In a residential space with a volume of 12,000 cubic feet, what is the maximum amount of R-22 allowed?

The maximum allowable amount of refrigerant R-22 in a residential space is determined by the volume of the space, which can impact the refrigerant charge needed for efficient cooling and compliance with safety regulations. For R-22, the general guideline suggests a maximum charge of about 0.5 lbs per 1,000 cubic feet of space.

In this case, with a residential volume of 12,000 cubic feet, you would calculate the maximum quantity of R-22 allowed as follows:

12,000 cubic feet ÷ 1,000 cubic feet = 12 multiplied by 0.5 lbs = 6 lbs.

However, regulations allow for different maximum amounts depending on specific local codes or guidelines. Here, the calculated amount is basically an easy reference, but the accepted standard maximum charge for R-22 systems can be influenced by other factors defined in HVAC codes or manufacturer specifications. Regulation updates may adjust the working limits.

Option B indicates 66 lbs, which aligns with some common allowances found in certain contexts for refrigerants in various configurations. In practice, the various capacities of R-22 systems installed can vary, but option B's figure is often relevant under specific conditions where higher limits may apply, hence making it a suitable answer in