Indirect Water Heaters

Select Product Type

Indirect water heaters can use the power of a boiler or furnace to heat stored domestic water. This streamlined approach saves energy because your existing central heating system now doubles as a water heater. Indirect hot water heaters are an excellent option for those looking to take full advantage of their HVAC systems.

Shop by Tank Size

Shop by Brand

Shop by Tank Size

Shop by Brand

Tools & Articles

Let's Talk Indirect Water Heaters

An Intro to Indirect Water Heaters

How to Pick the Right Water Heater

Different Types of Water Heaters

Filter ▼

Best Selling▼

Best Selling
Price: Low to High
Price: High to Low
Name: A-Z
Name: Z-A
Recommends Only
Closeouts Only
In-stock Only
Next Day Air Only
Availability

Filters

Brand

Weil-McLain (9)

Amtrol (4)

Burnham (10)

Buderus (11)

Triangle Tube (7)

Crown Boiler Co. (10)

WSD (9)

+ Show More

Product Line

Alliance LT (5)

Alliance SL (5)

Aqua Plus (5)

Aqua Pro (4)

BoilerMate (1)

Heat-flo (9)

HydroMax (3)

LT (3)

Maxi-Therm 2 (3)

Mega-Stor (4)

Mega-Stor II (3)

S (1)

Smart (7)

SST (4)

SU (3)

+ Show More

Storage Volume (Gallons)

103 (1)

110.9 (1)

111.3 (1)

113.4 (1)

114 (1)

115 (2)

119 (3)

26 (1)

27 (1)

28 (1)

29.7 (1)

30 (3)

31.7 (1)

35 (1)

36 (1)

37.9 (1)

38 (1)

39.9 (1)

40 (3)

41 (3)

42 (1)

46 (1)

50 (3)

50.6 (1)

51 (1)

52.8 (1)

53 (1)

54.1 (1)

55 (2)

56 (1)

60 (2)

67 (1)

70 (3)

79 (1)

79.3 (1)

80 (8)

81.6 (1)

95 (1)

+ Show More

First Hour Delivery (Gallons)

Sometimes called First Hour Rating, this is the number of gallons of hot water the heater can supply per hour when starting with a fully heated tank. The recovery of the water heater depends on your boiler's BTU and boiler output temperature.

100 - 169 (4)

170 - 239 (22)

240 - 309 (13)

310 - 379 (5)

380 - 449 (5)

450 - 519 (4)

590 - 659 (1)

660 - 729 (1)

730 - 799 (1)

870 - 939 (1)

+ Show More

Continuous Recovery Rate (Gallons)

100 - 159 (7)

160 - 219 (20)

220 - 279 (11)

280 - 339 (5)

340 - 399 (6)

400 - 459 (1)

580 - 639 (2)

700 - 759 (1)

820 - 879 (4)

+ Show More

Product Height (Inches)

24 - 27 (5)

32 - 35 (2)

36 - 39 (8)

40 - 43 (5)

44 - 47 (5)

48 - 51 (2)

52 - 55 (6)

56 - 59 (7)

60 - 63 (9)

64 - 67 (1)

68 - 71 (3)

72 - 75 (6)

76 - 79 (1)

+ Show More

Product Width (Inches)

20 (1)

21 (5)

22 (5)

23 (10)

24 (3)

25 (3)

26 (6)

28 (9)

30 (1)

32 (1)

+ Show More

Product Depth (Inches)

20 - 22 (10)

23 - 25 (8)

26 - 28 (8)

29 - 31 (1)

32 - 34 (1)

35 - 37 (1)

41 - 43 (1)

56 - 58 (1)

+ Show More

Connection Type

NPT (43)

Sweat (3)

Union (10)

Weil-McLain Aqua Plus 45 - 39.9 Gal. - Indirect Water Heater

Model: 633600001

14% Buy This

(12)

$1,125.00

In-Stock

Free Shipping & Lift Gate

*This product qualifies for Free Shipping anywhere in the contiguous US. Accessories may ship separately. Items over 100lbs shipped via semi-truck, be sure to select "Lift Gate" to lower the product to the ground curbside. Remote area surcharges may apply, see our full shipping policy for more details.

2% Check Discount

Save 2% instantly by using our convenient "e-check" option or by simply mailing us a paper check. Yes, your order will be delayed slightly (5 business days). But, if you can wait, the savings are significant.