Indoor Fireplace User Manual
7
NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.
BTU Input
These fireplaces are designed as supplemental 
heaters. Therefore, it  is advisable  to have an 
alternate  primary heat  source  when  installed 
in a dwelling.
Millivolt Models - The millivolt appliances are 
manually controlled and feature a spark igniter 
(piezo) that allows the appliance's pilot gas to 
be lit without the use of matches or batteries.  
This system provides continued service in the 
event of a power outage.
Millivolt models come standard with a manu-
ally-modulated gas valve; flame appearance and 
heat output can be controlled at the gas valve. 
The BTU Input for these appliances is shown 
in Table 1.
Electronic Models - Electronic models have a 
fixed rate gas valve.  Input of electronic models 
is shown in Table 1.
Burn-in Period
During the first few fires of this appliance there 
will  be  some  odor  due  to  the  curing of  the 
paint and burning off of lubricants used in the 
manufacturing process.   Depending  on your 
use, the burn-in period may take a few hours 
or a few days. 
KEEP  YOUR  HOUSE  WELL  VENTILATED 
DURING THE CURING PROCESS.  THE ODOR 
AND  HAZE  EMITTED  DURING  THE  CURING 
PROCESS CAN BE QUITE NOTICEABLE AND 
MAY SET OFF A SMOKE DETECTOR.
If an optional blower is installed, Do Not turn 
it on during the Burn-In period. 
A white film may develop on the glass front 
during the first few fires as part of the curing 
process.  The glass should be kept clean during 
the first two weeks of use to prevent the film from 
baking on (making it very difficult to remove).  
See Cleaning Glass on Page 10
Test gauge connections are provided on the 
front of the millivolt and electronic gas control 
valve (identified IN for the inlet and OUT for the 
manifold side). The control valves have a 3/8" 
(10mm) NPT thread inlet and outlet side of the 
valve (refer to Figures 1 and 2).
Propane tanks are at pressures that will cause 
damage to valve components. Verify that the 
tanks have step down regulators to reduce the 
pressure to safe levels.
These appliances must not be connected to a 
chimney or flue serving a separate solid fuel 
burning appliance.
Orifice Sizes - Sea Level to High Altitude
(All Models)
These appliances are tested and approved for 
installation at elevations of 0-4500 feet (0-1372 
meters) above sea level using the standard burner 
orifice sizes (marked with an "*" in Table 4 ).
For elevations above 4500 feet, contact your gas 
supplier or qualified service technician. 
Manifold Gas Supply Pressure
(all models)
Fuel # Low High
Natural 
Gas
(Lo) 2.2" WC
(0.55 kPa)
(Hi) 3.5" WC
(0.87 kPa)
Propane
(Lo) 6.3" WC
(1.57 kPa)
(Hi) 10.0" WC
(2.49 kPa)
Table 3
These appliances must be isolated from the 
gas supply piping system (by closing their 
individual manual shut-off valve) during any 
pressure testing of  the  gas  supply piping 
system at test pressures equal to or less 
than 1/2 psig (3.5 kPa).
These appliances and their individual shut-off 
valves must be disconnected from the gas 
supply piping system during any pressure 
testing of that system at pressures greater 
than 1/2 psig (3.5 kPa).
Inlet Gas Supply Pressure 
(all models)
Fuel # Minimum Maximum
Natural Gas
4.5" WC
(1.12 kPa)
10.5" WC
(2.61 kPa)
Propane
11.0" WC
(2.74 kPa)
13.0" WC
(3.23 kPa)
Table 2
Gas Pressure - All Models
Tables 2 and 3 show the appliances' inlet and 
manifold gas pressure requirements:
Deration - At higher elevations, the amount of 
BTU fuel value delivered must be reduced by 
either using gas that has been derated by the gas 
company or by changing the burner orifice to a 
smaller size as regulated by the local authorities 
having jurisdiction and by the (USA) National 
Fuel Gas Code NFPA 54/ANSI Z223.1 - latest 
edition or, in Canada, the  CAN/CSA-B149.1 
codes - latest edition.
Install the appliance according to the regulations 
of the local authorities having jurisdiction and, 
in the USA, the National Fuel Gas Code NFPA 
54 / ANSI Z223.1 - latest edition or, in Canada, 
the CAN/CSA-B149.1 - latest edition.
Flame breadth, height and width will dimenish 
4% for every 1,000 feet of altitude.
Burner Orifice Sizes (all models)
Elevation
Feet (meters)
Natural
Gas
drill size (inches)
Propane
Gas
drill size (inches)
0-4500
(0-1372)
#37 (0.104") 
*
24M10•
1.55 
mm 
(0.061")
*
42M79•
Table 4
* Standard size installed at factory
 • Part /Cat. Number
 Input (BTU) Gas Valves (all models)
Models Fuel 
Type
Input Rate
(BTU / HR)
MPD35ST/PF-NM
(Millivolt)
Natural
30,000 high
23,000 low
MPD35ST/PF-PM
(Millivolt)
(if field converted)
Propane
28,000 high
22,000 low
MPD35ST/PF-NE
(Electronic)
Natural 30,000
MPD35ST/PF-PE
(Electronic)
(if field converted)
Propane 28,000
Table 1










