What Pressure Should R-410A Be?

Updated October 26, 2026

R-410A A1 Lower toxicity, no flame propagation

Goodman and Lennox publish a running pressure for each R-410A unit they list. The ranges here come from those tables, not from a rule of thumb.

Read a gauge high and you can recover refrigerant chasing an overcharge that was never there; read it low and you add refrigerant to a system that was already full. The row for your outdoor temperature, and the unit's own charging label, keep a healthy reading from looking like a fault.

At 95°F outdoors, manufacturer tables list a running R-410A system at 134–155 psig suction (low side) and 329–413 psig liquid (high side), read at the service valves.^[1]^[2]^[3]^[4]^[5]^[6]^[7]^[8]^[9] That spans 63 Goodman and Lennox outdoor units, with Goodman's at 80°F/67°F indoor air.^[1]^[2]^[3]^[4]^[5]^[6]^[7]^[8]^[9] Your unit's own table or charging label is the number to check against.^[8]

R-410A high and low side by outdoor temperature

Suction is read at the suction service valve and liquid at the liquid service valve. Each row spans every manufacturer table for that outdoor temperature.^[1]^[2]^[3]^[4]^[5]^[6]^[7]^[8]^[9]

Operating pressure by outdoor temperature, from manufacturer tables
Outdoor	Low side (suction)	High side (liquid)
65°F 18°C	116–145 psig 800–1,000 kPa	217–279 psig 1,496–1,924 kPa
75°F 24°C	124–147 psig 855–1,014 kPa	250–321 psig 1,724–2,213 kPa
85°F 29°C	130–150 psig 896–1,034 kPa	289–365 psig 1,993–2,517 kPa
95°F 35°C	134–155 psig 924–1,069 kPa	329–413 psig 2,268–2,848 kPa
105°F 41°C	136–161 psig 938–1,110 kPa	371–464 psig 2,558–3,199 kPa
115°F 46°C	139–168 psig 958–1,158 kPa	410–527 psig 2,827–3,634 kPa

Operating pressure by outdoor temperature, from manufacturer tables — Goodman spec sheets and Lennox installation instructions

Goodman spec sheets SS-GSX14 (1/19), SS-GSX16 (3/21) and SS-DSXC18 (11/16, high stage) cover 26 units at 80°F/67°F indoor air and each of the three listed airflows.^[1]^[2]^[3] Lennox manuals for XC13, 14ACX, XC21 and XP16 (second stage), XP17 and 13HPX cover 37 units; they list typical pressures without indoor conditions, within ±10 psig liquid and ±5 psig suction.^[4]^[5]^[6]^[7]^[8]^[9]

Every unit at 95°F (79 tables)

Goodman rows are at 80°F/67°F indoor air and the middle of the three listed airflows.

Maker	Model	Type	Low side (psig)	High side (psig)	Source
Goodman	DSXC180361A*	two-stage, high stage	144	348	SS-DSXC18 p. 7
Goodman	DSXC180481A*	two-stage, high stage	147	360	SS-DSXC18 p. 11
Goodman	DSXC180601A*	two-stage, high stage	140	381	SS-DSXC18 p. 15
Goodman	GSX140181M*	single-stage	153	379	SS-GSX14 p. 6
Goodman	GSX140191**	single-stage	151	364	SS-GSX14 p. 8
Goodman	GSX140241**	single-stage	146	368	SS-GSX14 p. 10
Goodman	GSX140251**	single-stage	147	385	SS-GSX14 p. 12
Goodman	GSX140301**	single-stage	150	380	SS-GSX14 p. 14
Goodman	GSX140311**	single-stage	149	372	SS-GSX14 p. 16
Goodman	GSX140361**	single-stage	147	387	SS-GSX14 p. 18
Goodman	GSX140371**	single-stage	147	387	SS-GSX14 p. 20
Goodman	GSX140421**	single-stage	153	403	SS-GSX14 p. 22
Goodman	GSX140431**	single-stage	153	403	SS-GSX14 p. 24
Goodman	GSX140481**	single-stage	150	392	SS-GSX14 p. 26
Goodman	GSX140601**	single-stage	142	410	SS-GSX14 p. 28
Goodman	GSX16[0/A]181**	single-stage	143	346	SS-GSX16 p. 6
Goodman	GSX16S181**	single-stage	146	334	SS-GSX16 p. 8
Goodman	GSX16[0/A]241**	single-stage	143	352	SS-GSX16 p. 10
Goodman	GSX16S241**	single-stage	145	343	SS-GSX16 p. 12
Goodman	GSX16[0/S]301**	single-stage	146	371	SS-GSX16 p. 14
Goodman	GSX16[0311/A301]**	single-stage	150	368	SS-GSX16 p. 16
Goodman	GSX16[0/S]361**	single-stage	145	381	SS-GSX16 p. 18
Goodman	GSX16[0371/A361]**	single-stage	144	373	SS-GSX16 p. 20
Goodman	GSX16[0/S/A]421**	single-stage	144	382	SS-GSX16 p. 22
Goodman	GSX16[0/S/A]481**	single-stage	146	379	SS-GSX16 p. 24
Goodman	GSX16[0/A]601**	single-stage	140	364	SS-GSX16 p. 26
Lennox	XC13-018	TXV	138	362	XC13 506635-01 p. 26
Lennox	XC13-024	TXV	143	379	XC13 506635-01 p. 26
Lennox	XC13-030	TXV	137	380	XC13 506635-01 p. 26
Lennox	XC13-036	TXV	144	404	XC13 506635-01 p. 26
Lennox	XC13-042	TXV	134	364	XC13 506635-01 p. 26
Lennox	XC13-048	TXV	138	377	XC13 506635-01 p. 26
Lennox	XC13-060	TXV	135	371	XC13 506635-01 p. 26
Lennox	XC13-018	fixed orifice (RFC)	138	359	XC13 506635-01 p. 26
Lennox	XC13-024	fixed orifice (RFC)	142	378	XC13 506635-01 p. 26
Lennox	XC13-030	fixed orifice (RFC)	140	380	XC13 506635-01 p. 26
Lennox	XC13-036	fixed orifice (RFC)	146	396	XC13 506635-01 p. 26
Lennox	XC13-042	fixed orifice (RFC)	136	360	XC13 506635-01 p. 26
Lennox	XC13-048	fixed orifice (RFC)	140	377	XC13 506635-01 p. 26
Lennox	XC13-060	fixed orifice (RFC)	140	377	XC13 506635-01 p. 26
Lennox	14ACX-018	TXV	144	351	14ACX 506645-01 p. 27
Lennox	14ACX-024	TXV	142	351	14ACX 506645-01 p. 27
Lennox	14ACX-030	TXV	142	348	14ACX 506645-01 p. 27
Lennox	14ACX-036	TXV	144	366	14ACX 506645-01 p. 27
Lennox	14ACX-041	TXV	146	343	14ACX 506645-01 p. 27
Lennox	14ACX-042	TXV	146	366	14ACX 506645-01 p. 27
Lennox	14ACX-047	TXV	144	361	14ACX 506645-01 p. 27
Lennox	14ACX-048	TXV	141	369	14ACX 506645-01 p. 27
Lennox	14ACX-059/-060	TXV	140	370	14ACX 506645-01 p. 27
Lennox	14ACX-018	fixed orifice (RFC)	143	351	14ACX 506645-01 p. 27
Lennox	14ACX-024	fixed orifice (RFC)	142	347	14ACX 506645-01 p. 27
Lennox	14ACX-030	fixed orifice (RFC)	142	349	14ACX 506645-01 p. 27
Lennox	14ACX-036	fixed orifice (RFC)	145	366	14ACX 506645-01 p. 27
Lennox	14ACX-041	fixed orifice (RFC)	148	348	14ACX 506645-01 p. 27
Lennox	14ACX-042	fixed orifice (RFC)	149	372	14ACX 506645-01 p. 27
Lennox	14ACX-047	fixed orifice (RFC)	144	357	14ACX 506645-01 p. 27
Lennox	14ACX-048	fixed orifice (RFC)	142	371	14ACX 506645-01 p. 27
Lennox	14ACX-059/-060	fixed orifice (RFC)	141	370	14ACX 506645-01 p. 27
Lennox	XC21-024	two-stage, 2nd stage	151	336	XC21 Corp. 0504-L2 p. 18
Lennox	XC21-036	two-stage, 2nd stage	149	339	XC21 Corp. 0504-L2 p. 18
Lennox	XC21-048	two-stage, 2nd stage	141	336	XC21 Corp. 0504-L2 p. 18
Lennox	XC21-060	two-stage, 2nd stage	139	360	XC21 Corp. 0504-L2 p. 18
Lennox	XP17-024	high stage	150	356	XP17 506586-01 p. 31
Lennox	XP17-030	high stage	146	358	XP17 506586-01 p. 31
Lennox	XP17-036	high stage	144	354	XP17 506586-01 p. 31
Lennox	XP17-042	high stage	147	362	XP17 506586-01 p. 31
Lennox	XP17-048	high stage	144	366	XP17 506586-01 p. 31
Lennox	XP17-060	high stage	140	369	XP17 506586-01 p. 31
Lennox	13HPX-018	single-stage heat pump, cooling	141	363	13HPX 506727-01 p. 27
Lennox	13HPX-024	single-stage heat pump, cooling	144	386	13HPX 506727-01 p. 27
Lennox	13HPX-030	single-stage heat pump, cooling	144	403	13HPX 506727-01 p. 27
Lennox	13HPX-036	single-stage heat pump, cooling	138	399	13HPX 506727-01 p. 27
Lennox	13HPX-042	single-stage heat pump, cooling	141	375	13HPX 506727-01 p. 27
Lennox	13HPX-048	single-stage heat pump, cooling	142	381	13HPX 506727-01 p. 27
Lennox	13HPX-060	single-stage heat pump, cooling	137	388	13HPX 506727-01 p. 27
Lennox	XP16-024	two-stage, 2nd stage	146	369	XP16 506640-01 p. 29
Lennox	XP16-036	two-stage, 2nd stage	142	346	XP16 506640-01 p. 29
Lennox	XP16-048	two-stage, 2nd stage	144	372	XP16 506640-01 p. 29
Lennox	XP16-060	two-stage, 2nd stage	138	367	XP16 506640-01 p. 29

Suction pressure tracks the indoor load

Suction rises with the wet bulb of the air entering the indoor coil. In Goodman's tables at 95°F outdoors and an 80°F indoor dry bulb, raising the entering wet bulb from 59°F to 71°F raised suction 9–30 psig on each unit (median 17) and liquid 7–62 psig (median 22.5).^[1]^[2]^[3]

Suction and liquid pressure by entering indoor wet bulb, at 95°F outdoors and 80°F indoor dry bulb
Indoor wet bulb	Low side (suction)	High side (liquid)
59°F	119–151 psig 820–1,041 kPa	290–410 psig 1,999–2,827 kPa
63°F	127–152 psig 876–1,048 kPa	312–411 psig 2,151–2,834 kPa
67°F	139–155 psig 958–1,069 kPa	329–413 psig 2,268–2,848 kPa
71°F	145–161 psig 1,000–1,110 kPa	344–418 psig 2,372–2,882 kPa

Suction and liquid pressure by entering indoor wet bulb, at 95°F outdoors and 80°F indoor dry bulb — Goodman expanded cooling data

Outdoor temperature moves suction too, far less than it moves the high side. From 65°F to 115°F outdoors, suction rose 7–33 psig across these tables (9–17 psig in Lennox's TXV tables, 19–29 psig in its fixed-orifice tables, 19–33 psig in Goodman's at 80°F/67°F indoor), while liquid pressure rose 185–264 psig.^[1]^[2]^[3]^[4]^[5]^[6]^[7]^[8]^[9]

Two-stage units read higher suction on low stage. At 95°F, all 11 two-stage units in these tables read 1–8 psig more suction on low stage than on high stage, and 9 of the 11 read lower liquid pressure; the low-stage tables span 142–154 psig suction and 323–361 psig liquid.^[3]^[6]^[7]

Airflow moves these readings less. Across the three airflows Goodman lists for each unit, suction changed 3–6 psig and liquid 4–15 psig at 95°F.^[1]^[2]^[3]

What the pressures mean in temperature

A PT chart turns each reading into a saturation temperature. At 95°F outdoors, the 134–155 psig suction range is a 46.6–54.6°F dew point at the suction valve, and the 329–413 psig liquid range is a 102.3–118.8°F bubble point, 7–24°F above the outdoor air.^[16] See the R-410A PT chart.

Standing pressure (system off)

With the system off long enough for pressures to equalize, the gauges read the saturation pressure of the liquid refrigerant at its temperature; for a blend held as liquid in a closed container, Arkema gives the liquid (bubble) pressure as the one that applies.^[17] During the off cycle, refrigerant migrates toward the coldest part of the system, so the reading follows that spot's temperature rather than the outdoor air.^[18] NIST notes that non-condensable gas can be diagnosed from its partial pressure while the system is off.^[19]

Standing pressure with the system off and equalized
Off temperature	Standing (psig / kPa)
65°F 18.3°C	186 psig 1,281 kPa
70°F 21.1°C	202 psig 1,391 kPa
75°F 23.9°C	219 psig 1,508 kPa
80°F 26.7°C	237 psig 1,631 kPa
85°F 29.4°C	255 psig 1,761 kPa
90°F 32.2°C	275 psig 1,899 kPa
95°F 35.0°C	296 psig 2,044 kPa
100°F 37.8°C	319 psig 2,196 kPa
105°F 40.6°C	342 psig 2,357 kPa
110°F 43.3°C	366 psig 2,526 kPa
115°F 46.1°C	392 psig 2,705 kPa

Standing pressure with the system off and equalized — Computed from the CoolProp 7.2.0 pressure–temperature dataset.

Checking the charge with these pressures

Lennox calls these tables a guide for maintenance checks, "not a procedure for charging the system."^[4]^[5]^[8]

Charge is set by subcooling on systems with a TXV or electronic expansion valve and by superheat on fixed-orifice systems (capillary tubes and pistons). California's Title 24 verification procedure splits the two methods this way and accepts the manufacturer's target where one exists.^[21] Work it with the subcooling calculator and the superheat calculator.

Older Lennox literature (XC21, 2009) compared pressures with a table like this first, then confirmed the charge with the approach method.^[6]

R-410A vs R-32 vs R-454B at the same conditions

At 95°F outdoors in manufacturer tables:

Refrigerant	Low side	High side	Basis
R-410A	134–155 psig	329–413 psig	63 Goodman and Lennox units; Goodman at 80°F/67°F indoor^[1]^[2]^[3]^[4]^[5]^[6]^[7]^[8]^[9]
R-32	131–153 psig	348–453 psig	26 Goodman and Amana variable-speed units at 80°F/67°F indoor^[10]^[11]^[12]^[13]^[14]
R-454B	138–142 psig	322–351 psig	2 Lennox EL18KSLV sizes in charge mode^[15]

The R-454B row is one heat pump model in its charge mode, so it isn't a like-for-like comparison. At equal saturation temperatures the refrigerants sit closer: at a 45°F dew point, R-410A is 130 psig, R-32 133 psig and R-454B 118 psig; at a 110°F bubble point, 366, 375 and 346 psig.^[16]

Readings that point to a problem

Faults show up as a pattern across suction, head pressure, superheat and subcooling, compared with the same system running normally.^[19] NIST measured these patterns on a 2.5-ton R-410A heat pump with a TXV in cooling mode, and its report also reproduces Breuker and Braun's chart for a rooftop unit with a fixed orifice.^[19]

Fault	Suction	Head	Superheat	Subcooling
Undercharge, superheat still under 16°F	no change detected	lower	no change detected	lower
Undercharge, superheat above 16°F	lower	lower	higher	lower
Overcharge	no change detected	higher	no change detected	higher
Liquid-line restriction, superheat above 16°F	lower	lower	higher	higher
Low indoor airflow	lower	lower	no change detected	no change detected
Low outdoor airflow, superheat under 16°F	higher	higher	no change detected	lower
Low outdoor airflow, superheat above 16°F	lower	higher	higher	lower
Compressor valve leakage	higher	lower	no change detected	lower

TXV system: each reading against normal operation (NIST SP 1087, Table 5.2)^[19]

NIST split its results at 9°C (16.2°F) of superheat, where the TXV runs out of control range. A liquid-line restriction caused no detectable change below that point. Overcharge, low indoor airflow and compressor leakage never pushed superheat past it at the fault levels tested.^[19]

Fault	Suction	Head	Superheat	Subcooling
Refrigerant leak (undercharge)	lower	lower	higher	lower
Liquid-line restriction	lower	lower	higher	higher
Condenser fault (blocked coil)	higher	higher	lower	lower
Evaporator fault	lower	lower	lower	lower
Compressor valve leakage	higher	lower	lower	lower

Fixed-orifice system: Breuker and Braun's chart for a rooftop air conditioner with a short-tube orifice, as reproduced in NIST SP 1087, Table 5.1(a)^[19]

Neither NIST chart covers an overcharged fixed-orifice system. DOE's flowchart below does.

DOE's order of checks

DOE's Building America diagnostics guide works through the readings in order once the indoor coil's temperature split runs more than 3°F below its target, with separate charts for fixed-orifice and TXV systems.^[20]

Reading	Fixed orifice	TXV
Condensing temperature too far above outdoor air	Non-condensables, fouled condenser coil, overcharge or liquid-line restriction	Same
Evaporator saturation temperature too low	Liquid-line restriction, fouled evaporator coil or low charge	Same, or the TXV is out of adjustment
Low subcooling, low superheat	Expansion device overfeed or fouled evaporator coil	TXV overfeed: unsecured bulb or adjustment
Low subcooling, high superheat	Undercharge	Undercharge, or TXV underfeed: bad power element or adjustment
High subcooling, low superheat	Overcharge	Overcharge, or TXV overfeed
High subcooling, high superheat	Low outdoor temperature	Undercharge, or TXV underfeed

DOE gives its limits as starting points. Its Table 3 lists a maximum condensing-over-ambient of 25°F above 12 SEER, 30°F at 10–12 SEER and 35°F below 10 SEER, and a minimum evaporator saturation temperature of 35°F, 40°F and 45°F alongside indoor wet bulbs of 62–63°F, 64–65°F and 66–67°F.^[20] It adds that non-condensables or a liquid-line restriction also raise subcooling.^[20]

Frequently asked questions

What should R-410A pressures be at 80, 90 and 100°F?

Lennox's tables list R-410A in 5°F steps. At 80°F outdoors they show 127–147 psig suction and 278–331 psig liquid; at 90°F, 133–149 and 321–379 psig; at 100°F, 135–151 and 366–433 psig. Goodman's tables use 10°F steps, so they don't cover these temperatures.^[4]^[5]^[8]^[9]

Is 400 psi on the high side normal for R-410A?

It depends on the outdoor temperature. In manufacturer tables, 400 psig sits inside the liquid range at 95°F (329–413 psig) and 105°F (371–464 psig) and above it at 85°F (289–365 psig).^[1]^[2]^[3]^[4]^[5]^[6]^[7]^[8]^[9] Carrier's R-410A units open their high-pressure switch around 610 psig.^[22]

What is R-410A standing pressure?

With the system off and equalized, it is R-410A's liquid (bubble) saturation pressure at the refrigerant's temperature: about 219 psig at 75°F and 296 psig at 95°F.^[17]^[16]

What should R-410A suction pressure be?

Manufacturer tables list 134–155 psig at 95°F outdoors, 116–145 psig at 65°F and 139–168 psig at 115°F. Indoor humidity moves it: in Goodman's tables, suction rose 9–30 psig between a 59°F and a 71°F entering wet bulb.^[1]^[2]^[3]^[4]^[5]^[6]^[7]^[8]^[9]

How these numbers are calculated

Every operating range on this page comes from manufacturer tables, extracted from the PDFs by script rather than retyped, checked for consistent trends and spot-checked against the page images.

Goodman spec sheets list liquid ("Hi PR") and suction ("Lo PR") pressure at the service valves for each outdoor unit at four indoor dry bulbs (70–85°F), four wet bulbs (59–71°F), three airflows and six outdoor temperatures. We use the 80°F/67°F rows, the indoor conditions of the AHRI 210/240 AFull rating test (95°F outdoors), unless a section says otherwise.^[23]

Lennox manuals list typical liquid and suction pressures by outdoor temperature without stating indoor conditions. Two Lennox manuals repeat another's table (XC14 repeats 14ACX; XP13 repeats 13HPX), so each table counts once. Saturation temperatures and standing pressures come from CoolProp 7.2.0.^[1]^[2]^[3]^[4]^[5]^[6]^[7]^[8]^[9]^[24]^[25]^[16]

Sources

[1]
GSX14 Split System Air Conditioner, up to 15 SEER (spec sheet SS-GSX14). Goodman. 1/19. https://apps.goodmanmfg.com/brochures/files/5c5085ab40be5SS-GSX14.pdf (accessed October 20, 2026). Expanded Cooling Data — R-410A liquid (Hi PR) and suction (Lo PR) pressures at the service valves, by outdoor temperature and indoor condition.
[2]
GSX16 Split System Air Conditioner (spec sheet SS-GSX16). Goodman. 3/21. https://apps.goodmanmfg.com/brochures/files/6062166241d6dSS-GSX16.pdf (accessed October 20, 2026). Expanded Cooling Data — R-410A liquid (Hi PR) and suction (Lo PR) pressures at the service valves, by outdoor temperature and indoor condition.
[3]
DSXC18 Split System Air Conditioner, up to 18 SEER (spec sheet SS-DSXC18). Goodman. 11/16. https://apps.goodmanmfg.com/brochures/files/582b1bf6dd15bSS-DSXC18.pdf (accessed October 20, 2026). Expanded Cooling Data — R-410A liquid (Hi PR) and suction (Lo PR) pressures at the service valves, by outdoor temperature and indoor condition.
[4]
Elite Series XC13 Units installation instructions 506635-01. Lennox. 09/11. https://www.lennox.com/dA/1ac2b167d5/Lennox_XC13_IOM.pdf (accessed October 20, 2026). Table 4. Normal Operating Pressures, PDF p. 26 — R-410A typical liquid and suction/vapor operating pressures by outdoor temperature.
[5]
Merit Series 14ACX Units installation instructions 506645-01. Lennox. 07/11. https://www.lennox.com/dA/8b22f61eb8/Lennox_14ACX_IOM.pdf (accessed October 20, 2026). Table 4. HFC-410A Normal Operating Pressures, PDF p. 27 — R-410A typical liquid and suction/vapor operating pressures by outdoor temperature.
[6]
XC21 Series Units service literature Corp. 0504-L2. Lennox. 07/2009. https://tech.lennoxintl.com/C03e7o14l/VIu12Ch2uV/0504g.pdf (accessed October 20, 2026). Table 10. Normal Operating Pressures, PDF p. 18 — R-410A typical liquid and suction/vapor operating pressures by outdoor temperature.
[7]
Elite Series XP16 Units installation instructions 506640-01. Lennox. 12/10. https://www.lennox.com/lib/legacy-res/pdfs/installation_maintenance/lennox_xp16_iom.pdf (accessed October 20, 2026). Table 7. Normal Operating Pressures, PDF p. 29 — R-410A typical liquid and suction/vapor operating pressures by outdoor temperature.
[8]
XP17 System installation instructions 506586-01. Lennox. 06/11. https://www.lennox.com/lib/legacy-res/pdfs/installation_maintenance/lennox_xp17_iom.pdf (accessed October 20, 2026). Table 10. Normal Operating Pressure, PDF p. 31 — R-410A typical liquid and suction/vapor operating pressures by outdoor temperature.
[9]
Merit Series 13HPX Units installation instructions 506727-01. Lennox. 06/11. https://www.lennox.com/dA/138cce8866/Lennox_13HPX_IOM.pdf (accessed October 20, 2026). Table 4. Normal Operating Pressures, PDF p. 27-28 — R-410A typical liquid and suction/vapor operating pressures by outdoor temperature.
[10]
GXV6S Variable-Speed R-32 Split System Air Conditioner, up to 17.2 SEER2 (spec sheet SS-GXV6S-R32). Goodman. 07/25. https://apps.goodmanmfg.com/brochures/files/68ed3c631108aSS-GXV6S-R32.pdf (accessed October 20, 2026). Expanded Cooling Data — R-32 liquid (Hi PR) and suction (Lo PR) pressures at the service valves, by outdoor temperature and indoor condition.
[11]
GXV9S Variable-Speed R-32 Split System Air Conditioner, up to 19 SEER2 (spec sheet SS-GXV9S-R32). Goodman. 07/25. https://apps.goodmanmfg.com/brochures/files/68ed3d136d70fSS-GXV9S-R32.pdf (accessed October 20, 2026). Expanded Cooling Data — R-32 liquid (Hi PR) and suction (Lo PR) pressures at the service valves, by outdoor temperature and indoor condition.
[12]
AXV9S Variable-Speed R-32 Split System Air Conditioner, up to 19 SEER2 (spec sheet SS-AXV9S-R32). Amana. 07/25. https://apps.goodmanmfg.com/brochures/files/68ee8aca01ff7SS-AXV9S-R32.pdf (accessed October 20, 2026). Expanded Cooling Data — R-32 liquid (Hi PR) and suction (Lo PR) pressures at the service valves, by outdoor temperature and indoor condition.
[13]
AZV9S Variable-Speed R-32 Split System Heat Pump, up to 21.0 SEER2 (spec sheet SS-AZV9S-R32). Amana. 09/25. https://apps.goodmanmfg.com/brochures/files/68ee8c439a303SS-AZV9S-R32.pdf (accessed October 20, 2026). Expanded Cooling Data — R-32 liquid (Hi PR) and suction (Lo PR) pressures at the service valves, by outdoor temperature and indoor condition.
[14]
AZV7S Variable-Speed R-32 Split System Heat Pump, up to 19.0 SEER2 (spec sheet SS-AZV7S-R32). Amana. 07/25. https://apps.goodmanmfg.com/brochures/files/68ee8e7c8878dSS-AZV7S-R32.pdf (accessed October 20, 2026). Expanded Cooling Data — R-32 liquid (Hi PR) and suction (Lo PR) pressures at the service valves, by outdoor temperature and indoor condition.
[15]
Elite Series EL18KSLV Units installation instructions 508700-01. Lennox. 12/2024. https://www.lennox.com/dA/9ab528c680/508700-01.pdf (accessed October 20, 2026). Table 6. Charge Mode Operating Pressures, PDF p. 26 — R-454B charge-mode liquid and vapor pressures by outdoor temperature.
[16]
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