HearthStone Quality Home Heating Products, Inc ®
2
WFP-75 Model 8411
Notes on Fireplace Operation and Efficiency
Rating:
You have purchased a HearthStone WFP-75 tested and certified in compliance with CFR 40 part 60, subpart AAA, section
60.534(a)(1(ii) and ASTM E3053-17. This fireplace is certified to comply with the U.S. Environmental Protection Agency
2020 particulate emissions standard using cord wood. It is certified at 1.14 g/hr emission rate and under specific test
conditions has been shown to deliver heat at rates ranging from 14,200 to 48,200 BTU/hr (output).
This wood heater has a manufacturer-set minimum allowable low burn rate that must not be altered. It is against federal
regulations to alter this setting or otherwise operate this wood heater in a manner inconsistent with operating instructions in
this manual.
Please refer to the Warranty section of this manual for registration instructions. In case of warranty claims, please contact
the point of original sale or the nearest authorized HearthStone dealer. All warranty claims are processed by our dealer
network. Authorized HearthStone dealers can be located at
This heater is designed to burn natural wood only. Higher efficiencies and lower emissions generally result when burning
air dried seasoned hardwoods, as compared to softwoods or to green or freshly cut hardwoods.
DO NOT BURN:
Garbage, lawn clippings, material containing rubber (including tires), materials containing plastic, waste petroleum products
paints or paint thinners, asphalt products, materials containing asbestos, construction or demolition debris, railroad ties,
pressure treated wood, manure or animal remains, salt water driftwood or other previously salt water saturated materials,
unseasoned wood, paper products, cardboard, plywood or particleboard.
This prohibition against burning these materials
does not prohibit the use of fire starters made from paper, cardboard, saw dust, wax and similar substances for the
purpose of starting a fire in an affected wood heater. Burning these materials may result in a release toxic fumes or render
the heater ineffective and cause smoke.
Following the maintenance guidelines set forth in this manual will help insure the efficient use of your wood heater and
minimize visible emissions. Having your fireplace inspected by a trained professional on a regular basis will greatly
increase the potential for recognizing potential impacts to efficiency.
Proper draft is important to the efficient operation of your heater. Refer to the Normal Operation section of this manual for
information regarding adequate draft. Both excessive and sub-minimum draft can affect the efficiency of your wood heater.
Excessive draft can lead to over-consumption of fuel, lower overall heating capacity of the fireplace and potential over
firing. Low draft can result in inefficient burns, low heat output, expulsion of smoke into the living area when fireplace doors
are opened and an increased potential for build-up of flammable materials in the flue.
Efficiency:
Efficiency was captured using CSA B415-10 methodology. A weighted average was used to calculate the overall efficiency
across all of the 3 burn rate categories using the higher heating value (HHV). The weighted average efficiency for the
WFP-75 8411 is 68% (HHV).
To maximize the efficiency of your wood fireplace make sure it is sized properly for the space you plan to heat. An
oversized fireplace will often be forced to burn at a lower and dirtier burn rate. Consult with your dealer for sizing and
correctly placing the fireplace in your home. An incorrectly placed fireplace can greatly reduce efficiency. Maximizing the
efficiency of your fireplace will heat your house quickly, burn cleaner and use less wood.
Refer to the Choosing Firewood section of this manual for appropriate fuel selection. Seasoned firewood is typically at or
near 20% moisture content. This can be measured with any number of hand-held moisture meters available through your
local hearth shop. Follow instructions included in the meter you purchase to measure fuel wood moisture content. Burn
only dry, seasoned wood as using wet wood will greatly reduce your efficiency.
CO Emissions:
The WFP-75 has an average CO emission rate of 53 g/h. Wet wood or unapproved fuel described above can greatly affect
the emissions of a wood burning fireplace.
Smoke/Fire/CO Detectors:
It is highly recommended that smoke and CO detectors be installed throughout the heated space when a wood burning
heater is installed. Be certain to install these devices not only in the area where the wood appliance is located, but also
in bedrooms, hallways leading to other areas of the house and all common areas of the heated space. Check the
batteries in these devices and assure operation by performing whatever test operations are recommended by the
manufacturer.
