model nomenclature
1,2
3
4
5,6
7
PT
DS BQ
BS
UC
CF
1,2 - Product type (Pt)
MD - 100% Make Up Air
MR - Return Air
3 - design sequence (ds)
B - Internally Assigned
4 - Blower Quantity (BQ)
1 - Single Blower Unit
2 - Twin Blower Unit
5,6 - Blower size (in.) (Bs)
10 - 10"
22 - 22"
12 - 12"
24 - 25" x 22" (single blower units only)
15 - 15"
25 - 25"
18 - 18"
27 - 27"
20 - 20"
30 - 30"
7 - unit configuration (uc) (see Figure 51.1)
A - Horizontal, right access, straight discharge (bottom return on MR)
B - Horizontal, left access, straight discharge (bottom return on MR)
C - Horizontal, right access, bottom discharge (bottom return on MR)
D - Horizontal, left access, bottom discharge (bottom return on MR)
E - Horizontal, right access, top discharge (not available on MR units)
F - Horizontal, left access, top discharge (not available on MR units)
G - Vertical, right access, top discharge (not available on MR units)
J - Vertical, right access, top-right discharge (not available on MR units)
8 - cabinet Finish and location of installation (cF)
A - Unpainted, Outdoor Installation
B - Unpainted, Indoor Installation
C - Painted, Outdoor Installation
D - Painted, Indoor Installation
9, 10, 11, 12 - maximum Burner input (mBh) (mBtu)
0275
3850
0400
4125
0550
4400
0825
4675
1000
4950
Example: If burner rating is 389MBH,
1100
5225
0400 will be used in model number.
1375
5500
1650
5775
1925
6050
2200
6325
2475
6600
2750
6875
3025
7150
3300
7425
3575
13 - Gas type and inlet Pressure
A - Natural Gas (8-14")
B - Natural Gas (1-5 psi)
C - Propane Gas (11-14") (Model MDB Only)
D - Propane Gas (1-5 psi) (Model MDB Only)
Figure 47.1- unit configurations j
2
A = HRS
2
C = HRB
Denotes direction of air flow
j Configurations are shown facing the side of the unit with the gas and electrical controls.
k For models with return air (Series MRB).
8
9,10,11,12 13
14
15
MBTU
GT
GC
I
E = HRT
2
B = HLS
16
17
18
19
20
MO
AC
SV
BT
HP
MT
14 - Gas control system (Gc)
A - Maxitrol 14
B - Maxitrol 44
C - SC11 DDC (4-20 mA)
D - SC11 DDC (0-10 VDC)
15 - insurance (i)
1 - IRI (standard ETL)
2 - FM less Restriction
3 - FM with Restriction
16 - additional manifold options (mo)
C - High & Low Gas Pressure Switch
N - None
17 - air control option (ac)
A - 100% MUA - Single Speed
B - 100% MUA - Two Speed (Motor or VFD) - Type A
C - 100% MUA - Two Speed (Motor or VFD) - Type B
D - 100% MUA - DDC Control (VFD only) - Type A
E - 100% MUA - DDC Control (VFD only) - Type B
F - Space Pressure Control (MD with VFD or MR) - Type A
G - Space Pressure Control (MD with VFD or MR) - Type B
H - Space Pressure Control (MD with VFD or MR) - Type C
I - Return Air - Fixed 75/25 Dampers - Type A
J - Return Air - Fixed 75/25 Dampers - Type B
K - Return Air - Fixed 75/25 Dampers - Type C
L - Return Air - Fixed 70/30 Dampers - Type A
M - Return Air - Fixed 70/30 Dampers - Type B
N - Return Air - Fixed 70/30 Dampers - Type C
18 - supply voltage (sv)
1 - 115/60/1
2 - 208/60/1
3 - 230/60/1
4 - 208/60/3
19 - Bearings and vibration isolation (Bt)
A - Spider Bearings - No Vibration Isolation
B - Pillow Block Bearings - No Vibration Isolation
C - Pillow Block Bearings - With Spring Vibration Isolation
20 - motor hP (hP)
A - 3/4
B - 1
C - 1.5
D - 2
E - 3
F - 5
G - 7.5
21 - motor type (mt)
1 - ODP
2 - ODP - High Efficiency
5 - TE
6 - TE - High Efficiency
22 - sheave arrangement (sa)
A - (see Sheave Tables)
23 - Profile assembly (Pa)
A - (Internally assigned)
F = HLT
2
D = HLB
7-500.10
21
22
23
SA PA
5 - 230/60/3
6 - 460/60/3
7 - 575/60/3
H - 10
I - 15
J - 20
K - 25
L - 30
M - 40
N - 50
G = VTS
J = VTR
47