Roberts Gorden 100 User Manual

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For vent termination 

See Page 14, Figure 8 through 

Page 18, Figure 13.

The vent must be fitted with a low resistance 
terminal. 

See Page 14, Figure 8 through Page 16, 

Figure 10. Standard vented heaters do not allow 
outdoor air intake for combustion air.

The heaters are designed to be installed as 
separated combustion heaters. The vent and air 
intake are run as separate pipes to the wall or roof 
terminals. 

See Page 17, Figure 11. As an option, the 

vent and air intake are run as separate pipes to a 
concentric vent box and a concentric vent/air intake 
pipe penetrates the wall or roof. 

12 and Page 18, Figure 13.
For separated combustion installation, the vent and 
air intake must be fitted with an individual and 
correctly sized sealed system and the vent and air 
intake must terminate at approved wall and roof 
terminals.

Separated combustion units may not be common 
vented. 

See Page 12, Section 7.

This heater is not approved to be installed in 
residential buildings.

For unvented operation in commercial installations, 
sufficient building ventilation must be provided in the 
amount of 4 cfm per 1000 Btu/h firing rate (United 

States); 3 cfm per 1000 Btu/h firing rate (Canada).

Horizontally vented heaters must be individually 
vented.

Vent pipe must be sloped ¼" (.6 cm) downward for 
every 1' (.3 m). For vent lengths greater than 5' (1.5 
m), condensation will form. Insulation is 
recommended and condensation drains may be 
desired.

In noncombustible walls only, vent terminal 
(P/N 02537801-1P) may be used.

For 4'' (10 cm) vents in either combustible or 
noncombustible walls, use vent terminal (P/N 
90502100) or equivalent insulated vent terminal. 
Follow the manufacturer's instructions for proper 
installation.

Instead of an insulated vent terminal, a listed thimble 
with 2" (5 cm) air gap may be used with a 4" (10 cm) 
vent cap (P/N 90502102).

Vertically-vented standard-vented heaters can be 
common vented (up to four heaters). 
For vent lengths greater than 5' (1.5 m), 
condensation will form. Insulation is recommended 
and condensation drains may be desired. Venting 
through the top of the heater cabinet is not 
recommended if vent lengths are longer than 
10' (3 m). In this case, vent from the rear of the 
heater cabinet then run the vent vertically and use a 
condensate drain at the bottom of the vertical vent.
Vent pipe must be sloped 1/4'' (.6 cm) for every 
1' (.3 m).

For 4'' (10 cm), an approved vent cap
(P/N 90502102) must be used.

For 6'' (15 cm) common vent, an approved vent cap 
(P/N 90502103) must be used.

For common vertical venting of more than two 
heaters, 

See Page 16, Figure 10.

A vent shall not extend less than 2' (.6 m) above the 
highest point where it passes through a flat roof of a 
building. 

If using vent lengths greater than 5' (1.5 m), 
condensation will form in the vent pipe. Insulation 
and additional sealing measures (high temperature 
silicone at all seams) are required. 
The entire vent should be insulated with foil faced 
fiberglass insulation (1/2" thick, 1-1/2# density 
minimum).