Having trouble
An error code appears in the remote
controller display.
Why do I get different air flow when
running heat pump heat vs. furnace
heat?
During heat pump heating, my indoor
unit (IDU) pipes are not heating
up. What's going on?
Where should I install TH1?
What happens in the event of a heat
pump failure?
My system is flipping between normal
and emergency mode every few
seconds. What should I do?
The W1/W2 buttons on the control
box are not working? Why not?
There are two 'R' and two 'C'
positions in the 'To Furnace' section
on the terminal block. Which one do I
use?
Specifications are subject to change without notice.
PAA-A18, 24, 30, 36, 42AA1/BA1/CA1
Here is the solution (Unit is operating normally)
The protection devices have operated to protect the air
conditioner.
Do not attempt to repair this equipment by yourself. Turn
off the power switch immediately and consult your dealer.
Be sure to provide the dealer with the model name and
information that appeared in the remote controller display.
Higher air flow is generally required when heating or
cooling with the heat pump vs. furnace. To get that higher
air flow, the system uses the Y signal (or Y1 and Y2) to
control the furnace fan during both heat pump cooling and
heat pump heating, whereas it uses W1/W2 signals during
furnace heating. Check your furnace's installation manual
for instructions on configuring the cooling airflow in order
to change the airflow during heat pump (both cooling and
heating) operations.
The first time a system starts up following a power outage,
the compressor will run at a low speed for approximately
5-10 minutes in order to ensure that oil is returned back to
the outdoor unit. You will see capacity ramp up much more
quickly during subsequent heating cycles. Each time you
flip the breaker off on the heat pump, expect a slow ramp
up on the next cycle.
Place TH1 in an area where it will sense the mixed return
air temperatures. However, do not place TH1:
• near a bypass duct
• close to the furnace
If an optimal location of mixed air cannot be identified,
select a location in the return duct of the largest or
most actively used zone.
If the heat pump loses power or otherwise fails to
heat the home, the system will transition into emergency
mode, using the furnace to maintain minimum indoor
temperatures. Emergency mode is configured to run the
furnace according to the non-adjustable thermostat (NAT),
which will call for heat at or around 60° F.
Contact Mitsubishi Electric Trane HVAC US LLC Customer
Care.
These buttons only work when the system is configured to
operate in Test mode.
You can use either one of the two positions.
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