Harman PF100, Инструкция по установке и эксплуатации

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18
3-90-08101R23_06/13
Adding Air Conditioning to the pellet furnace.
An easy rule of thumb for A/C CFM blower size is, .75 to
1 CFM for each square foot of conditioned space. (std. 8’
ceiling height)
This furnace can be fitted with an air conditioning coil
mounted in the supply air plenum.
HHT is not responsible for sizing, duct placement, or
interconnections. However we have made adding A/C to the
furnace easier with the information listed below.
There is a factory installed junction box ready to accept your
A/C relay. The A/C fan control center with 40 va transformer
must have a DPDT relay. White Rodgers # 90-112, part #
3-20-38056 is available. Other brands are also acceptable
for use.
The wiring should be done as per Fig. 34. The low voltage
wiring to the outside condensing unit and the cooling
thermostat are not shown. See condensing unit diagrams
for that information.
This style of relay is used to lock out the feeder system of the
pellet furnace when the A/C unit is calling for cooling. This
is a fail-safe against both units operating at the same time.
See the NOTE in the lower left corner.
recommendations for Supply Air and return Air duct
sizing.
The speed or velocity of air moving through duct systems
increases as the duct decreases in size with the same CFM
blower. The sound of air flowing through the duct increases
as the velocity increases. Therefore the largest duct size
practial should be used.
The velocity to sound level must be taken into consideration
when connecting this furnace into an existing duct system.
As a primary source furnace the duct system can be installed
to fit the customers needs.
These are recommended Supply Air duct sizes (in square
inches)for some of the different CFM blowers that may be
used with this furnace.
velocity 500fpm 700fpm 900fpm
Static-In. W.C. .3 Minimum to .6 Maximum
1000 cfm. 270 in² 210 in² 160 in²
1450 cfm 360 in² 290 in² 220 in²
1638 cfm 470 in² 360 in² 290 in²
(These duct sizes are only recommendations. )
The Return Air duct system should be sized aproximately 10
percent larger for heating only systems and 20 percent larger
if air conditioning is installed.
Installing duct
NOTE:
It is highly recomended that the furnace
control be turned to the “OFF” position
whenever air conditioning is being used,
whether or not it is interconnected.
CAuTION: Regardless of the supply air duct
size installed, the Distribution Blower Motor
muST be checked for running Amperage.
Check the motor name plate for the full load
AMPS. If the amperage is running higher than
that listed, a supply air restricting damper may
be required to increase the supply plenum
positive static pressure.
Fig.34