Manual

Mammoth V-Cube Slim IOM, MAMM-VCS-IOM-4FA (October 2013) 15
Troubleshooting
Charts in this section provide general guidelines on
troubleshooting problems with your V-Cube Slim unit. If
Service assistance is required contact Mammoth Service
at [phone]. For additional help diagnosing prob-
lems or servicing the unit, contact your local Mammoth
representative. For assistance locating your Mammoth
representative, call 952-358-6600 or e-mail info@mam-
moth-inc.com.
Table 2: Refrigeration system troubleshooting*
Symptom
Head
Pressure
Suction
Pressure
Compressor
Amp Draw
Super Heat Subcooling
Air Temp
Differential
Water Loop Temp
Differential
Safety
Lockout
Undercharged system Low Low Low High Low Low Low Low Pressure
Overcharged system pressure High High High Normal Low Normal Normal High Pressure
Low air flow in cooling Low Low Low Low or Normal Low Low Low Low Temp
Low water flow in cooling High High High High Low Low High High Pressure
High air flow incooling Low High Normal High Low Low Normal High Pressure
High water flow in cooling Low Low Low Low HIgh Normal Low Low Temp
TVX restricted High Low Normal or low High High Low Low
* Referenced values for your unit are recorded on the factory run test sheet. This sheet is part of the unit documents provided with your unit.
They are located within the main electrical panel.
Figure 13: Performance troubleshooting
Problem Heating Cooling Possible Cause Solution
Insufficient Capacity X X Dirty Filter Replace or clean
Not cooling or heating
properly
X X Reduced or no air flow Check for dirty air filter and clean or replace, Check fan motor operation and airflow
restriction. External static too high? Check static vs. blower table
X X Leaky duct work Check supply and return air temperatures at the unit and at distant duct registers: If
significantly different, duct leaks are present
Unit doesn’t operate in
cooling
X X Low refrigerant charge Check superheat and subcooling
X X Restricted metering device Check superheat and subcooling– replace
X Defective reversing valve Perform RV touch test
X X Thermostat improperly located Check location and for air drafts behind stat
X X Unit undersized Recheck loads & sizing. Check sensible, cooling load and heat pump capacity
X X Scaling in waterside heat exchanger Perform scaling check and clean if necessary
X X Inlet water to hot or cold Check load, loop sizing, loop backfill, ground moisture
High head pressure X Reduced or no air flow in heating Check for dirty air filter and clean or replace. Check fan motor operation and airflow
restrictions. External static too high? Check static vs. blower table
X Reduced or no water flow in cooling Check pump operation or valve operation/setting. Check water flow; adjust to proper flow rate
X Inlet water to hot Check load, loop sizing, loop backfill, ground moisture
X Air temperature out of range in
heating
Bring return air temp within design parameters
X Scaling in waterside heat exchanger Perform scaling check and clean if necessary
X X Unit overcharged Check superheat and subcooling
X X Non-condensable in system Vacuum system, reweigh in charge
Low suction pressure X Reduced water flow in heating Check pump operation or valve operation/setting. Check water flow adjust to proper flow rate
X Water temperature out of range Bring water temp within design parameters
X Reduced air flow in cooling Check for dirty air filter and clean or replace. Check fan motor operation and airflow
restrictions. External static too high? Check static vs. blower table
X Air temperature out of range Too much cold vent air? Bring entering air temp within design parameters
X X Insufficient charge Check for refrigerant leaks
Low discharge air
temperature in heating
X Too high of air flow Check fan motor speed selection and airflow
X Poor performance See insufficient capacity