Carrier 58PHA/PHX instruction manual Canada, Follow exclusively the National Fuel Gas Code

The input rating for altitudes above 2,000 ft. (610 M) must be reduced by 4 percent for each 1,000 ft. (305 M) above sea level. For installations below 2000 ft. (610 M), refer to the unit rating plate. For installations above 2000 ft. (610 M), multiply the input on the rating plate by the de-rate multiplier in Table 8 for the correct input rate.

In Canada:

The input rating must be derated by 10 percent for altitudes of 2,000 ft. (610 M) to 4,500 ft. (1372 M) above sea level by an authorized Gas Conversion Station or Dealer. To determine correct input rate for altitude, see example 1 and use 0.90 as derate multiplier factor.

EXAMPLE 1:

88,000 BTUH INPUT FURNACE INSTALLED AT 4300

FT. (1310 M)
Furnace Input	X	Derate	=	Furnace Input
Rate at Sea		Multiplier		Rate at
Level		Factor		Installation
		0.90		Altitude
88,000	X		=	79,200

2.Determine the correct orifice and manifold pressure adjustment. There are two different orifice and manifold

adjustment tables. All models in all positions, except Low NOx models in downflow or horizontal positions, use Table 13 (22,000 Btuh/Burner).

Low NOx models in the downflow or horizontal positions must use Table 14 (21,000 Btuh/Burner). See input listed on rating plate.

a.Obtain average yearly gas heat value (at installed altitude) from local gas supplier.

b.Obtain average yearly gas specific gravity from local gas supplier.

c.Find installation altitude in Table 13 or 14.

d.Find closest natural gas heat value and specific gravity in Table 13 or 14.

e.Follow heat value and specific gravity lines to point of intersection to find orifice size and manifold pressure settings for proper operation.

f.Check and verify burner orifice size in furnace. NEVER ASSUME ORIFICE SIZE. ALWAYS CHECK AND VERIFY.

g.Replace orifice with correct size if required by Table 10, 12, 13, and 14. Use only factory-supplied orifices. See EXAMPLE 2.

58PHA

Caution!! For the following applications, use the minimum vertical vent heights as specified below. For all other applications,

follow exclusively the National Fuel Gas Code.

FURNACE		FURNACE INPUT	MIN. VENT	MIN. VERTICAL VENT
	VENT ORIENTATION		DIAMETER	HEIGHT
ORIENTATION		(BTUH/HR)
			IN (MM)*	FT. (M)**
Downflow	Vent elbow left, then up Fig. 38	132,000	5 (127 )	12 (4)
Horizontal Left	Vent elbow right, then up Fig. 41	132,000	5 (127 )	7 (2)
Horizontal Left	Vent elbow right Fig. 42	132,000	5 (127 )	7 (2)

NOTE: All vent configurations must also meet National Fuel Gas Code venting requirements NFGC *4 in. (102 mm) inside casing or vent guard

**Including 4 in. (102 mm) vent section(s)

Table 10 – Altitude Derate Multiplier for U.S.A.

ALTITUDE		PERCENT	DERATE
(FT. / M)		OF	MULTIPLIER
		DERATE	FACTOR*
0–2000 (0--- 610)		0	1.00
2001–3000 (610	--- 914)	8–12	0.90
3001–4000 (914--- 1219)		12–16	0.86
4001–5000 (1219	--- 1524)	16–20	0.82
5001–6000 (1524	--- 1829)	20–24	0.78
6001–7000 (1829	--- 2134)	24–28	0.74
7001–8000 (2134	--- 2438)	28–32	0.70
8001–9000 (2438	--- 2743)	32–36	0.66
9001–10,000 (2743--- 3048)		36–40	0.62

*Derate multiplier factors are based on midpoint altitude for altitude range.

3.Adjust manifold pressure to obtain correct input rate.

a.Turn gas valve ON/OFF switch to OFF.

b.Remove manifold pressure tap plug from gas valve. (See Fig. 52.)

c.Connect a water column manometer or similar device to manifold pressure tap.

d.Turn gas valve ON/OFF switch to ON.

e.Manually close blower door switch.

f.Set thermostat to call for heat.

g.Remove regulator seal cap and turn regulator adjusting screw counterclockwise (out) to decrease input rate of clockwise (in) to increase input rate.

EXAMPLE 2: (0 to 2000 ft. (0 to 610 M) altitude) For 22,000 Btuh per burner application use Table 13. Heating value = 1000 Btuh/cu ft.

Specific gravity = 0.62 Therefore: Orifice No. 43* Manifold pressure: 3.7-in. wc *Furnace is shipped with No. 43 orifices.

In this example all main burner orifices are the correct size and do not need to be changed to obtain proper input rate.

h.Install regulator seal cap.

i.Leave manometer or similar device connected and proceed to Step 4.

NOTE: DO NOT set manifold pressure less than 3.2-in wc or more than 3.8-in. wc for natural gas at sea level. If manifold pressure is outside this range, change main burner orifices. Refer to Table 10, 12, 13, and 14.

NOTE: If orifice hole appears damaged or it is suspected to have been redrilled, check orifice hole with a numbered drill bit of correct size. Never redrill an orifice. A burr-free and squarely aligned orifice hole is essential for proper flame characteristics.

4. Verify natural gas input rate by clocking meter.

NOTE: Gas valve regulator adjustment cap must be in place for proper input to be clocked.

a.Turn off all other gas appliances and pilots served by the meter.

b.Run furnace for 3 minutes in heating operation.

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