Part number 550-143-010/1021
16
GV90+
series
2
gas-fired water boiler – boiler manual
Figure 17
Baseboard system — circulator zoning
MINIMUM
Boiler loop pipe
size
GV90+3/4
GV90+5/6
1”
1¼”
Baseboard system piping —
CIRCULATOR zoning (primary/secondary)
Apply Figure 17 for circulator zoning on systems using baseboard heaters.
The heaters can be any baseboard style, including finned tube or cast iron.
Zoning with circulators
— The GV90+ internal system
circulator cannot be removed from the boiler for use as
one of the zone circulators. It must remain as shipped from
the factory to allow proper flow control inside the boiler.
You will need a circulator for each zone. Provide circulator
relays or circulator zone controller.
Baseboard system piping —
ZONE VALVE zoning (direct connection)
The boiler internal circulator can be used to circulate many zone-valve
zoned systems as shown in
for application on systems
using baseboard (finned tube or cast iron).
•
DO NOT apply this piping when using a GV90+6 — the internal
circulator cannot supply enough flow to the system
.
•
When applying
DO NOT exceed the limits
shown in
•
For systems requiring higher flow or head loss, apply the
suggested piping of
.
Balancing, when required
—
Substitute a memory-stop
valve for one of the isolation valves in each zone to use the
memory-stop valve for balancing flow as well as isolation.
Zoning with zone valves
—
Provide a separate 24-volt
transformer to power the zone valves. Size the transformer
to handle the total rated load of all connected zone valves.
Alternatively, use a zone valve zone controller.
Do not use R & C connections for zone valve.
DO NOT connect directly from 3-wire zone valves
to the T-T terminals on the boiler
. When using 3-wire
zone valves, install an isolation relay. Connect the zone
valve end switch wires to the isolation relay coil. Connect
the isolation relay contact across the boiler T-T terminals.
Failure to comply can result in damage to boiler components
or cause unreliable operation, resulting in severe property
damage.
1.
and
provide guidelines for check-
ing whether the GV90+ internal circulator can provide sufficient flow
when directly connected to a two-pipe baseboard system.
The outputs of GV90+ boilers are all too high for connection
to a single-loop series-loop system. To apply to an existing
series loop system, the system must be fitted with trunk lines
to convert to a split-loop system. Provide either one or two
trunk lines to meet the minimum number of circuits and
maximum loading per circuit given in
2. The system pipe sizing must be no smaller than shown in the Legend
.
3. Values shown for maximum circuit lengths, maximum load per circuit
and the maximum feet baseboard per circuit are limits that ensure
the internal circulator will have sufficient head to provide the flow
needed for each circuit.
Install water piping
(continued)
Legend
1 Isolation valves
2 Automatic air vent (with
diaphragm-type expan-
sion tank), or connect to
tank fitting (closed-type
expansion tank).
3 Diaphragm- or bladder-
type expansion tank, if
used. (For closed-type
expansion tank, pipe
from top of air separa-
tor to tank fitting as in
.)
5 Zone circulator
6 Flow/check valve
7 Hose bibb purge valve
8 Boiler pressure/tempera-
ture gauge
16 Cold water fill line — see
for
typical components