Problems With KAA-2 Temps.

 
User avatar
Sting
Member
Posts: 2983
Joined: Mon. Feb. 25, 2008 4:24 pm
Location: Lower Fox Valley = Wisconsin
Other Heating: OBSO Lennox Pulse "Air Scorcher" burning NG

Post by Sting » Fri. Jan. 24, 2014 2:17 pm

kstills wrote:
Sting wrote:Sounds like a typical over pumping drama -- :D

Do a little searching regarding system balance!
Yeah, but eventually (unless his heat loss exceeded his btuh) he would catch up, right?
it Depends -- probably not until the weather moderates

- so yes - eventually but not due to system performance= due to load decrease


 
User avatar
Carbon12
Member
Posts: 2226
Joined: Tue. Oct. 11, 2011 6:53 pm
Location: Harrisburg, PA
Stoker Coal Boiler: Keystoker KA-6
Coal Size/Type: Rice/Anthracite
Other Heating: Heat Pump/Forced Hot Air Oil Furnace

Post by Carbon12 » Fri. Jan. 24, 2014 2:20 pm

This weather has been A LOT colder for A LOT longer this winter than the previous 2 winters where his system appeared to work well.

 
kstills
Member
Posts: 637
Joined: Tue. Jan. 18, 2011 6:41 am
Location: New Britain, PA
Stoker Coal Boiler: WL 110

Post by kstills » Fri. Jan. 24, 2014 2:32 pm

Sting wrote:
it Depends -- probably not until the weather moderates

- so yes - eventually but not due to system performance= due to load decrease
Cryptic and oddly unsatisfying as an answer (because I keep clicking on those underlined passages, only to find out they aren't hyperlinks).

In my situation, it takes a while for the system to 'balance', IE come up to temp where the water is actually circulating without the low limit being breached. In warmer weather, this never happens. In this extreme cold, the boiler might run 1/2 the night.

Eventually, I'm circulating water above the 160ll. Then the demand is satsified, and the boiler shuts off. And I'm pushing ~75g of water around both zones.

IF my heat loss exceeded my boiler's ability to match it, my boiler would never shut off, however the water temp in the system should eventually hit the ll and stay there (unless the heat loss was massively higher than the btuh of the boiler).

Balancing the system, if I understand it correctly, makes the boiler run full out from the get go, or close enough to make the difference negligible. It does this by restricting flow, reducing the return temp of the water, keeping hotter water in the living areas and forcing the boiler to run more or less continuously.

I'm just not seeing how this helps anymore than the other method if the hl exceeds the btuh output.

 
User avatar
Sting
Member
Posts: 2983
Joined: Mon. Feb. 25, 2008 4:24 pm
Location: Lower Fox Valley = Wisconsin
Other Heating: OBSO Lennox Pulse "Air Scorcher" burning NG

Post by Sting » Fri. Jan. 24, 2014 3:17 pm

kstills wrote:I'm just not seeing how this helps
You can lead a horse to water - but you cannot make him drink

or

"I don't know the key to success, but the key to failure is trying to please everybody." –Bill Cosby

 
kstills
Member
Posts: 637
Joined: Tue. Jan. 18, 2011 6:41 am
Location: New Britain, PA
Stoker Coal Boiler: WL 110

Post by kstills » Fri. Jan. 24, 2014 3:27 pm

Sting wrote:
kstills wrote:I'm just not seeing how this helps
You can lead a horse to water - but you cannot make him drink

or

"I don't know the key to success, but the key to failure is trying to please everybody." –Bill Cosby
Ooops, talked at length about something besides system balance.
:oops:

However I don't see how a 900 sq foot dwelling can have a system balance issue great enough to overcome the boiler's capacity to make enough hot water to eventually heat the house.

 
waldo lemieux
Member
Posts: 2270
Joined: Sun. Sep. 30, 2012 8:20 pm
Location: Ithaca,NY

Post by waldo lemieux » Fri. Jan. 24, 2014 3:40 pm

How about a bypass loop w/ throtle valve to temper the cold water returning to the boiler. You don't by chance have 4or 5 big iron radiators on one zone do you? just thinkin on line :D

 
User avatar
Sting
Member
Posts: 2983
Joined: Mon. Feb. 25, 2008 4:24 pm
Location: Lower Fox Valley = Wisconsin
Other Heating: OBSO Lennox Pulse "Air Scorcher" burning NG

Post by Sting » Fri. Jan. 24, 2014 3:42 pm

kstills wrote: Balancing the system, if I understand it correctly, makes the boiler run full out from the get go, or close enough to make the difference negligible. It does this by restricting flow, reducing the return temp of the water, keeping hotter water in the living areas and forcing the boiler to run more or less continuously.
Where on earth did you draw this conclusion from
Image


 
User avatar
tsb
Member
Posts: 2621
Joined: Wed. Jul. 30, 2008 8:38 pm
Location: Douglassville, Pa
Stoker Coal Boiler: Binford 2000
Hot Air Coal Stoker Stove: LL Pioneer top vent
Hand Fed Coal Stove: Saey Hanover II
Baseburners & Antiques: Grander Golden Oak , Glenwood # 6
Coal Size/Type: All of them

Post by tsb » Fri. Jan. 24, 2014 3:42 pm

My home built boiler is no bigger than a Kaa-2 and it runs
balls to the walls in this weather. The T-stats run the circulator
and the aquastat runs the stoker. The stoker runs flat out almost all
the time and the water never gets below 150-160. The house is
about 4000 sq feet. 2000 gets heated to 72-73 and the rest is what
ever it is. The basement is ground floor and also 2000 sq feet, but is
still 50 degrees. Maybe just shitty coal.

 
farrell2k
Member
Posts: 217
Joined: Sun. Nov. 11, 2012 4:38 pm
Location: Perkasie Pa.
Stoker Coal Boiler: Kaa2

Post by farrell2k » Fri. Jan. 24, 2014 3:45 pm

waldo lemieux wrote:How about a bypass loop w/ throtle valve to temper the cold water returning to the boiler. You don't by chance have 4or 5 big iron radiators on one zone do you? just thinkin on line :D
It's hot water baseboard. I think 100 ft of it. It's such a small house, which is what is so weird about this.

So my boiler has no problem getting up to temperature. I have it set to 170/190/15 diff and the bioler temp is now close to 180, but I just can't get the house warmer than 68* :(

 
kstills
Member
Posts: 637
Joined: Tue. Jan. 18, 2011 6:41 am
Location: New Britain, PA
Stoker Coal Boiler: WL 110

Post by kstills » Fri. Jan. 24, 2014 3:57 pm

farrell2k wrote:
waldo lemieux wrote:How about a bypass loop w/ throtle valve to temper the cold water returning to the boiler. You don't by chance have 4or 5 big iron radiators on one zone do you? just thinkin on line :D
It's hot water baseboard. I think 100 ft of it. It's such a small house, which is what is so weird about this.

So my boiler has no problem getting up to temperature. I have it set to 170/190/15 diff and the bioler temp is now close to 180, but I just can't get the house warmer than 68* :(
Ding!

This may be the problem....

Now, does the boiler ever shut off?

At 180f, 100ft gives ~61k btuh at 4gpm...

No insulation, any idea what your heat loss is at these temps?

 
User avatar
Sting
Member
Posts: 2983
Joined: Mon. Feb. 25, 2008 4:24 pm
Location: Lower Fox Valley = Wisconsin
Other Heating: OBSO Lennox Pulse "Air Scorcher" burning NG

Post by Sting » Fri. Jan. 24, 2014 4:05 pm

farrell2k wrote:
waldo lemieux wrote:How about a bypass loop w/ throtle valve to temper the cold water returning to the boiler. You don't by chance have 4or 5 big iron radiators on one zone do you? just thinkin on line :D
It's hot water baseboard. I think 100 ft of it. It's such a small house, which is what is so weird about this.

So my boiler has no problem getting up to temperature. I have it set to 170/190/15 diff and the bioler temp is now close to 180, but I just can't get the house warmer than 68* :(
What temperature is the return pipe near the boiler?

What temperature is the supply pipe ?? Hey Folks maybe this appliance already does have a bypass -- can we see any pictures?

 
User avatar
Carbon12
Member
Posts: 2226
Joined: Tue. Oct. 11, 2011 6:53 pm
Location: Harrisburg, PA
Stoker Coal Boiler: Keystoker KA-6
Coal Size/Type: Rice/Anthracite
Other Heating: Heat Pump/Forced Hot Air Oil Furnace

Post by Carbon12 » Fri. Jan. 24, 2014 4:08 pm

I'm just glad my suggestion has seemingly improved the situation a bit. Let's bring all home boy! Take the temps and post the photos! :D

 
kstills
Member
Posts: 637
Joined: Tue. Jan. 18, 2011 6:41 am
Location: New Britain, PA
Stoker Coal Boiler: WL 110

Post by kstills » Fri. Jan. 24, 2014 4:11 pm

Kaa2 output is ~76k net, which is right about near his current radiation.

 
KLook
Member
Posts: 5791
Joined: Sun. Feb. 17, 2008 1:08 pm
Location: Harrison, Tenn
Other Heating: Wishing it was cold enough for coal here....not really

Post by KLook » Fri. Jan. 24, 2014 4:38 pm

I suspect poor flow. Either air bound or circulator problem. Maybe a valve got turned accidentally. That is why the output and return temps would be nice to know.

Kevin

 
farrell2k
Member
Posts: 217
Joined: Sun. Nov. 11, 2012 4:38 pm
Location: Perkasie Pa.
Stoker Coal Boiler: Kaa2

Post by farrell2k » Fri. Jan. 24, 2014 5:10 pm

I have no way to measure any temps right now, but the water leaving the circulator is damned hot to the point where I can only touch the pipe for a few seconds.

There is a bypass loop, at least that's what I was told. Please ignore the mess. I didn't have the motivation to clean anything but the essentials on the boiler this season.

I used to have two zones set up on the old oil boiler, but now I only have one that controls both circulators. I was experimenting before and disconnected the circulator that pumps upatairs. I was able to get the downstairs to 70 when I did this. I am now thinking that too much water is leaving the boiler to satisfy the thermostat. Does that make any sense?
20140124_164727.jpg
.JPG | 126.5KB | 20140124_164727.jpg
20140124_164814.jpg
.JPG | 100.7KB | 20140124_164814.jpg
20140124_164800.jpg
.JPG | 133.2KB | 20140124_164800.jpg


Post Reply

Return to “Stoker Coal Boilers Using Anthracite (Hydronic & Steam)”