12.5-Ton Rooftop Units: Maximum Capacity Before the Big-Cabinet Jump
A 12.5-ton rooftop unit is nominally 150,000 Btu/h of cooling. On the listings in this Commercial Rooftop Units section it is also the largest size before unit weights jump sharply: the 12.5-ton units here weigh roughly 990 to 1,310 lb, while the 15-ton units on the next page start around 1,700 lb. That makes 12.5 tons a practical ceiling for buildings where roof structure, crane access or curb size is a constraint, and it is the size this page is built around.
This is also the deepest category in the section by product count, mainly because Daikin offers its 12.5-ton R-32 units in both standard and high-static blower versions across three voltages and three gas heat inputs. Rheem and Comfortstar round out the cooling-only and gas/electric choices.
Typical Uses at 12.5 Tons
As a general pattern, not a sizing method, 12.5-ton units tend to serve larger single zones: a big-box retail floor split into several rooftop zones, a gymnasium or multipurpose room, a restaurant with a large dining area, a warehouse office and showroom combined, or an open-plan office floor. Many buildings use several 12.5-ton units rather than one large unit, which spreads the load, adds redundancy and keeps each lift within reach of a smaller crane. Whatever the building, the unit should be sized from a commercial load calculation with the real ventilation rate, not from a square-foot rule.
Standard Blower vs. High Static
The Daikin DSG, DHG, DSC and DHC listings at 12.5 tons come in standard and High Static versions. The High Static models carry a larger blower motor in the listings (for example, 5 HP on the high-static DHC compared with 3.5 HP on the standard version). High static is the right call when the unit feeds a long duct run, an older undersized duct system, added filtration such as higher-MERV filters, or downstream components like VAV boxes or duct heaters that add pressure drop. The standard blower is usually the better fit when the ductwork is short and well sized, since a larger motor working at low static just costs energy.
Before choosing, get a measured or calculated external static pressure for the duct system and check it against the blower tables in the manufacturer's spec sheet. Guessing here is how a 12.5-ton unit ends up moving 10-ton airflow.
Rated Capacity and Efficiency
Listed cooling capacities on this page run from about 138,000 Btu/h on the Daikin high-efficiency DHG and DHC to about 142,000 Btu/h on the Rheem units, with the Daikin standard-efficiency DSG and DSC and the Comfortstar CRT7 at about 140,000 Btu/h. Daikin DFG lists 150,000 Btu/h.
On efficiency, the Daikin DHG and DHC lead at 16 IEER and 12 EER. The Daikin DSG and DSC are listed at 15.2 IEER and 11 EER. The Daikin DFG lists 14.2 IEER. Rheem RGEDYB is listed at 14 IEER and 10 EER, and Rheem RACDYB appears both as a Renaissance Classic unit at 11.0 EER and as a 14.2 IEER model. Comfortstar CRT7 lists 11 EER. Note that the high-efficiency tier carries a slightly lower listed capacity than the standard tier at this size, so confirm that the selected model still covers your load at design conditions.
Gas Heat Inputs
Daikin DSG and DHG gas/electric units are listed at 130,000, 180,000 and 240,000 Btu/h input. Rheem RGEDYB is listed at 150,000 Btu/h input. Daikin DFG gas/electric listings are also present. At 12.5 tons, the cooling airflow is high relative to the low heat input, so check the temperature rise range on the product page against your airflow; a mismatch can lead to cool-feeling supply air in heating or high-limit trips when airflow is restricted.
There is no packaged heat pump listed at 12.5 tons in this category. If the owner wants all-electric heating at this capacity, consider two smaller heat pumps from the 7.5 Ton or 10 Ton Rooftop Units pages, or a cooling-only unit with electric heat accessories, after confirming electrical capacity.
Voltage Options
Every 12.5-ton unit here is three-phase. Daikin offers 208/230V, 460V and 575V across DSG, DHG, DSC, DHC and DFG. Rheem offers 208/230V and 460V on RGEDYB and RACDYB. Comfortstar CRT7 is listed at 208/230V. At this capacity, 460V service makes a noticeable difference in conductor and disconnect size, so if 480V distribution is available it is worth pricing both. The listings show MCA and MOP for each model; use those to design or verify the circuit.
Compressors and Staging
The Daikin 12.5-ton listings show two compressors, giving two steps of capacity. The Rheem listings show two-stage operation, with the RACDYB listing two compressors at this size, and a belt-drive blower on a VFD. Comfortstar lists two compressors. Two steps matter more as size increases: a 12.5-ton unit running at full capacity on a mild day can satisfy the thermostat in minutes and leave humidity behind. If the space has a high latent load, discuss staging, airflow at low stage and any dehumidification options with the engineer.
Refrigerants and Field Practice
Daikin's current units use R-32 and the Rheem and Comfortstar units use R-454B, both A2L refrigerants. Use A2L-rated tools and recovery equipment, follow the manufacturer's installation instructions and the mechanical code in force locally, and keep factory leak detection sensors connected and wired as shown. Daikin DFG units use R-410A; since new R-410A packaged equipment is no longer being manufactured for this application, confirm availability and project acceptance before ordering one.
Curbs, Economizers and Roof Work
For change-outs, confirm whether the existing curb matches the new cabinet. Cross-brand swaps normally need an adapter curb or a new curb, and the extra height from an adapter can affect gas piping, condensate and electrical routing. Economizer and ventilation requirements at this capacity depend on climate zone and the adopted edition of ASHRAE 90.1 or IECC; confirm them early, including any fault detection requirement, and order the economizer made for the cabinet. With weights over 1,000 lb on most units here, plan a crane lift, follow the rigging instructions and lifting points in the manual, and verify roof framing if the new unit is heavier than the old one.
12.5-Ton Models in This Category
| Brand | Series | Type | Voltages Listed | Efficiency (as listed) |
|---|
| Daikin | DHG | Gas/electric, R-32, high efficiency, standard or high static | 208/230V-3, 460V-3, 575V-3 | 16 IEER, 12 EER |
| Daikin | DHC | Cooling only, R-32, high efficiency, standard or high static | 208/230V-3, 460V-3, 575V-3 | 16 IEER, 12 EER |
| Daikin | DSG | Gas/electric, R-32, standard efficiency, standard or high static | 208/230V-3, 460V-3, 575V-3 | 15.2 IEER, 11 EER |
| Daikin | DSC | Cooling only, R-32, standard efficiency, standard or high static | 208/230V-3, 460V-3, 575V-3 | 15.2 IEER, 11 EER |
| Daikin | DFG | Gas/electric, R-410A | 208/230V-3, 460V-3, 575V-3 | 14.2 IEER |
| Rheem | RGEDYB | Gas/electric, R-454B, belt drive VFD | 208/230V-3, 460V-3 | 14 IEER, 10 EER |
| Rheem | RACDYB | Cooling only, R-454B, belt drive VFD | 208/230V-3, 460V-3 | 11.0 EER (Renaissance Classic); 14.2 IEER model also listed |
| Comfortstar | Freedom CRT7 | Cooling only, R-454B | 208/230V-3 | 11 EER |
Ratings are from the product listings. Confirm against the manufacturer's spec sheet or AHRI certificate for the exact model number before submitting.
Frequently Asked Questions
What does High Static mean on the Daikin 12.5-ton units?
It is a version with a larger blower motor that can move rated airflow against higher duct resistance. Choose it when the measured or designed external static pressure exceeds what the standard blower can handle, based on the blower tables in the spec sheet.
Is there a 12.5-ton packaged heat pump?
Not in this category. For all-electric heating at this capacity, consider two smaller heat pumps or a cooling-only unit with electric heat, after confirming electrical capacity.
Should I use one 12.5-ton unit or two smaller units?
Two units add redundancy and zoning and each lift is lighter, but they cost more in curbs, circuits and roof penetrations. One unit is simpler if the space is a single open zone. The load profile and the roof decide it.
How heavy is a 12.5-ton rooftop unit?
Listed weights on this page run from about 990 lb for the Rheem cooling unit to about 1,310 lb for the Daikin DHG gas/electric unit. Check the product page for the exact model and plan rigging accordingly.
Why is the high-efficiency Daikin rated slightly lower in capacity?
At this size the listings show about 138,000 Btu/h for DHG and DHC versus about 140,000 Btu/h for DSG and DSC. Efficiency-focused designs can trade a little capacity; confirm the selected unit still covers the load at design conditions.
Which gas heat inputs are offered at 12.5 tons?
Daikin DSG and DHG are listed at 130,000, 180,000 and 240,000 Btu/h input. Rheem RGEDYB is listed at 150,000 Btu/h.
