Earth Stove MP35/50 Owner's manual

Installation And Operation
Instructions
"linisappliance must be Installed by a qualified technician.
Read thoroughly before installaMon.
Save this manual for future reference.

TABLE OF CONTENTS
Safety Notice ....................................... 1
Introduction ........................................ 2
Operation ........................................--4
Maintenance ......................................- 8
Installation ......................................... 12
Troubleshooting ...................................-18
Power Flow Diagram ............................... 20
Wiring Diagram .................................... 21
Glossary --'- ........ ................................. 22
Specifications ...................................... 23
Component Diagrams .............................. 24
Warranty .......................................... 25
Safety/Listing Label ................................ 26
Service/Maintenance Log ........................... 27
'4
p/n 16482 Rev. 10/97

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•IMPORTANT SAFETY NOTICE
PLEASE READ BEFORE ATTEMPTING TO BURN!
CAUTION: If this stove is not properly installed, a house fire may result For your safety,
follow the installation directions; contact local building officials about restrictions and
installation inspection requirements in your area.
Installation of this stove must comply with
local codes. A building or installation permit
may be required. Be sure to check with your
local building official or fire department
before installing.
11.
If utilizing an existing chimney have your
fireplace flue or chimney system inspected by
a qualified person prior to installation of the
stove. Make any necessary repairs before
installing.
Terminate pellet vent pipe so that contact
with humans or possible damage to pipe is
avoided.
12. Required fuel is: 1/4" diameter wood pellets,
1" ma_cimum length, 8500 BTU per pound,
10% maximum moisture content, 1 1/2% -
3% ash. Corn kernels, 10,000 BTU per
pound, 15% maximum moisture content.
(Optional Cornpot and metering cup filler
plug required).
.
.
D
6.
.
So
.
Never connect stove flue to chimney being
presently used by another appliance.
Never block any air intake or air outlet
ports. Dangerous overheating can result.
Do not install this stove in a sleeping room.
Never connect the stove to an air duct
system.
Never stack or pile combustible materials
against the stove or around external vent
termination.
To avoid burns, children and adults should
be alerted to the hazards of high surface
temperatures.
To provide reasonable fire safety, install a
smoke detector and a conveniently located
fire extinguisher.
13. Do not attempt to burn cordwood or pressed
logs in this stove, severe damage or fire could
result.
Testing/Listing
The Earth Stove model MP35/50 pellet fired
appliance has been constructed, tested and listed
for use in residential construction in accordance
with the applicable portions of the following
standards - UL1482, UL127, UL103 or UL641,
UL507 and UL39i and for use in manufactured
dwellings and park trailers according to OAR
918-520-010 through 918-520-110, by Pacific
Inspection and Research Laboratory, Inc.,
(PIRL) Redmond, WA 98052. Listing file
89-174.
Based on a tested air to fuel ratio in excess of
35:1, this appliance is not an effeeted facility
under the EPA regulations for wood burning
stoves.
10. In the event of a chimney fire, notify the fire
department, and unplug the stove.
Page I

INTRODUCTION Read Entire Manual Before Attempting to Burn
Three Pronged Plug (Grounded) Ash Drawer
Your stove has aprinted circuit board and other
electrical components that require a grounded circuit
and proper polarity. Purchasing a surge protector
provides additional insurance against unnecessary
problems.
Control Panel/Fan Rheostat
The ash drawer located in the front of the pedestal is
designed to make cleaning easier by containing the
ashes in a removable drawer. It is accessed by
turning the spring loaded screws located on the ash
drawer cover. Do not operate the stove with the ash
drawer open or ajar. Replace gasket material as
necessary to insure a tight seal.
The primary control .board manages the performance
of your stove. It allows you to regulate the fuel feed
rate, the draft fan voltage and main power to the
stove. The room air fan rheostat allows you to
manually regulate the fan speed except when the
automatic high speed override is engaged.
Firepot
Decorative Logs
An important feature of your NaturalFire stove is
the realistic fire created by the flame spread firepot
and the refractory logs. Although the logs are quite
durable, they should be handled carefully, as they
retain heat for a considerable period of time, and if
dropped can break.
The pellet firepot is where the fuel is burned.
Although ithas a self cleaning capability for much
of the ash build up, variable fuel quality (ash
content) and extended periods of a low burn rate
will .necessitate some manual cleaning. An Earth
Stox_e firepot cleaning tool is highly recommended
,(part#1000).
Hopper
The hopper is where the fuel is stored before it feeds
into the stove.
Placement of the logs is important in achieving a
realistic fire. One recommended pattern is pictured
below which allows you to use a Firepot cleaner
without having to remove the logs (except for full
maintenance).
Page 2

INTRODUCTION
How It Works
The fuel metering cup rotates in the throat of the hopper
providing a measured amount of fuel based on the set feed
rate. The fuel drops into the anger tube where it is moved
into the firepot. The draf_ f_n provides combustion air
through the _.ger tube and a series of holes in the inner
firepot, to allow for complete combustiom
The flame and hot gases provide heat to the heat exchange
tubes lorm_ in the upper chamber of the stove. The
room air fan extracts the heat and delivers it to the room,
along With the natural radiant heat from the glass and
metal surfaces.
Gold Door
Your Earth Stove's gold door frame should be cleaned
thoroughly With agood window cleaning solution and a
soft cloth BEFORE the stove is burned. Do not use any
metal polishes or abrasives to clean the door. Any oils or
finge_v_ints leg on the gold could become Iw.u_ent
blemishes if the stove is burned prior to _ removal.
Atkrr the first few fires the gold will cure.
Glass
The glass is asuper heat resistant ceramic that withstmds
continuoustemperatums upto 1390° F. This temperature
is well beyond the temperatures in which you operate
your stove.
This appliance is designed to provide aflow of air over
the inmde of the El_% which along with high heat helps
keep it clean. When operating the stove on low for
extended periods of time, the gl___ may get dirty. A
commercial _I_ cleaner designed for stoves is
recommended for cleuning.
The glass should be cleaned thoroughly with glass cleaner
and asoft cloth BEFORE the stove is burned.
Marble Set
Marble is a natural product so each piece will have its
own unique chamc_. Marble may be cleaned With a
damp cloth toremove oils or dust. Be sure toinstallthe
four cerawool strips (under the rfiarble) to protect it Do
notputro_ objects(suchas_vets,steamers,hopperlid,
etc.) on the _. Do not install the marble before
curing the paint
Remote Wall Thermostat
One way to maxim_ the efficiency and convenience of
your stove is to install are.mote wall thermostat. A
Honeywell T87F 24 volt thennostat is recommended (see
page5).
Corn Pot
NaturalFire pellet stoves will bum most types of corn with
the _aa_fion of a corn pot kit. For dtcmils, see the section
on burning com.
Several options are availal, le to enhance your NaturalF'ge pe[l_ stovz Please see your local d..-br for further
inform_m_'_om
Page 3

OPERATION
Before Attempting To Start Your Stove, Read This Manual Thoroughly. Have Your Stove Pretested and
Professionally Installed.
Start Up Procedure
1. Plug in the stove. Fill hopper with pellet fuel.
2. Turn the Main Power Switch to the "Feed
System" position.
3. Provide starting fuel by pushing the "Start
Button" and allow fuel to feed for approximately
five minutes (or put approximately two cups of
fuel directly in the Firepot).
4. Turn the Main Power Switch to the "Off'
position. (This will stop the fuel feed.)
5. Open fire door and apply Fire Starter gel to the
fuel in the Firepot, then light. Allow the fuel to
burn for five minutes with the door slightly ajar.
Shut Down Procedure
1. Turn the Main Power Switch to the "Draft
Fan" position. If using a remote
Thermostat, turn the Thermostat down.
2. When the fire in the Firepot goes out
completely, shut the Main Power Switch to the
"Off" position.
WARNING: IF THE POWER SWITCH IS
TURNED OFF PREMATURELY WHILE A FIRE
IS STILL ACTIVE IN THE FIREPOT, THIS MAY
RESULT IN SMOKE BACK INTO THE
DWELLING (THIS WOULD DISSIPATE
RAPIDLY).
Pellet Fuel Calibration *
6. Close the door.
7. Turn the Main Power Switch to the "Feed
System" position, then push the Start Button.
8. 'Set the Fuel Rate Switch to the "Full" position.
If using a remote Thermostat, adjust it to'the
desired room temperature.
9. As the stove tem]?erature rises, the Room Air
Fan will automaucally engage. At that point,
adjust the Fuel Rate Switch to the desired
setting. During the start up procedure or when
running the stove on a "Low" Fuel Rate Setting,_
the Room Air Fan Rheostat must be in the off
position. Failure to do so could cool down the
stove and it will automatically shut off.
10. If the fire goes out, go back to step two again.
The MP35/50 is shipped from the factory, set to
50,000 BTU input. To adiust to 35,000 BTU input,
install the 1/8" filler plug into the fuel metering cup.
35,000 BTU - 1/8" filler plug
50,000 BTU - open
Filler Plug Installation
Place the filler plug into the bottom of the metering
cup fuel cavity and secure with the screw provided
into the tapped hole.
Page 4

OPERATION
Control Board
A. Main Power Switch
The main power switch is athree way toggle with
the following positions:
1. Off(stove off)
2. Draft Fan -aUows the draft tim to operate
alone during shut down.
3. Feed System -stove on
B. Fuel Rate Switch
The fuel rate switch controls the amount of time
the burner feeds fueL It can be set to the
following threepositions:
o
2.
°
Full -will feed fuelcontinuously.
Medium - will feed fuel approximately
two minutes on then two minutes oE
Low -will feed approximately one
minute on then _ minutes Off..
C. Draft Fan Switch *
The draft fan sSwitoh conlrols the amount of air
used for combustion during piloting process. It
can be set to the following three posifiom:
1. High -runs at 75% of capacity when
stove is not feeding fuel.
2. Low- runs at 50% of capacity when
stove is not feeding fuel.
3. Off- runs at 0°,4 of capacity when stove
is not feedin_ fuel.
*The dmR fan will nm at 100% of capacity
during the feeding of fuel.
D. Start Button
Depress the start button to allow fuel to feed for
approximately 12 minutes (used during start up of
thestove).
E. On/OffLight
The On/Off Light blinks to indicate electricity is
flowing through the primary tonal boar&
F. Fuse
The Fuse protects the Primav/ Control Board
fi_m power "surges or spikes".
Optional Remote Wall Thermostat
One way to maximize the efficiency and convenience of
your stove is to install a icmote wall thermostat. A
Honeywell T87F 24 volt thermostat is recommended.
Follow the m_nuf_etu_s installation insm_ons using
18/2 stat wire. The leads from the stove are the yellow
wires found behind the Primary Control Board.
Once you have installed the Th_m_ostat, the Fuel Rate
Switchshould be set to"Low". This will be the rate the
stove will run on pilot when the Thermostat is not cMllng
for heal
Page 5

OPERATION
Room Air Fan Rheostat
The room air fan rheostat can be used to vary the
speed of the room air fan by rotating it to the
desired setting. When the stove is very hot
(running on high), the rheostat override (fan speed
disc) will automatically run the fan on high to
prevent the stove from overheating.
•"¢
Normal Operating Sounds
Heat Exchange Tubes -As the room air fans
increase in speed, you may hear air flowing through
these tubes and out into the room.
Thermostatic Control Disc - There are four
different heat activated temperature discs on the
insert. The discs can make alight clicking sound as
they cycle while the insert heats up or cools down.
Room Air Fan - The modern, high efficiency fan
may have a hum or pulsating sound, particularly on
the high setting. The sound may change as the fan
speed is varied.
Auger Feed System -When fuel is fed from the
hopper to the auger tube, a light clinking sound of
the fuel being cut may be heard.
Auger/Cup Motor(s) - When feeding fuel, you
may hear the intermittent buT7 or hum of these
motors.
Draft Fan -This motor runs at various speeds to
provide combustion air to the firepot (and to aid in
the draft of the flue). The speed of this motor wiU
,increase with the feeding of fuel.
Page 6

OPERATION
Burning Corn (Optional)
Natural Fire pellet stoves will bum most types of
corn with the addition of a compot kit. Ris not
necessary to mix corn with wood pellets however,
wood pellets are required to start the fire.
NOTE: Burning treated seed corn is never
recommended
The compot kit consists of:
1 1/8" Filler Plug
1 3/8" Filler Plug
1 Compot
To install the cornpot, simply remove the screw(s)
from the top of the auger housing and lift up and out
on the firepot. Slide mounting flange of the cornpot
over the auger housing and replace screw(s).
Initially the air shutter on the draft: fan should be set
at 1/2 open and the draft fan selector on "LOW". If
more or less combustion air is needed, adjust the air
shutter accordingly to achieve a bright yellow flare e.
Because corn size and density varies, it will be
necessary to calibrate the fuel metering cup in order
to maintain rated BTU input and prevent overfiring.
This requires the installation of the filler plug in the
fuel metering cup. Use the 3/8" filler plug provided
in the compot kit.
The moisture content of the corn should be 15% or
less, and care should be taken to ensure that there
are no foreign objects in the corn (i.e. sticks, stalks,
cob parts, etc.). When burning corn, the primary
combustion takes place on a bed at the bottom of the
compot.
The compot has a solid bottom and sides with air
holes because burning corn forms afluid-like
residue which becomes solid when cool. The
cornpot cleaning will depend upon the quality and
quantity of corn being used. The compot should be
cleaned when the build up starts to reach the bottom
air holes inside of the compot. You will need to
remove the ash, and in some instances a white
calcium like deposit. The stove must be shut down
and cooled before cleaning.
CORN BURNING SHOULD BE DONE IN TOP
VENT INSTALLATIONS ONLY. .If the
installation must elbow into a wall thimble, the
horizontal mu sl_ould not be more than 24". The use
of a wall mounted thermostat, part #CTR140 is
suggested.
Start Up Procedure
We recommend starting a corn fire with wood
pellets because corn has adense shell that can be
difficult to start. Manually fill the cornpot, to the
bottom of the auger tube, with wood pellets. Use of
the start button feature is not recommended when
initially starting the unit for corn burning. (See
"Start Up Procedure" in the Operation section for
additional start up information).
Page 7