Gas Pressure - Superior Fireplaces DRT3500 Series Installation And Operation Instruction Manual

Innovative Hearth Products
DRT3500 Series Direct-Vent Gas Fireplaces
BTU Input
Table 1 - Input Rate (BTU/HR), Gas Valves
Table 2 - Thermal Efficiency (%)
* AFUE is a measurement of the US Department of Energy,
** Complies with CSA P.4.1-2015 "Testing Method for Measuring Annual Fireplace Efficiency. P4 (EnerGuide) is a measurement of the
Canadian Office of Energy Efficiency.
Efficiencies are based on Normal input operation.

Gas Pressure

Table 3 - Inlet Gas Supply Pressure
Fuel
Natural Gas
Propane
The high and low manifold test gauge connections are provided on the stem of the electronic gas valve (see Figure 1A).
The inlet line gas pressure test point is shown in Figure 1B. The control valves have a 3/8" (10 mm) NPT thread
inlet and outlet side of the valve.
Figure 1A Figure 1 - MANIFOLD Outlet Gas Pressure Test Point
Outlet Pressure
Test Point
Ecoflow
Figure 1B - INLET Line Gas Pressure Test Point
Testing Inlet Line Gas Pressure (Qualified Technicians
Only):
1. Turn off gas shutoff valve and electrical.
2. Remove 1/8" plug (shown in diagram to the right).
3. Install an 1/8" nipple in place of plug.
4. Connect manometer to nipple, using an 1/8" NPT air
hose nipple/fitting.
5. Turn on shutoff valve and check for proper inlet gas
pressure.
6. Reverse steps 1-5.
Models
35" Models
40" Models
45" Models
Model
AFUE *
35" Models
40" Models
45" Models
Minimum
5" WC / (1.25 kPa)
11.0" WC / (2.74 kPa)
Inlet Pressure
Test Point
Natural Gas
High Rate Low Rate
20,000 14,000
24,000 17,000
28,000 18,500
Electronic
P4 **
66 64
66 64
67 65
Maximum
10.5" WC / (2.61 kPa)
13.0" WC / (3.23 kPa)
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.
Some parts have been removed for clarity
1/8" Inlet line gas pressure 'test point' plug (in control compartment)
900683-01F, 10/2018
Propane Gas
High Rate
19,000
22,000
26,000
Based on CSA P.4.1-2015
Table 4 - Manifold Gas Supply Pressure
Fuel
Natural Gas 3.5" WC / (0.87 kPa)
Propane 10.0" WC / (2.49 kPa)
General Information
Low Rate
13,000
17,000
20,000
Pressure
9