LAARS Mascot LX MLXC 175 MBH - Install and Operating Manual - Manual (Page 22)

LAARS Heating Systems Page 18
Mascot LX NATURAL GAS REQUIRED
SIZE CU FT / HR INPUT RATE.
50 50
75 75
100 100
125 125
150 150
175 175
220 220
TO SIZE PIPING:
Measure linear distance from meter outlet to last boiler. Add total input of all
boilers and divide by 1000 to obtain cu ft / hr required. Add total equivalent
length of fittings used according to Table 6B. Align total length (pipe and
fittings) on left side column of Table 6C with highest cubic feet of gas required.
NOTES: Consult and confirm with Applicable Fuel Gas Code before
beginning work. Verify gas inlet pressure is between 4 and 13 in W.C.
before starting boiler.
Table 11. Natural Gas Required
EQUIVALENT LENGTHS OF STRAIGHT PIPE FOR TYPICAL SCH 40 FITTINGS
NOMINAL PIPE SIZE
FITTING
1/2" 3/4" 1"
LINEAR FEET
90° ELBOW 3.6 4.4 5.2
TEE 4.2 5.3 6.6
Table 12. Equivalent Pipe Lengths.
Table 13. DHW, Performance Data.
SECTION 5.
Pump Capacity
5.1 Mascot LX Heating System
Pump Capacity
Mascot LX's internal pump is sized for a maximum of 30
ft total equivalent pipe. Laars strongly recommends the
unit to be piped in primary/secondary fashion, or use a
low loss header/hydraulic separator.
Please contact Laars for further application details.
Table 11
DHW Performance Data
At various cold water inlet temperatures
Model: 125
50 60 70
GPM
2 100 97 95
3 79 77 75
4 59 58 56
5 48 46 45
Model: 150
50 60 70
GPM
3 95 92 90
4 71 69 68
6 48 46 45
8 36 35 34
Model: 175
50 60 70
GPM
4 83 81 79
5 67 65 63
6 55 54 53
8 42 40 39
Temp Rise F
Inlet Temp F
Temp Rise F
Inlet Temp F
Temp Rise F
Inlet Temp F
125
150
175
SECTION 6.
Water Connections
6.1 Central Heat System Piping
NOTE: This appliance must be installed in a closed
pressure system with a minimum of 12 psi (82.7kPa)
static pressure at the boiler.
Hot water piping should be supported by suitable
hangers or floor stands. Do not support piping with this
appliance. Due to expansion and contraction of copper
pipe, consideration should be given to the type of hangers
used. Rigid hangers may transmit noise through the
system resulting from the piping sliding in the hangers.
It is recommended that padding be used when rigid
hangers are installed. Maintain 1" (2.5cm) clearance to
combustibles for hot water pipes.
Pipe the discharge of the pressure relief valve (full size)
to a drain or in a manner to prevent injury in the event of
pressure relief. Minimum fill pressure must be 12psig
(82.7kPa). Install shutoff valves where required by code.
CAUTION
PRV (included) must be installed immediately at boiler
outlet with no valves between. Use PRV adapter pipe
(included) for bottom connections or add PRV directly
to the top of boiler with pipe coupling.
__________________________________________
ATTENTION
PRV (inclus) doit être installé immédiatement à sortie
chaudière avec pas de vannes entre. Utiliser le PRV
tuyau adaptateur (inclus) pour les connexions bas ou
ajouter PRV directement vers le haut de la chaudière
avec raccord de tuyau.
__________________________________________
Suggested piping diagrams are shown on the following
pages. These diagrams are meant only as a guide.
Components required by local codes must be properly
installed.