ClimateMaster Trilogy Q-Mode (QE) Series, Руководство пользователя

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c l i m a t e m a s t e r.c o m
Trilogy
®
Q-Mode
®
(QE) Series IOM - 60Hz HFC-410A
R e v i s e d : D e c e m b e r 2 2 , 2 0 2 1
Multiple Unit Piping and Flushing (Cont.)
Multiple Units with Internal Flow Controllers
The simplest multiple unit system is one with two (or more)
units utilizing internal Flow Controllers with no external
pumps or flushing valves. In this case the units are piped
in parallel and use the internal flushing valves to flush the
system. The variable speed pump includes an internal check
valve to prevent back (short circuiting) flow through the units.
In this case, flush the loop through the internal flushing
valves in the unit farthest from the loop first. Once the loop is
flushed, change the internal flushing valves to flush the heat
pump and loop together. Next, move the flushing cart to the
next closest unit to the loop.
Again, flush the loop through the internal flushing valves.
This is important as there may be air/debris in the lines from
this unit to the common piping. Once flushing begins the air
will be move into the loop and will need to be flushed out.
After the loop is flushed through the second unit, change the
flushing valves to flush the second unit and the loop. This
process should be repeated for additional units working from
the farthest from the loop to the closest to the loop.
This type of application can generally be employed for
systems to 12 tons depending on loop design. However, it
is important perform appropriate calculations to confirm that
the variable speed pump can provide adequate flow through
all heat pumps against the loop head when all units are
operating.
Multiple Units with Internal Flow Controllers and External
Flushing Valves
When the number of units or flushing requirements reaches
a point where it is no longer feasible to flush through the
internal valves (generally systems of more than 12 tons
depending on loop design), external flushing valves should
be installed. In this case, three-way flushing valves should
be used or additional isolation valves must be installed to be
able to isolate the loop during flushing.
First, flush the ground loop. The installer should close the
indoor loop shut-off valve (or the internal flushing valves in all
units) and open the ground loop shut-off valve to prevent flow
through the indoor loop while flushing the ground loop.
Once the ground loop is flushed, close the ground loop shut-
off valve and open the indoor loop valve(s) to flush the units
and indoor piping. Remember that there is an internal check
valve in the variable speed pump and that backward flow the
unit is not possible.
Multiple Units with Internal Flow Controllers
Water Out
Water In
Heat Pump
B
Water Out
Water In
Heat Pump
A
To Ground
Loop
Size for Heat Pump
‘A’ Flow
Size for Heat Pump
‘B’ Flow
Size for ‘A’ + ‘B’ Flow
Figure 16a: Multiple Units with Internal Flow Controllers