Roberts Gorden CRV-B-4 - Manual (Page 38)

CRV-S ERIES D ESIGN M ANUAL
32
SECTION 11: CRV-SERIES EQUIPMENT SPECIFICATIONS
The total heating system supplied shall be design cer-
tified by the CSA International per American National
Standard ANSI Z83.20/CSA 2.34 (latest edition).
11.1 Burner and Burner Controls
11.1.1 Burners shall be designed to operate simulta-
neously in series without adverse effects from com-
bustion gases from upstream burners.
11.1.2 Burners shall be capable of firing on:
Natural Gas, or LP Gas.
11.1.3 Burners shall be supplied to fire at any one of
the input firing rates as specified:
CRV-B-2-20,000 (Btu/h)
CRV-B-4-40,000 (Btu/h)
CRV-B-6-60,000 (Btu/h)
CRV-B-8-80,000 (Btu/h)
CRV-B-9-90,000 (Btu/h)
CRV-B-10-100,000 (Btu/h)
CRV-B-12A-110,000 (Btu/h)
CRV-B-12-120,000 (Btu/h)
When using ROBERTS GORDON ® ULTRAVAC ™ con-
trols, burner rates will modulate between 60% and
100% rated input (CRV-B-2 and CRV-B-4 are not avail-
able for use with ROBERTS GORDON
® ULTRAVAC ™
controls).
11.1.4 The design of burners supplied shall provide
for maintaining a constant proportion of fuel gas to fil-
tered combustion air. These conditions are met for
burners in which the pressure of both the fuel gas
and the combustion air are introduced at zero (atmo-
spheric) pressure and the flow of each is established
by a vacuum on the downstream side of the flow
metering orifices.
11.1.5 To assure a high degree of fail-safe operation,
the design shall preclude flow of gas if any or all of
the following abnormal conditions occur in the non-
firing mode:
1. Main valve fails in open position.
2. Vacuum pump motor fails to operate.
3. Power fails.
11.1.6 To further assure a high degree of safety, the
system will be under negative pressure at all times
during operation to preclude the possibility of the
escape of combustion gases inside the building.
11.1.7 The burner control assembly will include a zero
regulator.
11.1.8 All burners shall be pre-wired with a grounded
electrical cord and plug.
11.2 Equipment
11.2.1 Burner
Each burner assembly shall consist of heavy-duty
cast-iron burner heads, pre-wired gas controls with
electronic, three-try direct spark ignition and combus-
tion air filter.
11.2.2 Pump
The pump model supplied will vary with the capacity of
the system. See the pump technical specification
sheet or the installation, operation and service manual
for product description and specification.
The pump shall be acoustically isolated from the sys-
tem with a flexible connector with temperature rating of
350°F minimum. The motor in the vacuum pump shall
be secured with rubber mounts for acoustical isolation.
11.2.3 Heat Exchanger
Radiant tubing (between burners and 10’ - 70’ down-
stream of last burner) shall be of 4" O.D. steel or heat
treated aluminized tubing.
As an option, the balance of the tubing shall be 4"
O.D. steel tubing with an internal and external coating
of acid-resistant porcelain.
All heat exchanger (tubing) connections shall be made
with stainless steel coupling assemblies. Standard
couplings will be used in radiant sections. Lined cou-
plings will be used in tailpipe sections.
11.2.4 Outside Air
When specified, in contaminated environments, the
system shall be capable of supplying air from the out-
side to each burner and end vent for the support of
combustion.