| They provide backup | 19 |
| Subs ... or a feature of the answers to the 17 asterisked clues? | 64 |
| Star relievers? | 15 |
| Squad of substitutes | 20 |
| Second-string players | 21 |
| Scrubs, often | 13 |
| Practice squad | 14 |
| Non-varsity squad | 17 |
| Blowout substitute? | 19 |
| Bingo call | 10 |
| Vitamin __: PABA | 16 |
| One of a vitamin complex | 24 |
| First-column bingo number | 25 |
| Old bomber | 10 |
| Bingo card number | 17 |
| 1930s bomber | 12 |
| '30s Army bomber | 20 |
| Vitamin also known as PABA | 26 |
| Vitamin a.k.a. para-aminobenzoic acid | 37 |
| Vitamin ___ (PABA) | 18 |
| Square in the first column of bingo | 35 |
| Revolutionary 1930s bomber | 26 |
| Old Martin bomber | 17 |
| Old Army bomber plane | 21 |
| First column bingo call | 23 |
| Early all-metal bomber | 22 |
| Classic Army bomber plane | 25 |
| Certain vitamin | 15 |
| Call that may elicit a "Bingo!" | 41 |
| Call in bingo | 13 |
| Bingo hall call | 15 |
| Bingo call, perhaps | 19 |
| Bingo call or an old bomber | 27 |
| Bingo call in the first column | 30 |
| '30s bomber | 15 |
| AC measure | 10 |
| Heat meas. | 10 |
| Heat unit | 9 |
| A/C unit | 8 |
| A/C meas. | 9 |
| A/C measure | 11 |
| HVAC measure | 12 |
| Air conditioner meas. | 21 |
| Heat measure | 12 |
| Air conditioner capacity, for short | 35 |
| A/C stat | 8 |
| Quantity of heat: Abbr. | 23 |
| Heat measure: Abbr. | 19 |
| A/C capacity measurement | 24 |
| A.C. measure | 12 |
| Energy meas. | 12 |
| Air-conditioner unit: Abbr. | 27 |
| Air-conditioner meas. | 21 |
| Air conditioner measure: Abbr. | 30 |
| AC amt. | 7 |
| Abt. 252 calories | 17 |
| A/C measurement | 15 |
| A.C. unit | 9 |
| Unit of heat, for short | 23 |
| Measure of heat energy | 22 |
| HVAC abbr. | 10 |
| Heat unit: Abbr. | 16 |
| Heat unit, for short | 20 |
| Furnace measure, for short | 26 |
| Calorie alternative: Abbr. | 26 |
| Appliance meas. | 15 |
| AC measurement | 14 |
| AC capacity measurement | 23 |
| A/C capacity meas. | 18 |
| A.C. stat | 9 |
| A.C. letters | 12 |
| 252 calories | 12 |
| Unit of heat: Abbr. | 19 |
| Thermal unit: Abbr. | 19 |
| Therm fraction | 14 |
| Temperature standard: Abbr. | 27 |
| Quant. of heat | 14 |
| Qty. of heat | 12 |
| Plumbing and heating acronym | 28 |
| Measure of heat: Abbr. | 22 |
| Meas. used in heaters | 21 |
| Kilocalorie quarter, roughly (abbr.) | 36 |
| Horsepower fraction | 19 |
| Heating abbr. | 13 |
| Heat unit, briefly | 18 |
| Heat unit (abbr.) | 17 |
| Heat standard Abbr. | 19 |
| Heat quantity: Abbr. | 20 |
| Heat quantity meas. | 19 |
| Heat meas. | 11 |
| English heat measure: Abbr. | 27 |
| Engineering unit | 16 |
| Energy unit: Abbr. | 18 |
| Energy meas. for cooling systems | 32 |
| Cooler's measurement | 24 |
| Central heating measurement | 27 |
| Calorie's big bro. | 22 |
| Bit of heat: Abbr. | 18 |
| BBQ heat rating | 15 |
| Approx. amount of heat given off by burning a wooden match | 58 |