Pentair NT Series installation manual Indoor Venting General Requirements

Section III. Installation 14

INDOOR VENTING — General Requirements

The vent pipe must be the same size or larger. The MiniMax NT heaters are capable of a 360-degree discharge rotation and operate with a positive vent static pressure and with a vent gas temperature less than 400° F. The total length of the horizontal run must not exceed the length that is listed below in the tables.

NOTE

The allowable vent runs for each vent pipe diameter are different and can not be exceeded.

Each 90-degree elbow reduces the maximum horizontal vent run by 8 feet and each 45-degree elbow in the vent run reduces the maximum vent run by 4 feet. See the tables below for the maximum vent lengths using 90-degree and 45-degree elbows.

The MiniMax NT is a “Category III” appliance and is an induced-draft pool and spa heater which uses positive pressure to push flue gases through the vent pipe to the outside. This requires a completely sealed vent system—single wall vent pipe with sealed-seams and joints. Flue gases under positive pressure may escape into the dwelling with any cracks or loose joints in the vent pipe, or improper vent installation. The vent pipe must be of a sealed-seam construction, such as those listed for use with “Category III Appliances”, and for operating temperatures less than 400° F. The use of listed thimbles, roof jacks and/or side vent terminals are required; and the proper clearances to combustible materials must be maintained in accordance with type of vent pipe employed—in the absence of a clearance recommendation by the vent pipe manufacturer, the requirements of the Uniform Mechanical Code should be met. The ventilation air requirements for the MiniMax NT heater can be

4 inch Vent Pipe

Number of		Maximum
Elbows
		Vent Run
90°	45°	(Feet)
1	—	22
1	1	18
1	2	14
2	—	14

found on page 16. It is recommended that vent runs over 18 feet be insulated to reduce condensation related problems and/or the use of a condensate trap in the vent run close to the heater may be necessary in certain installations such as cold climates. The MiniMax NT heater is suitable for through-the- wall venting, see table and dimensions below.

Recommended sources for Side-wall vent hood terminals include: The Field Controls Co. (2308 Airport Road, Kingston, NC 28501, (800)742-8368) and Tjernlund Products Inc. (1601 Ninth Street, White Bear Lake, MN 55110, (800) 255-4208)— consult manufacturer for model information and availability.

CAUTION

Do NOT combine exhaust vent pipes to a common exhaust vent in multiple unit installations. Run separate vent pipes.

					Table 8.
5 inch Vent Pipe			5 inch Vent Pipe
Number of		Maximum	Number of		Maximum
Elbows			Elbows
		Vent Run			Vent Run
90°	45°	(Feet)	90°	45°	(Feet)
0	2	45	2	2	29
1	—	45	2	3	25
1	1	41	2	4	21
1	2	37	3	—	29
1	3	33	3	1	25
2	—	37	3	2	21
2	1	33	4	—	21
					Table 9.

THROUGH WALL VENT KITS FOR HEATERS

Part	Dim. A		Dim. B		Dim. C	Dim. D	Dim. E		Dim. F
Number
471532	4	in. Dia.	6	in. Dia.	8½ in.	6 5/16 in.	12	5/8 in.	10	5/8 in.
471543	5	in. Dia.	8	in. Dia.	8½ in.	8 in.	12	5/8 in.	10	5/8 in.

Table 10.

C F

B AE

D

Figure 5.

P/N 472235 Rev. E 4-15-05