Trane 2TWA0, 2TWA2 manual Checkout Procedure, Troubleshooting Chart What to Check

Installer’s Guide

CHECKOUT PROCEDURE

After installation has been completed, it is recommended that the entire system be checked against the following list:

1.	Refrigerant Line, Leak checked	[	]
2.	Suction Lines and Fittings properly insulated	[	]
3.	Have all Refrigerant Lines been secured and
	isolated properly?	[	]

4.Have passages through masonry been sealed? If mortar is used, prevent mortar from coming

	into direct contact with copper tubing	[	]
5.	Verify tightness of all electrical connects	[	]
6.	Observe outdoor fan during on cycle for clearance
	and smooth operation	[	]
7.	Indoor coil drain line drains freely. Pour water
	into drain pan	[	]

8.	Supply registers and return grilles open and
	unobstructed	[	]
9.	Return air filter installed	[	]

10.Thermostat thermometer is accurate. Check against a reliable thermometer. Adjust per

	instructions with thermostat	[	]
11.	Is correct speed tap being used?
	(Indoor blower motor)	[	]
12.	Operate complete system in each mode to
	insure safe operation	[	]

TROUBLESHOOTING CHART — WHAT TO CHECK

O

.

REF

*

CONTROL

D

WHAT

HIGH

.

.

DEFROST

LOW

STUCK

REF

AIR

CIR

SOVCHECK

CONTACTOR

LOW

EXCESSIVE

RES

DEFROST

TO

REF

TXV

RES .

START

.

.

.

.

COIL

POWERVOLTAGE

RUN

VOLTAGE

INEFFICIENT

O

I

VALVE

CONTACTOR

.

.

SOV

SYSTEM FAULTS CHECK COMPRESSOR

START

VOLTAGE

.

.

CONTROL

NONCONDENSABLESSTUCK

TRANSFORMER

EVAP

RECIRCULATIONRESTRICTIONS

UNDERCHARGE.

RELAY

THERMOSTATCOMPRESSOROVERCHARGE

SUPERHEAT

DEFECTIVE

CAPACITORCAPACITORCONTACTS

AIRFLOW

SUPPLYWIRING

RELAY

WIRING

FUSE COMP

AIRFLOWLEAKINGLEAKING

MODE

IOL

LOAD

OPEN

DEFDEF

COIL

.

. .

REFRIGERANT CIRCUIT

Head Pressure Too High

C

P

P

S

P

S

S

H

P

P

S

P

S

Head Pressure Too Low

C

S

P

S

S

S

S

S

P

H

S

P

S

S

S

S

P

Suction Pressure Too High

C

S

P

P

S

P

P

H

S

S

P

Suction Pressure Too Low

C

P

S

P

S

S

H

P

S

S

S

S

Liquid Refrig. Floodback (TXV)

C

P

P

H

P

P

Liquid Refrig. Floodback

C

P

S

S

S

P

(Cap. Tube)

H

P

S

S

S

S

I.D. Coil Frosting

C

P

S

S

H

Compressor Runs

C

S

P

S

S

S

P

S

S

S

S

Inadequate or No Cooling/Htg

H

S

P

S

S

P

S

S

S

ELECTRICAL

Compressor & O.D. Fan

C

P

P

S

P

S

P

P

Won’t Start

H

P

P

S

P

S

P

P

Compressor Will Not Start

C

P

S

P

S

S

S

P

But O.D. Fan Runs

H

P

S

P

S

S

S

P

O.D. Fan Won’t Start

C

P

P

S

H

P

P

S

Compressor Hums But Won’t Start

C

P

S

S

S

P

H

P

S

S

S

P

Compressor Cycles on IOL

C

P S P S S S

P S P P S

S S

S

S

H

P S P S S S

P S P P S

S

S P

S

I.D. Blower Won’t Start

C

P

P

S

P

S

S

H

P

P

S

P

S

S

DEFROST

Unit Won’t Initiate

Defrost

C

H

P

P

P

Defrost Terminates on Time

C

H

P

P

Unit Icing Up

C

H

P

S

S

S

P

P

C - Cooling

H - Heating

P - Primary Causes

S - Secondary Causes

* - 3 Phase Only

	Literature Order Number	2TWA2-IN-1A	P.I.
	File Number	SV-UN-S/S-2TWA2-IN-1A 9/02
	Supersedes	2TWA2-IN-1 4/02
	Stocking Location	PI Louisville & Webb/Mason - Houston
Trane
A business of	Trane has a policy of continuous product and product data improvement and it reserves the right to change
American Standard Companies
www.trane.com	design and specifications without notice.