through the coil. That said, the first blast of coil water coming out at 160 can use some tempering, and the first blast that comes out while you're making steam can use a lot of tempering.

Mike
Last edited by Pacowy on Tue Nov 05, 2013 3:50 pm, edited 1 time in total.
Pacowy
 
Stoker Coal Boiler: H.B. Smith 350 Mills boiler/EFM 85R stoker
Coal Size/Type: Buckwheat/anthracite

Re: Best way to do DHW

PostBy: Carbon12 On: Tue Nov 05, 2013 3:36 pm

I decided to try using the electric hot water heater as a sorage tank plumbed with the boilers DHW coil into the cold side of hot water heater with appropriate valves. Used a tempering valve at boiler to reduce 180 degree boiler water temp to 140. Uses less of the boiler heat. Water heater set at about 100. So far the water in the water heater has not dipped below 120 with normal use. Thought that might save the energy stored in the boiler for high heating loads with low outdoor temps. Will evaluate how this works out and plumb differently if necessary. Will try using boiler for DHW over summer as well. Have not ruled out a Zoned indirect water heater.
Carbon12
 
Stoker Coal Boiler: Keystoker KA-6
Coal Size/Type: Rice/Anthracite
Other Heating: Heat Pump/Forced Hot Air Oil Furnace

Re: Best way to do DHW

PostBy: tsb On: Tue Nov 05, 2013 6:13 pm

On my home brewed system, I left the hot water heater plumbed as usual.
Cold in Hot out. I then plumbed a loop to the DHW coil in the boiler with
a potable water pump and a temperature probe switch. Hot from the boiler
into the bottom drain and the return cut into the cold in line at the top.
The tank is maintained at 120. The gas burner is set at 100. Never had
a problem with not having enough hot water. I even use it to hose ice
off the steps in the winter time.
tsb
 
Stoker Coal Boiler: Binford 2000
Hot Air Coal Stoker Stove: LL Pioneer top vent
Hand Fed Coal Stove: Saey Hanover II

Re: Best way to do DHW

PostBy: GoodProphets On: Tue Nov 05, 2013 8:18 pm

i have a EFM 520 with DHW coil

The electric water heater is still plumbed in with shut off valves and is bypassed.

I also have valves on the in/out for the DHW coil to bypass.

I chose to run the 520 last summer (first summer) and all went well.
I do not have a need to use the elec WH, but it is there for backup.

You do need to bypass the boiler if you shut it down, but either way you need to keep the
boiler free from moisture, so best bet is to keep it running.
I plan to with 3 kids (soon 4) and lost of laundry and stuff.

We cannot run two showers at a time (although I have not fully confirmed this, only take it from what i heard)
But possibly could with adjustment to tempering valve or boiler temp.

And having it for a full calender year, no problems.
Did take some adjusting a bit n such until becoming experienced.
Once it was fine tuned for my draft and such, no out fires or hi temps...idles perfect.

Just had the coal bin built, so no more bags....HERE WE GO!

Nice heat and hot water for cheeeep, with no worries of kids taking LONG showers
GoodProphets
 
Stoker Coal Boiler: EFM DF520
Coal Size/Type: Anthra Rice
Other Heating: 3 Fireplaces

Re: Best way to do DHW

PostBy: SMITTY On: Tue Nov 05, 2013 11:47 pm

Indirect HW tank was the BEST thing we ever did. Amtrol Boilermate. Aside from a damn electronics failure at year 8 ( Fixing the dreaded Boilermate buzz: control board repair ), this thing has been awesome. Holds heat forever. While doing my boiler install, I had an ice cold boiler completely empty, and was still able to take a shower with 120° water. Gotta love it.

On top of that, no matter how many back-to-back showers we take, we never run out of HW. I usually fire up the laundry, then the dishwasher, let my wife start the shower and I join her soon after (TMI, sorry .. :lol: ). Water never ever gets lukewarm. It's always HOT! 8-)

I'm hoping Sting will chime in again. That avatar is absolutely WONDERFUL ... :love: :drool: toothy
SMITTY
 
Stoker Coal Boiler: Patriot Coal - custom built by Jim Dorsey
Hand Fed Coal Stove: Harman Mark III (not currently in use)
Coal Size/Type: Rice / Blaschak anthracite
Other Heating: Oil fired Burnham boiler

Re: Best way to do DHW

PostBy: oliver power On: Wed Nov 06, 2013 9:48 pm

I think you should have an option #5 (electric hot water heater). Shut boiler down in summer months, and use electric hot water heater. I'm all plumbed into my primary loop for an indirect hot water tank. The only thing I need is the tank itself. My electric hot water tank doesn't cost much at all to operate. I'm not in any hurry to spend $1,000.00 on a indirect tank.
oliver power
 
Stoker Coal Boiler: KEYSTOKER Kaa-2
Hand Fed Coal Stove: Hitzer 50-93 & 30-95, Vigilant (pre-Vigilant-II)
Baseburners & Antiques: MANY (Mostly when burning wood)
Stove/Furnace Make: HITZER / KEYSTOKER
Stove/Furnace Model: 50-93 & 30-95 , Kaa-2

Re: Best way to do DHW

PostBy: oilman On: Wed Nov 06, 2013 9:50 pm

The Ergomax is just a tankless coil in a tank- in other words, you will get the same thing with your boiler. I would go with the coil with a booster tank.
The main thing is, you will double the life of your boiler if you run it all year. Heat only boilers have a very tough life. Sitting there cold all summer just eats them up.
oilman
 

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