M3

Question 1

What is the montreal protocol?

Answer 1

Protects the ozone layer by phasing out harmful gases like HCFC’s and CFC’s

Question 2

What is the kyoto protocol?

Answer 2

Treaty designed to reduce emission of greenhouse gases

Question 3

What safety items are carried prior to entering a compartment with fridge gas

Answer 3

Multi gas monitor
EDBA if there is a suspected leak

Question 4

What checks are carried out prior to entering a compartment with fridge gas

Answer 4

Check installed gas monitor
Check high and low level ventilation running

Question 5

What compartments onboard have fixed leak detection monitoring and where are the LCP’s located ?

Answer 5

Fridge Plant Room - Portside fridge flat
ECWP’s - LCP outside relevant compartment
FAMR - LCP portside
CAMR - LCP stbdside
AAMR

Question 6

What are the running checks for the main refrigerant plant?

Answer 6

Oil in compressor
Check condenser sight glass for refrigerant
Moisture indicator
Check for ice build up (evaporator)
Check LCP temperatures and pressures in range.

Question 7

Pre starts checks for Main refrigerant Plant

Answer 7

Power to lcp
Oil in compressor sight glass
Check LP pressure
Check LCP for alarms
Check salt water cooling available
Low level vent

Question 8

Demonstrate how to shut down a refrigerant circuit when requested by the chefs

Answer 8

Inform the SCC
Turn selector switch for relevant fridge to “off”

Question 9

How do you reset a HP or LP trip on a Main Refrigeration Plant Compressor?

Answer 9

Push two green switches in front of compressor on HP/LP pressure switch

Question 10

What are the common causes of a HP trip on a Main refrigeration plant compressor

Answer 10

Condenser blocked
Pen Valve not cooling enough
Main SW Valves closed
Sw strainer blocked

Question 11

What are your actions in the event of an LP trip on a Main refrigeration plant compressor?

Answer 11

Check refrigerant level in condenser sight glass
Check liquid line solonoid isn’t damaged
Check evaporator isnt blocked by ice due to insufficient defrost
Check evaporator fan hasn’t failed
Check TEV isn’t damaged

Question 12

What are your reactions to finding ive build up on a Cold store compressor and how do you remedy this?

Answer 12

This means there is no heat exhange happening in fridge space , checl chefs haven’t blocked airflow to evaporator

Inform SCC and put the fridge in to defrost

Question 13

What are your actions in discovering a fire in a refrigerated compartment, where would you locate yourself, who can enter the compartment?

Answer 13

• Leave compartment LVA - contact HQ1/SCC
• Shut the hatch and restricted access to the compartment

-Can only re-enter compartment on air as refrigerant will leave system as a gas when in contact with oustide air temp

Question 14

Describe the general components for a Refrigeration Plant refrigerant circuit

Answer 14

• Compressor , LP to HP gas, cannot compress liquid.

-Oil sep , gravity operated system then feed oil back to compressor

• Condenser , SW medium to cool refrigerant and change gas to liquid.
• Drier, removed moisture from refrigerant
• Moisture Indicator, ensures drier is effective.
• thermal expansion valve , regulates fridge flow to evaporator for most effective heat transfer, works off phial.
• Evaporator , heat exhanger , removes heat from fridge space.

Question 15

What chilled water Plants do we have?

Answer 15

• 2x NECWP’s (Non-Essential CW System)- FAMR (Duplex A & B) and CAMR (Duplex A & B)

• 4x ECWP’s (Essential CW system) fwd phalanx, aft phalanx , radar , ops room

Question 16

What are pre- starts checks for an Essential Chilled water plant

Answer 16

Power available to control panel

Power available to Chilled and salt water pump motors and compressor

All motor starters in auto

Duty chilled water pump selected

Open the SW Supply Valves

Open mode 1 (Normal) Green tally valves

Close Mode 2 (Plate) Red Tally Valves.

Close Mode 3 (Direct) Blue Tally Valves

Check that there is refrigerant in condenser sight glass

Check that there is an oil level in the oil separator

Question 17

Demonstrate the Start Routine for an Essential Chilled water plant

Answer 17

-Local/Remote to “LOCAL”

-Press plant start

-Observe lead chilled water pump start

-After further 30 seconds, observe lead compressor start

• Carry out running checks
• Check the plant pressures and temperatures
• No excessive noise vibration and heat on motors and pumps
• Ensure slide valve opens to over 95% after 2 min delay ( stays open for 10 mins)

Question 18

Demonstrate the start routine for duplex A on a non essential chilled water plant

Answer 18

• Press “Plant Start” push button
• Observe that duty CW pump starts
• Observe that second CW pump starts after 30second delay
  -Observe that duty SW pump starts after 30second delay
  -Observe that the lead compressor starts after 30second delay
  -Observe that the lead conpressor Slide Valve position increases after a 2 minute delay. It should exceed 95% and remains above 95% for a 10 minute period. ensure that the lag compressor starts.
• Carry out plant running checks

Question 19

Demonstrate the stop routine for an essential chilled Water Plant

Answer 19

-Using a MOD 455 key, turn the maintenance switch to the right

• Press “compressor stop” push button for the running compressor’s
• Observe that “pumping down” is displayed on the compressor pages and that the compressors shut down.
• Turn the maintanance switch to the left
• Press “Plant Stop” push button
• Observe that the CW pumps shut down
• Observe that the SW pumps shuts down

Question 20

What are the running checks for an Essential Chilled water plant?

Answer 20

-Check that there is refrigerant in condenser sight glass

-Check that there is an oil level in the oil separator

-Check the plant pressures and temperatures

-No excessive noise, vibration, and heat on motors and pumps

• Check “normal” (mode 1)

CW OUTLET TEMPERATURE 6.5-7.5
DISCHARGE PRESSURE 8 bar