Types of Refrigerated Cases
MULTI DECK DELI
MULTI DECK DAIRY
MDDLI= Multi deck deli where sandwiches are sold, lunch meats, etc.
MDDY= Multi deck dairy where dairy products are displayed for sale. Items such as milk, sour cream, cottage cheese, etc.
SERVICE DELI
SINGLE DECK CASE
SVCDLY= Service deli. This is where you buy many types of lunch meat, cheese and/or sandwiches are made. Service meaning someone waits on you.
SDMT= Single deck meat. These cases are often referred to as bunker or coffin cases, as they only have one rack in them for display. They can be medium/frozen temps.
SERVICE FISH
REACH IN FROZEN FOOD
SVFSH= Service fish, where you buy many different types of seafood.
RIFF/RIIC= Reach in frozen food/Reach in Ice cream. RIFF tends to run -5-0 degrees, as they (FROZEN FOOD), do not have to be as frozen as ice cream. RIIC, ice cream has to have a minimum of -7 degrees to hold it solid.
MULTI DECK DELI
MDDLI= Multi deck deli where sandwiches are sold, lunch meats, etc.
MULTI DECK DAIRY
MDDY= Multi deck dairy where dairy products are displayed for sale. Items such as milk, sour cream, cottage cheese, etc.
SERVICE DELI
SVCDLY= Service deli. This is where you buy many types of lunch meat, cheese and/or sandwiches are made. Service meaning someone waits on you.
SINGLE DECK CASE
SDMT= Single deck meat. These cases are often referred to as bunker or coffin cases, as they only have one rack in them for display. They can be medium/frozen temps.
SERVICE FISH
SVFSH= Service fish, where you buy many different types of seafood.
REACH IN FROZEN FOOD
RIFF/RIIC= Reach in frozen food/Reach in Ice cream. RIFF tends to run -5-0 degrees, as they (FROZEN FOOD), do not have to be as frozen as ice cream. RIIC, ice cream has to have a minimum of -7 degrees to hold it solid.
Common Problems with Cases
PRODUCE WET RACK
PRODUCE WET RACK
Prime example of return air grill being blocked by product thus causing temperature issues on case,very common to be seen on produce wet racks & multi deck meat cases.
Another example of a blocked air return grill on a produce wet rack, thus causing temperature problems.
DIRTY CASE
CLOGGED DRAIN
A dirty case such as what you see here can also cause temperature problems, and be a major source of a “case leaking water” call.
Often times you will get a call of a case leaking water,this is most often what you will find is a case with a drain clogged with debris can also cause case to NOT run at desired setpoint temperature.Before you clear a drain with either nitrogen or C02 , first check the floor drain to make sure it is NOT clogged with debris, because if you clear a tub drain inside the case with copious amounts of water, and you HAD NOT checked the floor drain you run the risk of the water running out onto the sales floor creating a HUGE mess to clean up.
CORRODED / RUSTED COIL
RUSTED OUT 53MM POWERHEAD
This coil was removed and replaced on a sandwich bar, as you can see its had years of being exposed to acidic vegetables like tomatoes, vinegar dressings, pickles and so forth. That stuff will eat up a coil over time, and with the coil in this shape you will have temperature issues due to the fins NOT being able to channel proper airflow or pieces of the coil fins blocking the airflow as well by getting wedged in the way.
Based on the condition of this powerhead, its only a matter of time before you receive a service call for a case/cooler not holding temperature, now with that said if you are EVER replacing a coil and you see this , take the extra ten minutes and replace it, even if you are not having temperature problems, replace it anyways.
FAN BLADE
KLIXONS
What you see here a fan blade on a medium temp case (DELI) notice the dirt on the blade, now dirt on the blade can cut down the efficiency by up to 33% also when you look through the opening take notice if the coil has copious amounts of dust, if it does that can be a problem with the case not achieving the setpoint temperature, at which you will need to wash the entire coil. (NOTE) Anytime you work on a case and you see dust on the fan blade clean it off by using a wet rag or if its really bad remove the blade and take it to a sink (Bakery, meat prep) and wash it off.
What you see here are two klixons on a Hill phoenix case, RIFF/RIIC – one is for defrost termination and the other klixon is for the fans. When the coil warms up in defrost, the FAN klixon will OPEN. When the coil comes out of defrost the klixon will CLOSE, energizing the FANS. If the fan klixon is bad you can unplug the white wire (white loop) that energizes the lights, and use it to energize the fans until you replace the FAN klixon.
Deicing A Frozen Case
BOTTOM KICK RAIL OF A RIFF CASE
P-TRAP & DRAIN LINE (HILL PHOENIX CASE)
When you very first come upon a case that has solid, thick ice in the tub, first establish where the drain is located by removing the kick rail.
Once you find the drain, then you will have a visual as to how far inside the case the drain is.
NOTE: The reason for the P-TRAP is keep warm air from traveling through the drain line, thus condensing and causing either the tub or the coil to ice up, it is OKAY to have residual water in the P-TRAP it (WATER) acts as the barrier to warm air intrusion.
FROZEN TUB (RIFF)
CASE DRAIN
Iced up case,now from here you have already identified where the drain line is.
So now get the immediate area around the drain cleared and now you can start fully deicing the case because a water drain path has been established.
CASE DRAIN WITH STRAINER
CASE THROUGHLY DEICED
Notice the debri around this mesh strainer, this is the #1 cause of ALL plugged drains, it is a good ideal to have a trash can nearby to remove all the debris when deicing, not all cases will be clean, some cases will have garbage like peas,corn,hash browns and so forth, do not allow the aforesaid mentioned to go down the drain as you run the risk of clogging it up, keep the strainer in place to catch all debris and remove as need. NOTE:
Make sure the floor drain is clear and free flowing before deicing, or you can have a bigger problem with the water from the tub drain line running all over the sales floor.
Throughly deiced tub in a RIFF case. Be sure to remove ALL the ice,now sometimes it not as easy as this one pictured, sometimes you will have to remove the fan plenum to deice the coil itsel. NOTE: When deicing a COIL it is advisable to have a mirror and flashlight to check BEHIND the coil to properly 100% deice the coil.
CHECKING AMP DRAW OF HEATER
After the case has been deiced throughly, let the water drip for approximately ten minutes or so, turn on the refrigeration to let the coil get cold and energize the fans via the KLIXON closing, let in run in refrigeration mode say 15-20 minutes, then put system into a defrost. The reason for doing this step is to get the fan/termination KLIXON to close because the KLIXON will be warm after deicing with hot water and may not allow the defrost to kick in, so once the coil is below approximately 20 degrees and blowing cold air then put system into a defrost and check your amp draw on the heaters (ELECTRIC DEFROST) if the amp draw is good then use a thermocouple to check and see what temperature the KLIXON terminates. Other things to check:
1) Defrost schedule/times
2)Termination temp
3) Make sure heater is securely mounted to coil. Front & Back heaters
4) Make sure heater is STRAIGHT not wavy or . MUST be straight, mounted in the center of the coil and secured tightly against the coil.
PRODUCE WET RACK
Prime example of return air grill being blocked by product thus causing temperature issues on case,very common to be seen on produce wet racks & multi deck meat cases.
PRODUCE WET RACK
Another example of a blocked air return grill on a produce wet rack, thus causing temperature problems.
DIRTY CASE
A dirty case such as what you see here can also cause temperature problems, and be a major source of a “case leaking water” call.
CLOGGED DRAIN
Often times you will get a call of a case leaking water,this is most often what you will find is a case with a drain clogged with debris can also cause case to NOT run at desired setpoint temperature.Before you clear a drain with either nitrogen or C02 , first check the floor drain to make sure it is NOT clogged with debris, because if you clear a tub in a case with copious amounts of water, and then you HAD NOT checked the floor drain you run the risk of the water running out onto the sales floor creating a HUGE mess to clean up.
CORRODED / RUSTED COIL
This coil was removed and replaced on a sandwich bar, as you can see its had years of being exposed to acidic vegetables like tomatoes, vinegar dressings, pickles and so forth. That stuff will eat up a coil over time, and with the coil in this shape you will have temperature issues due to the fins NOT being able to channel proper airflow or pieces of the coil fins blocking the airflow as well by getting wedged in the way.
RUSTED OUT 53MM POWERHEAD
Based on the condition of this powerhead, its only a matter of time before you receive a service call for a case/cooler not holding temperature, now with that said if you are EVER replacing a coil and you see this , take the extra ten minutes and replace it, even if you are not having temperature problems, replace it anyways.
Additional Information about Cases
TROUBLESHOOTING CASES
This is one of the most important sections. When you first arrive at the service call always check the case in question. If it is a whole lineup i.e., meat, ice cream, produce, etc. that is having problems, then chances are your issue is in the motor room. If it is a single case issue, it is highly probable your issue is with the case itself.
Let’s start with some basics:
First check the airflow. If there is no airflow, then check to make sure the fans are in proper working order. If not then replace them. Sometimes the fan blades will get caked with dirt and dust causing diminished airflow.Also check the honeycomb air diffusers as well,they tend to get plugged solid,if they are then remove them wash & rinse them thoroughly. In that situation you need to clean the the fan blades.
Another thing to check is if the TXV is feeding. If not check, at this time hook up your gauges to suction & liquid and then check superheat. To check this you can pour hot water on the sensing bulb, the preceeding step is for if you suspect the TXV is not feeding properly, If the power head does not feed, then replace it. Another issue that can happen to cause a case to not make proper temperature
is coil can be frozen. If the coil is frozen the first thing to do is de-ice the coil, then check the defrost. While in defrost, check the amp draw at the contactor. If you have an amp draw at the contactor then go down to the case in question. Check the heaters to make sure there is an amp draw. If there is no amp draw then use your ohm meter to check the ohmic value, and look at the heater ends as well. Sometimes they tend to blow up. If the heater checks out then check the heater relay if it is a Hussmann. If its a Hill-Phoenix case then check the Klixon, same with old Tyler cases.
Here are some bullet points to check on a case that is NOT making temperature:
- Fans running?
- Proper RPM motor installed?
- Coil iced up?
- Fan blades clean?
- Heater/heaters working?
- Fan relay energizing/DEenergizing?
- EPR bleeding by in defrost?
- LLS bleeding by in defrost?
- If on a time clock, is the time clock working properly?
- Does the case have proper amount of time, length and number of times of day defrost?
- Do the fans shut off during defrost?
- Are the honeycombs clean?
- Is the case filthy?
- Coil clean?
- Drain inside case clear?
- Do you have proper suction pressure based on what refrigerant is being used?
- Is the TXV screen clear?
- If there is a drier in the case on the liquid line is it free flowing or plugged?
- Do you have a solid sight glass at the rack?
- What is your SST? (Coil Temp)
- Gauges hooked up to suction line at CASE?
- What is the SUPERHEAT?
Last but not least ALWAYS put your gauges on the case in question. If there are NO schrader ports then check your pressures at the rack itself.
TECH TIP: If the case in question has a schrader port on the LIQUID line inside the case remove the cap and slightly depress the schrader. If only vapor comes out then the case is starving for liquid. To confirm this check if drier is plugged before the schrader port. If liquid is PRESENT, then go through the above check list to find the issue.
Follow these steps on your journey to becoming a Journeyman!