| Supplementary Heating and Cooling Although the VHR recovers most of the exhaust energy, it is usually necessary
to provide supplementary heating or cooling in order to satisfy the room thermostat.
A variety of factory and field installed options are available to
provide the supplementary heating and cooling needed for most installations.
Required capacity and engineering data is shown in the tables that
follow. Dimensions of field installed heaters or coils will be furnished on request.
HEATING - Factory installed
in VHR
Steam or Hot Water Coils
| VHR Model Size |
SCFM Range |
Maximum Coil Size
(Inches) |
Coil Face Area (Sq.
Ft.) |
| 2 thru 5 |
200 thru 5000 |
18 x 36 |
4.5 |
| 5X thru 9 |
5000 thru 9000 |
24 x 48 |
8.0 |
| 8X thru 14 |
8000 thru 14000 |
30 x 60 |
12.5 |
| 13X thru 18 |
13000 thru 18000 |
36 x 72 18.0 |
|
Note: Coils are factory mounted and piped down
through drain pan. Steam or hot water valves and motors can be furnished for field piping
and wiring. Coils can be controlled either by space thermostat or discharge air
controller. Contact factory for capacity and pressure drop information.
Electric Heater
| Electric Heater Size |
VHR Model Size |
SCFM Range |
Minimum |
Maximum |
| KW |
MBH |
Pressure Drop " w.c. |
KW |
MBH |
Pressure Drop " w.c. |
| EC-5 |
2 thru 5 |
2000 thru 5000 |
6 |
20.5 |
.06 |
100 |
341.2 |
.25 |
| EC-9 |
5X thru 9 |
5000 thru 9000 |
16 |
54.6 |
.10 |
175 |
597.1 |
.25 |
| EC-14 |
8X thru 14 |
8000 thru 140000 |
25 |
85.3 |
.12 |
290 |
989.5 |
.25 |
| EC-18 |
13X thru 18 |
13000 thru 18000 |
41 |
139.9 |
.15 |
390 |
1330.7 |
.25 |
Note: UL listed electric heaters are factory
installed and wired complete with temperature controls. up to 10-steps of modulation is
available and can be controlled either by space thermostat or discharge air controller.
See Bulletin SBE-1 for electric heater specifications.
HEATING - Field installed in
ductwork
INDIRECT FIRED
Indoor Gas Duct Furnace
For Natural Gas or Propane
| Model |
MBH Output |
Minimum |
Maximum |
| SCFM |
T.R. F |
Pressure Drop " w.c. |
SCFM |
T.R. F |
Pressure Drop " w.c. |
| DU-50 |
37.5 |
350 |
100 |
.10 |
1735 |
20 |
.31 |
| SD-100 |
78.0 |
725 |
100 |
.08 |
3615 |
20 |
.29 |
| SD-120 |
93.6 |
870 |
100 |
.08 |
4335 |
20 |
.29 |
| SD-160 |
124.8 |
1155 |
100 |
.08 |
5780 |
20 |
.29 |
| SD-215 |
167.7 |
1555 |
100 |
.06 |
7765 |
20 |
.23 |
| SD-255 |
198.9 |
1845 |
100 |
.06 |
9210 |
20 |
.23 |
| SD-300 |
234.0 |
2170 |
100 |
.06 |
10435 |
20 |
.23 |
| SD-400 |
304.0 |
2415 |
100 |
.06 |
14075 |
20 |
.23 |
Note: Multiple identical furnaces may be
combined for greater heating capacity. See Bulletin SD-1 for additional information.
Rooftop Gas Duct Furnace
For Natural Gas Or Propane
| Model |
MBH Output |
Minimum |
Maximum |
| SCFM |
T.R. F |
Pressure Drop " w.c. |
SCFM |
T.R. F |
Pressure Drop " w.c. |
| RD-100 |
76.0 |
705 |
100 |
.06 |
3520 |
20 |
.27 |
| RD-125 |
95.0 |
880 |
100 |
.06 |
4400 |
20 |
.27 |
| RD-160 |
121.6 |
1130 |
100 |
.06 |
5630 |
20 |
.27 |
| RD-210 |
159.6 |
1480 |
100 |
.06 |
7390 |
20 |
.27 |
| RD-250 |
190.0 |
1760 |
100 |
.06 |
8800 |
20 |
.27 |
| RD-300 |
228.0 |
2115 |
100 |
.06 |
10555 |
20 |
.27 |
| RD-400 |
304.0 |
2815 |
100 |
.06 |
14075 |
20 |
.27 |
Note: Use prefix "RDG" for gravity
vent and "RDV" for power vent. Multiple identical furnaces may be combined for
greater heating capacity. See Bulletin RD-1 for additional information.
OIL OR GAS/OIL: Contact Factory
DIRECT FIRED
Model SBDF Direct Gas-Fired Duct Furnace
When using a direct gas-fired burner as supplementary heat it is
often recommended that a SBD unit with blower and burner be transitioned to the heat
recovery unit. The VHR is located upstream of the SBD unit and is furnished less supply
blower. This has the advantage of the direct gas-fired burner being located on the suction
side of the blower avoiding stratification of the heated air. See Bulletin SBD-1 for
complete information on the SBD unit.
Model SBD Direct Gas-Fired Unit.
Both weatherproof and indoor direct gas-fired duct furnaces are
available in a wide range of sizes and capacities. All electric and safety controls can be
furnished with these duct furnaces that are available with the SBD units. See Bulletin
SBD-1 for details.
COOLING - Factory or Field
installed
Direct expansion and chilled water cooling coils are
available. Contact factory for complete details. |
