Mod Con MODCON500, Installation Manual

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LP-446-r4 Rev. 10.12.16
30
I. Condensate Removal System
NOTE: Check with your local gas company to determine if
combustion condensate disposal is permitted in your area. In
the state of Massachusetts, condensate must be neutralized
before entering a drain.
This boiler is a high efficiency appliance, and therefore
produces condensate: a by-product of the combustion
process. A condensate collection system with an internal
float switch monitors condensate level to prevent it from
backing up into the combustion system. There is a ¾” socket
connection provided to connect the outlet of the collection
system to a drain or condensate pump.
Condensate from the boiler is slightly acidic with a pH of 3.2 -
4.5. To avoid long term damage to the drainage system and to
meet local code requirements, HTP recommends neutralizing
condensate with a Condensate Neutralizer Kit (Part # 7350P-
611). The neutralizer kit connects to the drain system and
contains limestone chips that neutralize the pH level of the
condensate. The neutralizer kit should be checked annually
and the limestone chips replenished if necessary. When
replacing the limestone chips, take care to ensure chips are no
smaller than ½” to avoid blockage in condensate piping (refer
to figure below for piping of the condensate neutralizer.)
Figure 24 - Condensate Piping
NOTES:
1. Condensate line must be pitched at least ¼” per foot to
properly drain. If this cannot be done, or a very long length
of condensate hose is used, increase the condensate line
to a minimum of 1” ID and place a tee in the line after the
condensate neutralizer to properly reduce vacuum lock in the
drain line.
Under no circumstances should the mechanical room ever
be under negative pressure. Particular care should be taken
where exhaust fans, attic fans, clothes dryers, compressors, air
handling units, etc., may take away air from the unit. Failure
to follow these instructions could result in property damage or
personal injury.
Combustion air supply must be completely free of any
flammable vapors that may ignite, or chemical fumes which may
be corrosive to the boiler. See Table 3 for a list of combustion
air contaminants. These chemicals, when burned, form acids
which quickly attack the stainless steel heat exchanger, headers,
flue connectors, and the vent system. The result is improper
combustion and premature boiler failure. Such failure IS NOT
covered under warranty.
EXHAUST FANS: Any fan or appliance which exhausts air from
the mechanical room may deplete the combustion air supply
and/or cause a downdraft in the venting system. Spillage of flue
products from the venting system into an occupied living space
can cause a very hazardous condition that must be corrected
immediately.
Minimum Recommended Combustion Air Supply to
Mechanical Room
Model
Figure 20 Figure 21
*Outside Air from 2
Openings Directly
from Outdoors
1
*Outside Air from 2
Ducts Delivered from
Outdoors
1
Top
Opening,
in
2
Bottom
Opening,
in
2
Top
Opening,
in
2
Bottom
Opening,
in
2
500
125 125 250 250
700 175 175 350 350
850
215 215 425 425
Model
Figure 22 Figure 23
Inside Air from 2 Ducts Delivered
from Interior Space
2
*Outside
Air from 1
Opening
Directly
from
Outdoors,
in
2 1
Same Story
Different
Stories
Top
Opening,
in
2
Bottom
Opening,
in
2
Top
Opening,
in
2
500
500 500 1000 170
700
700 700 1400 235
850
850 850 1700 285
Table 13 - Indoor Combustion Air Sizing
The above requirements are for the boiler only; additional gas fired
appliances in the mechanical room will require an increase in the net
free area and/or volume to supply adequate combustion air for all
appliances.
No combustion air openings are needed when the boiler is installed in
a space with a volume NO LESS than 50 cubic feet per 1,000 BTU/hr
of all installed gas fired appliances. Buildings MUST NOT be of *”Tight
Construction”.
1
Outside air openings shall communicate with the outdoors.
2
Combined interior space must be 50 cubic feet per 1,000 BTU/hr input.
Buildings MUST NOT be of *”Tight Construction”.