MAXI-FLO Brochure

Boiler
Boiler
Return
Filter
Pump
Return
Skimmer
Boiler
Circulator
To Pool
Balancing
Valve
The size you need,
the performance
you demand
Weil-McLain model WMPH pool heaters
are available in five sizes from 95 to 400
MBH output. Designed for use with Weil-
McLain boilers, these heat exchangers
provide dependable, economical heating
for all types and sizes of swimming pools,
spas and hot tubs.
Key Benefits:

Made of high quality, corrosion-resistant 316 stainless steel, roll-formed and
precision-welded

Specially designed built-in flow restrictor assures maximum heat transfer

Compact size, lightweight with low pressure drop

All units are leak tested to ensure the highest quality

Furnished with stainless steel holding brackets
Better value and support
Backed by Weil-McLain for the best value in
product quality, service and technical support.
Heat Exchanger Selection: A 4-step process
STEP 1:
Determine the desired heat-up rate based on pool usage.

The heat-up rate for extended use (summer season) is 1°F/hr. The heat-up rate for
periodic use (weekends and holidays) is 2°F/hr.
STEP 2:
Determine pool capacity.

Rectangular Pool Capacity = 7.5 x Length (ft) x Width (ft) x Average Depth (ft).

Circular Pool Capacity = 5.9 x Diameter
2
(ft) x Average Depth (ft).
STEP 3:
Select heat exchanger required.

Using the table below, determine the recommended heat exchanger based on your
pool capacity and desired heat up rate.
STEP 4:
Check heat loss to surroundings.

Heat Loss = 12 x (pool surface area in sq. ft) x (desired pool temp) – (coldest average air
temp during use).

Boiler output selected in Step 3 must be more than the heat loss to surroundings.
1°F/hr. Heat-Up Rate 2°/hr. Heat-Up Rate
Pool Capacity Boiler Output Heat Exchanger Boiler Output Heat Exchanger
(gal.) Required (BTU/hr) Model Required (BTU/hr) Model
2,000 17,000 WMPH-95 33,000 WMPH-95
4,000 33,000 WMPH-95 67,000 WMPH-95
6,000 50,000 WMPH-95 100,000 WMPH-135
8,000 67,000 WMPH-95 133,000 WMPH-135
10,000 83,000 WMPH-135 167,000 WMPH-200
12,000 100,000 WMPH-135 200,000 WMPH-260
14,000 117,000 WMPH-135 234,000 WMPH-260
16,000 133,000 WMPH-135 267,000 WMPH-400
18,000 150,000 WMPH-200 300,000 WMPH-400
20,000 167,000 WMPH-200 334,000 WMPH-400
22,000 184,000 WMPH-200 367,000 WMPH-400
24,000 200,000 WMPH-260 400,000 WMPH-400
26,000 217,000 WMPH-260 434,000 WMPH-260 (2)*
28,000 234,000 WMPH-260 467,000 WMPH-260 (2)*
30,000 250,000 WMPH-260 500,000 WMPH-260 (2)*
32,000 267,000 WMPH-400 534,000 WMPH-400 (2)*
34,000 284,000 WMPH-400 567,000 WMPH-400 (2)*
36,000 300,000 WMPH-400 600,000 WMPH-400 (2)*
38,000 317,000 WMPH-400 634,000 WMPH-400 (2)*
40,000 334,000 WMPH-400 667,000 WMPH-400 (2)*
42,000 350,000 WMPH-400 700,000 WMPH-400 (2)*
44,000 367,000 WMPH-400 734,000 WMPH-400 (2)*
46,000 384,000 WMPH-400 767,000 WMPH-400 (2)*
*Two heat exchangers piped reverse return.
Note:
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The typical desired pool temperature is 80°F.
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Heat-up rates will decrease as outdoor temperature drops.
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Use WMPH - 95 for spas and hot tubs with 150 gallons or less capacity.