Instruction Manual
 
for ChinaTechco Cold/Freezer rooms only
 
 
TECHCO Refrigeration Solution 
 
Taizhou Chengshun Refrigeration Equipment Co.,Ltd
 
Web site: www.chinatechco.com
 
Add: No.98. Yingchun East Road.Hailing Industrial Zoo.Taizhou City.Jiangsu Province.

 
 
ChinaTechco Cold/Freezer Room Technical Handbook
 
With Monoblock Unit
 

 
Table of Contents
 
 
 
Part I ChinaTechco Monoblock Unit ……………….…………3
 
Part II Installation…………………………………….………4-6
 
Part III Servicing manual…………………………...………7-10
 
Part IV Technical Drawings………………………………11-14
 
 
 
 

 
Part I
 
monoblock unit introduction
 
The monoblock units are composed of a condenser unit, an evaporator and a control panel, together in a single compact pack. This configuration allows the highest simplicity on the hand of installation, turning monoblock the most versatile, handy solution for all kind of cold / freezer room projects. The monoblock refrigeration unit can meet the freezing demand in the hotel, restaurant, hospital, agriculture, biology and chemical industry, the temperature of which can be kept with in0 - 8℃, -15- -25℃：
 
Monoblock units are equipped with:
 
Famous compressor brand: Maneurop, Danfoss, Copeland or Tecumseh. Reliable performance and long life-span with well known brand refrigeration parts. EBM fan motor, Castel Solenoid valve.
 
Danfoss high/ low pressure controller, Danfoss filter direr, Eliwell thermostat.
 
Self-supporting housing of galvanized plate Easily detachable front panels
 
Hermetic compressors with engine thermal insulation
 
Electronic control panel with 52 programmable parameters
 
Condensation by air.
 
 
 
 

 
Part II
 
INSTALLATION
 
NOTE: Installation and maintenance are to be performed only by qualified personnel who are familiar with local codes and regulations, and experienced with this type of equipment. CAUTION: Sharp edges and coil surfaces are a potential injury hazard. Avoid contact with them.
 
 
Installation schematic drawing：
 
1.Monoblock Cooling/freezing Units, Panels, Doors, Service tools, Ice
 

pack and Shelves are packed separately in wooden cartons.
 
wooden cartons corner panel
 
2.Installation normally starts with the back wall panels or corner panel.
 
locks
 
3.Wall panels and floor lock together with cam locks. cold/freezer rooms are erected from inside, so installation in confined areas is simple.
 
Monoblock Units roof
 
4.Monoblock Cooling/freezing Units are lifted into position and locked to wall panels by pop rivets or self-tapping screws.
 
Note: Remove power cable from casing to ensure it is on the outside
 

before setting roof.
 
5.Roof Panels installed last.
 
6.Affix Door handle and emergency release,
 
 
793 silicon joints between panels. Clean panels with cleaner and cloth provided.
 
7.Connect
 
monoblock unit wire.
 
Plug into duty
 
sharing power source
 
and allow to pull
 
down to temperature
 
in line with normal
 
good refrigeration
 
practice.
 
monoblock unit connecting wire 
 
8.Put up the shelves to either two or three walls.
 
9.Place the Ice pack on the shelves with holes.
 

 
Part III
 
Servicing Manual
 

Troubles		Possible Cause		Corrective Action
	1. Power failure		1.	Contact power company
	2.	Disconnect switch open	2.	Close switch and check circuits
	3.	Burned-out compressor motor	3.	Replace
Compressor fails	4.	Control circuit open	4.	Locate cause and repair
	a. Overload protector tripped		a. Check overload
to start(no hum)
	b. Thermostat setting too high		b. Set to lower temperature
	c. Low-pressure control open		c. Reset and check pressures
	d. High-pressure control open		d. Reset and check pressures
	e. Loose wiring		5.	Repair wiring
	1.	Improperly wired	1.Rewire unit
			2.Determine reason and correct
Compressor will	2. Low voltage to unit
			3.Replace compressor motor
not start (hums	3. Burned-out compressor motor
			4.	Replace compressor
and trips	4. Mechanical problems in
			5.Install crankcase heater
overload	compressor
protector)	5. Liquid refrigerant in compressor
	crankcase
			1.	Replace overload protector
			2.	Determine reason and correct
			3.	Determine reason and replace
	1.	Defective overload protector	4.	Open compressor discharge
			service valve. Purge possible
	2.	Low voltage to unit
			overcharge of refrigerant. Provide sufficient
	3.	Defective run capacitor
			condenser cooling air to unit
	4.	High discharge pressure
			6. Properly charge system with
	5.	Suction pressure too low
			refrigerant. Increase load on evaporator.
	6.	Suction pressure too high
Compressor			7.	Reduce air flow over evaporator.
	7.	Compressor too hot
starts and runs,			Purge overcharge of refrigerant.
	8.	Shorted motor winding
but short cycles			Replace compressor valves
	9.	Dirty or iced evaporator
			8. Properly charge system with
	10. Low-pressure control differential
			refrigerant.
	set too close
			9.	Replace compressor
	11. High pressure control differential
			10. Increase air flow over evaporator.
	set too close
			Replace broken belt. Replace
	12. Erratic thermostat
			defective fan motor.
			11. Readjust differential.
			12. Readjust or replace control
			13. Relocate or replace thermostat
	1.	Short of refrigerant	1.	Repair leak and recharge unit

 

Unit operates	2. Thermostat contacts stuck		2.	Clean contacts or replace thermostat.
excessively	closed		3.	Check heaters, load and replace unit
	3.	Excessive load	accordingly; replace
	4.	Evaporator coil iced	insulation
	5.	Restriction in refrigerant system	4.	Defrost unit and check operation
	6.	Dirty condenser	5.	Locate and remove
	7.	Restricted air over evaporator	6.	Clean condenser
	8.	Inefficient compressor	7.	Determine cause and correct
			8.	Check compressor valves and
			repair
			1.	Reroute lines to provide proper pitch
	1.	Traps in hot gas and/or suction	2.	Resize risers or install oil return traps
	lines		3.	Repair leak and recharge
	2.	Refrigerant velocity too low in	4.	Adjust expansion valve; alter
	risers		refrigerant charge on capillary
	3.	Shortage of refrigerant	tube system
Compressor	4.	Liquid refrigerant flooding back to	5.	Add 1 pt of oil for each 10 1b of refrigerant
	compressor		added to the factory charge
loses oil
	5.	Gas-oil ratio low	6.	Clean or replace
	6. Plugged expansion valve or		7.	See items under entry “Compressor starts
	strainer		and runs, but
	7.	Compressor short cycling	short cycles”
	8.	Superheat too high at	8.	Change location of TXV bulb or adjust
	compressor suction		superheat to return wet
			refrigerant to the compressor
	1.	Lack of compressor oil	1.	Add oil to correct level
			2.	Reroute tubing
	2.	Tubing rattle
			3.	Repair mounting
	3.	Mounting loose
			4.	Adjust oil level or refrigerant
	4.	Oil slugging
			charge
Compressor	5. Refrigerant flooding compressor
			5.	Check expansion valve for leak or oversized
noisy	6. Dry or scored shaft seal
			orifice
	7.	Internal parts of compressor
			6.	Check oil level
	broken or worn
			7.	Overhaul compressor
	8.	Compressor drive coupling
			8.	Tighten coupling and check
	loose
			alignment
	1.	Ice or dirt on evaporator	1.	Clean coil or defrost
	2.	Expansion valve stuck or dirty
			2.	Clean or replace expansion valve
	3.	Improper TXV superheat
			3.	Adjust expansion valve
Unit low on	adjustment
			4.	Replace valve
capacity	4. Wrong size expansion valve
			5.	Adjust expansion valve
	5.	Excessive pressure drop in
			6.	Clean or replace strainer.
	evaporator
			7.Subcool liquid or add refrigerant
	6.	Clogged strainer

 

	7.	Liquid flashing in liquid line
	1.	Control setting too high	1.	Adjust control
	2.	Expansion valve too small
			2.	Replace valve
	3.	Evaporator too small
			3.	Replace coil
	4.	Insufficient air circulation
Space			4.	Correct circulation
	5.	Shortage of refrigerant
temperature To			5.	Repair leak and recharge
	6.	Expansion valve plugged
high			6.	Clean or replace
	7.	Inefficient compressor
			7.	Check efficiency
	8.	Restricted or undersized
			8.	Clear restriction or resize lines
	refrigerant Lines
			9.	Clean and defrost evaporator
	9.	Evaporator iced or dirty
Suction line	1.	Superheat setting too low	1.	Adjust superheat setting
	2.	Expansion valve stuck open	2.	Clean or replace valve
frosted or
	3.	Evaporator fan not running	3.	Correct problem
sweating
	4.	Overcharge of refrigerant	4.	Correct charge
Liquid line	1. Restricted drier or strainer		1.	Replace drier or strainer
frosted or	2. Liquid line shut-off valve
			2.	Open valve
sweating	Partially closed
Hot liquid line	1.	Expansion valve open too wide	1.	Adjust expansion valve
	2.	Refrigerant shortage	2.	Repair leak and recharge
Top of condenser	1. Refrigerant shortage		1.	Repair leak and recharge
Coils cool when	2. Refrigerant overcharge		2.	Remove part of charge
unit is operating	3. Inefficient compressor		3.	Check efficiency and correct
Unit in	1. Ice plugging expansion valve		1.	Apply hot wet cloth to expansion valve
			body; an increase in suction pressure indicates
vacuum-frost on	orifice
			moisture; install
expansion valve	2. Expansion valve strainer
			a new drier
only	plugged
			2.	Clean strainer or replace valve
	1.	Overcharge of refrigerant	1.	Purge overcharge
	2.	Air in system
			2.	Purge air
High head	3. Dirty condenser
			3.	Clean condenser
pressure	4. Unit in too hot location
			4.	Relocate unit
	5.	Water-cooled condenser
			5.	Clean or replace condense
	plugged
	1.	Shortage of refrigerant	1.	Repair leak and recharge
	2.	Cold unit location
Low head			2.	Provide warm condenser air
	3.	Inefficient compressor valves
pressure			3.	Replace leaky valves
	4.	Leaky oil return valve in oil
			4.	Repair or replace
	separator
	1.	Evaporator overloaded	1.	See previous entry ″Unit operates
High suction	2.	Expansion valve stuck open	excessively”
	3.	Expansion valve too large	2.	Repair or replace valve
pressure
	4.	Leaking compressor suction valves	3.	Replace valve
	5.	Evaporator too large	4.	Replace suction valves or compressor

 

			5.	Resize evaporator
	1.	Shortage of refrigerant
	2.	Evaporator underloaded	1.Repair leak and recharge
	3.	Liquid line strainer clogged	2.Clean or defrost evaporator
	4. Plugged expansion valve		3.	Clean or replace strainer
Low suction	5.	Last charge on TXV power	4.	Clean or replace valve
	assembly		5.	Replace power assembly
pressure
	6.	Space temperature too low	6.	Adjust or replace thermostat
	7.	Expansion valve too small	7.	Replace valve
	8.	Excessive pressure drop	8.	Check for plugged external equalizer
	through Evaporator		9.	Resize compressor
	9.	Oversized compressor
	1.	Automatic defrost control
	erratic or inoperative
	2.	Automatic defrost control	1.	Replace control
	improperly wired
			2.	Rewire control
Evaporator coil	3. Defective defrost control thermal
			3.	Replace control
iced over	element
			4.	Relocate element
	4.	Improperly installed control
			5.	Replace or adjust control
	thermal element
	5.	Defrost control termination point
	too low
	1.	Defrost control incorrectly
	wired
	2.	Automatic defrost control	1.	Rewire defrost control
Cold room	inoperative		2.	Replace defrost control
remains in	3. Defrost control termination point		3.	Replace or adjust control
defrost cycle	too high		4.	Clean or replace solenoid valve
	4.	Defrost solenoid valve stuck open	5.	Relocate unit or provide heat
	5.	Room temperature too low(below
	55°F or 12.8°C)
	1.	Drain tube plugged	1.	Clean tube
	2.	Drain tube frozen
			2.	Check drain heater element and repair or
	3.	Split drain trough
Water collects in			replace
	4.	Evaporator baffle not properly
bottom of EMC			3.	Replace trough
	installed
cooler			4.	Install baffle properly
	5.	Humidiplate not adjusted properly
			5.	Adjust humidiplate
	6.	Door gasket not sealing
			6.	Adjust door or replace gasket
	properly

 
 
 
 
 
 
 
 

 
Part IV
 
Technical Drawings
 
 
power wire
 
the lamp
 
 
 
 
 
 
monoblock unit
 
 
the door
 
 
 
 
 
 
 
 
 
 
 
 
 
installation schematic drawing
 
The monoblock unit structure：

monoblock unit structure
 

Cooling principle chart:
 
Cooling principle chart

 
 

		Electrical circuit diagram
L — Voltage connection		K2 — Lighting	RJ — Themo relay
N  — Neutral connection		K1 —Control connection
M1	—Compressor	JC — Contactor	DC —ELECTROMAGNETISM
M2	— Condenser motor	QJZ  — Crankcase heater
M3	— Evaporator motor	ZJC — Relay	XR40C—E— Tempreture thermostat