Parker Airtek MSC Series, Руководство пользователя

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MSC4000 - MSC15000 USER GUIDE
1.
You need to first check the coil of the liquid line valve to ensure that it is functioning. The
easiest way to verify if the coil is energized is to take a screwdriver or a piece of metal and
touch it to the screw or post on the top metal to the screw or post. If the Power Saver
Active light is off and there is no magnetic pull, the coil is not functioning.
2.
If you have determined the coil is not functioning there are two things you must check.
- Test the coil electrically for continuity to ensure it is not shorted. If it is shorted replace
the coil.
- If the coil is not shorted you need to check the K2 relay marked “Suction”, terminals 7
and 8. There should be an output from this relay. If there is, replace the board.
3. If the coil is functioning and the restriction seems to remain the valve may be the problem.
The internals or the whole valve should be replaced. Or the restriction could be in the
expansion valve. This is rare but possible.
Remember all of this must be checked while the unit is operative and in the refrigerating state.
The way this is determined is by the Power Saver Active light being off.
G) Service Valve Closed
When the dryer is fully operative, all refrigeration service valves with the exception of the
service valve on the bottom of the evaporator Models 300’s and up, should be open. If one
should be closed, even partially, this could cause enough of a restriction to cause high-
pressure problems.
H) Faulty Expansion Valve
This is a very rare situation however there is means of testing this theory. Test by applying
heat (hair dryer) to TXV sensing bulb located just after the flood level control for about 30-45
seconds. This should cause the unit to flood back and lower the super heat. To check this,
take a temperature reading on the suction accumulator, it should be extremely cold, if it is not,
your expansion valve is stuck closed or is dirty.
I) Disconnected or Faulty Jumper Wire (Very rare)
There is an orange jumper wire that runs from the outgoing current on the high-pressure switch
to terminal 19 on the main dew point controller. This terminal must see power at all times in
order for the unit to function. If the high pressure switch opens it severs power to terminal
19 and the unit shuts down on “E7”. However, if the jumper wire is faulty or disconnected
terminal 19 does not see power and will shut down on a false “E7”. To check, remove power
from the unit and check for continuity through the jumper wire if there is none inspect and/
or replace wire. Reapply power. If the unit still shows “E7” and the high-pressure switch has
checked good, the problem is in the board.
9.8 Diagnostic Code “E9” Drain Shutdown
If the drain switch remains closed for 30 minutes, the unit will shut down and flash “E9”. Repair
drain switch problem and reset unit.
11. INSTRUCTION FOR ORDERING REPAIR PARTS
When ordering parts, specify dryer model and serial number. (See nameplate of the unit).
All orders for parts should be placed with your distributor.