How Can I Get More Heat Out of My Keystoker - KA6 Boiler?

Finally got some cold weather this AM, -2 degrees this morning. Thermostat set at night to 64 degrees. Got up at 5:30 AM and pushed it to 70 degrees. Took 5+ hours to go up 6 degrees. Do I need to open the large air-shutter to full open in these conditions? Otherwise the boiler seems to be running & burning properly. House is 2300 sq. feet, single loop zone, 50% log home built in the mid 70's and 50% framed home built in the mid 80's with full basements under all. Insulation in framed walls is R-11 and in the ceilings of both only R-19 unfortunately. Windows & doors are tight and log walls are tight also. Log wall thickness is 6" to 7" thick. Any ideas?

Thanks!

Coal burns hot, BUT , coal burns slow. If you want your house at 70*, leave it at that temp 24/7,forget the setback to save oil or gas,this is coal !! You will be warmer,your house will be warmer & everything & everyone will feel warmer,everyone will be

You can use setbacks and save fuel but need to start the recovery ahead of time (e.g., with a programmable thermostat). That said, 5+ hours is a long time if the unit is working right.

A few thoughts:

- I'm pretty sure the procedure for setting the air is in the manual.
- During the long run how wide was the band of ash at the end of the stoker? If it was not very close to 2", your fuel/air mix is off and you aren't getting full output.
- Is the coal real wet and/or does it have a lot of fines and undersized pieces? Coal should be at most damp, clean and uniformly sized.
- IMO buck is better than rice to get max output under heavy load.
- Is there a barometric damper in place and is it functioning properly?
- Have sources of air infiltration to combustion chamber been controlled (e.g., ash door gasketed and secured, fire door latched, etc.)?

Mike

I have a few questions that will help sort this out.

1. Did your radiation heat the house properly before you installed the KA-6?
2. What is the high limit setting on the KA-6?
3. Did the boiler reaching the high limit setting during the 5 hour heat call?

If the boiler is reaching the high limit setting and the circulator is running nonstop, it is not a boiler capacity issue.

x2 on Rob's questions.

Also, is there unobstructed airflow around your radiation (e.g., carpets or sofas blocking baseboards)?

Mike

As Windy Hill has mentioned you have to forget the
use of the set back thermostat as the KAA-6 cannot
respond instantly to the heating load.

As he said set the thermostat where you want it and
just let the K6 work with the air shutter and stroke
settings you have.

Just be sure that:

1. the stoker fire bed is clean and the air holes
in the firebed sections are open.
a. The flue pipes are clean.
b. the flue pipes are sealed properly
c. the carbon monoxide/smoke detector is working properly
d. the combustion fans are clean and free of dirt if your unit has the new two fan system.
e. the chimney junction for the flue pipe is clean
f. you have the recommended "Draft" "Hg water gauge" readings "
pressure gradient generated for the KAA-6.

All you can do is wait for the boiler to catch up until it reaches the 70 degree temp once you
set it at 70 degrees as the boiler is simply reacting to you set back thermostats commands
and the lower overnight temps are a direct result of the thermostats commanding the boiler
to slow down.

What you have is a dramatic soap opera, and you are viewing the true laws of thermodynamics at work and your "heating load" is the laboratory.

Wherein:

The hypothesis is how much heat in "Btuh" British Thermal Units per hour do I need to heat my home?

The experiment:
How do I run the KAA-6 boiler to have a 70 degree temperature at all times when I use a set back thermostat?

The conclusion:

a. the KAA-6 is slowing down when the thermostat is telling it to slow down and go to the low temperature setting.

b. the hot water in the boiler has been satisfied and stays at this low temperature and maintaining the lower temperature during the time of temperature set back during the night hours.

b1. the home is continuing to have heat loss during the set back times programmed into the thermostat.

c. when the thermostat calls for heat the boiler begins the work of burning coal and the process begins again and the boiler is again doing its job of making hot water for the heating load and will continue to make hot water until
the thermostat is satisfied.

The KAA-6 cannot and will not react instantly and that is the conclusion of your thermodynamics experiment in home heating.

Your seeing the All the Laws Of Physics and thermodynamics at work "up close and personally".
=======================================================================================
There is "magic in the burning of the black rocks" but it takes a while to tap into it and make it work
and work well.

Holy smokes! That is a lot of info! I guess I am used to burning my H.B. Smith 7 section cast iron wood/coal boiler with wood for 40 years & that had not problem doing the job. Of course there was no thermostat, just an aquastat, so it ran continuously until you stopped feeding it or opened the windows! Burning coal is different and I will have to get used to it. Brand new boiler this early fall with just over 2 tons burned so far. Thanks for all the info guys, I do appreciate it!

The "laws of physics and thermodynamics", as well as experimental evidence, make it abundantly clear that your heat loss is reduced by setting the temperature back at night (or whenever a living space doesn't need to be heated for an extended period). You can reduce your heating costs this way. With coal or any other fuel you won't be able to instantly restore your desired "daytime" temps, so setback thermostats can be useful.

The Keystoker may be a little slower than other coal boilers to ramp up to full output if it is equipped with the secondary blower. Among the other "benefits" of that pesky device are the elimination of burnable coal over the air holes on the grate and the cooling of boiler water toward the low limit. The stoker has to work for a while to overcome those factors.

Mike

How low did the boiler temp drop?

If you have a house that is so well insulated & air tight that you can heat it with a candle in each room,....... your house qualifies for the set back program. Otherwise keep everything inside your house heated to your comfort zone level............all the time. OR.... if you don't mind being uncomfortable during the set back & recovery times , go for the set back.

Log houses have a lot of thermal mass and don't respond as quickly as some other homes...but 5 hours seems excessive any way you slice it.

Please answer the questions below. Everyone is focusing on the boiler and debating temperature setbacks, when it might be as simple as the Hydrostat control on the Keystoker is set improperly...they have an economy setting that can prevent the boiler temperature from ramping up.

Rob R. wrote:I have a few questions that will help sort this out.

1. Did your radiation heat the house properly before you installed the KA-6?
2. What is the high limit setting on the KA-6?
3. Did the boiler reaching the high limit setting during the 5 hour heat call?

If the boiler is reaching the high limit setting and the circulator is running nonstop, it is not a boiler capacity issue.

Rob R. wrote:...when it might be as simple as the Hydrostat control on the Keystoker is set improperly...they have an economy setting that can prevent the boiler temperature from ramping up.

Economy setting? I have a Keystoker KA6, but don't know anything about this economy setting. Is it some new controller? I bought mine used a few years ago.

Thanks.

CoalisCoolxWarm wrote:

Rob R. wrote:...when it might be as simple as the Hydrostat control on the Keystoker is set improperly...they have an economy setting that can prevent the boiler temperature from ramping up.

Economy setting? I have a Keystoker KA6, but don't know anything about this economy setting. Is it some new controller? I bought mine used a few years ago.

Thanks.

If your boiler is a few years old, it probably has a regular Honeywell aquastat.

This is the one I was referring to: http://www.hydrolevel.com/new/images/literature/i ... isphpreq=1

Olllotj wrote:How low did the boiler temp drop?

My thoughts exactly! If boiler is not keeping up with the house, maybe you simply need a little more feed. In the case of my Kaa-2, a little bigger idle fire as well. I'm going to guess a little more feed in your case. Five hours sounds a little long. My Kaa-2 doesn't take that long to heat my house from first fire. Double your attic insulation, and you'll notice a BIG difference. Last I knew, R-38 was code, and code for a reason. However, forget the word code. Not trying to throw codes at you. Add another 6 inches to the attic. You'll notice an immediate difference in heat loss, as well as comfort.

From this thread: Post by Clousseau - Question on Triple Aquastat Adjustment

The dial indicator was set on 1, but I turned it up to 3 to see if I can use less coal.

With a single zone, and the economy setting on #3, the control will keep the boiler about 10 degrees above the low limit setting. I know you guys are all focused on getting more heat out of the stoker, but that might not be the issue at all. Hopefully the original posted will let us know if he figured it out.