Marco FRIIA 1000860 Series, Руководство по обслуживанию

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What is R290?
• Common name for high purity propane (C3H8) suitable for use in the refrigeration and air
conditioning industry.
• Hydrocarbon (HC) refrigerant.
• Proven safe, not an environmental threat – has been used in international markets for
10+ years.
• Already used in coolers, display cases, and chill cabinets.
Why not R134A?
• EPA and UE plans ban on R134A, effective between 2019 and 2022.
• Most beverage cooler manufacturers moving to R290 as the alternative to R134A
refrigerant.
5.3. R290 REFRIGERATING CIRCUIT:
FRIIA Service manual Page 18
5.3.1. Overview:
5.3.2 Servicing R290 Equipment:
R290 Service Overview
• It is propane, so it is flammable. You MUST observe caution and proper safety practices
when servicing R290 refrigeration systems.
• Servicing refers to making repairs to the hermetically sealed system and any part of the
electrical system. The EPA and UE set a limit, 150 grams/ 5.29 ounces, on the amount of
R290 charge for commercial applications.
• Repair on R290 systems must always be done in a well ventilated area.
• Because R290 is highly flammable, a combustible gas leak detector is required when
servicing R290 systems.
Servicing R290 vs. R134A
• Operationally very similar systems.
• Operating pressure of R290 system slightly higher than an equivalent R134A system.
Example:
• At 38°C/100°F, evaporating pressure in an R290 system is approx. 46 psig/4,2 Bar.
• At 38°C/100°F, evaporating pressure in an R134A system is 26.6 psig/2.84 Bar.
• (See pressure chart in upper right column.).
• Refrigerant charge in an R290 system is 40 – 60% less than an equivalent R134A
system.
•
Only Marco technicians or service providers trained on procedures for handling
R290 refrigerant gas can carry out repairs on the chillers charged with R290.