HOT WATER GENERATOR

 

We offer all available sizes of ASME rated U-Tube Heat Exchangers (“Bundles”) in our Hot Water Storage Tanks.  Given the required amount and temperature of hot water required, we can calculate the size of bundle needed and in most cases install it in the tank before shipment. The standard construction is carbon steel with .75″ copper tubes, but options such as stainless steel or cupro nickel components can be added as required.

Tube bundles can be single or double walled, dictated by the use of the building and local regulations and are installed into a collar that is welded into the tank during production. We normally upgrade to a stainless steel collar in glass and cement lined tanks. This ensures that there are no quality issues with the tank lining inside the collar.

Heater bundles can be installed in both horizontal and vertical tanks and are sized for the most economical dimensions and price that meet the hot water demand.

We also install customer supplied single wall heater bundles and/or unassambled flange/collars that have ASME certs.

In most cases we prefer to furnish the collar and usually stock flanges up to 14″ diameter. Bundles for installation must be received complete with head, nuts, bolts and gasket. Please inquire about larger sizes, which will include extra costs related to blankoffs for pressure testing and shipping as necessary.

We do not install double wall bundles as they are likely to be damaged during shipment.

Longer bundles often need a support. When required, we install one in the most effective location.

A typical temperature rise in a hot water generator is 40 to 140 but this can vary according to local conditions and requirements. The most common heating media in the bundle tubes are 180 pumped boiler water or 15 psi steam. Once again, these are different in many cases and are dictated by the original system design.

Some heat exchangers in cogeneration applications use waste or surplus heat to pre-heat domestic water or even power underfloor heating.

The size and cost of a bundle is less if the water is circulated or agitated. We usually include a recirculation connection in the heater collar to achieve the most efficient bundle performance and to avoid local “hot spots”. Stagnant tanks are not as effective and need a larger bundle to compensate for this. We can calculate sizes required in both cases for a cost comparison to be made.

We install bundles manufactured only by major manufacturers such as Armstrong and ITT Bell & Gossett with whom we have OEM status. This guarantees that the Heat Exchangers we supply are of the highest quality at the best prices. Although deliveries are very prompt at 3-4 weeks, expedited delivery is available if required.

To size a bundle correctly, the following information is needed:

  • The amount of hot water required (“demand”) in gallons per hour.
  • The incoming (cold) water temperature.
  • The outgoing (hot) water temperature.(The difference between 2) & 3) is known as the “Delta T”)
  • The heating medium supplied in the heat exchanger tubes- Steam or Water.
    • If Steam, its pressure after the regulator.
    • If pumped Boiler Water, its temperature and GPM if available.
  • If a single or double wall bundle is required.
  • Whether the tank is agitated or not.
  • Tank size and orientation.

All this information is necessary for the most cost effective bundle sizing. The minimum amount of Boiler Water needed will be stated.

 

TERMINOLOGY
Agitated: See Circulated.
Bonnet: The cap on the outer end of the bundle.
Bundle. The heat exchanger unit. Aka Tube Bundle.
Circulated: Hot water is pumped through the tank constantly.
Cogeneration: Utilizing heat that is a byproduct of another system.
Coil: The heat exchanger unit.
Collar: A short pipe that is welded into the tank and houses the bundle.
Delta-T: The required increase in temperature from cold to hot water.
Double wall: Tube and tube sheet design that prevents boiler water from contaminating

the hot water supply in the event of tube leakage.

Flange: The part welded to the outer end of the collar that the bundle is bolted to.
Fouling factor: An allowance that increases the size of the bundle to ensure that demand

is met even if the tubes become coated with residues from the water.

Recirculation: Hot water is pumped throughout the building constantly. If so the tank is defined as circulated or agitated.
Pass: The number of times the heating medium travels the length of the coil. Two pass is standard. Four or six pass is sometimes necessary.
Tube Sheet: A circular plate that has the open ends of the tubes installed into it.
Tube support: A bracket installed in the tank during production to support the bundle.
U-Tube: The shape of the bundle. The letter “U” laid on its side.

Due to wide variety of options available, we manufacture all units to meet customers’ exact requirements. Here are some examples:

VERTICAL HOT WATER GENERATORS

SIZE
Dia x Lgth
GALLS PRESSURE
psig
WT# SQ.FT DRAWING / PART# COLLAR SIZE LINING INQUIRE PRICE
30″ x 62″ 170 150 427 44 WN-098-B 6″ GLASS GET QUOTE
36″ x 68″ 260 150 545 58 WN-099-B 6″ GLASS GET QUOTE
36″ x 72″ 285 125 602 62 WN-147-B 6″ EPOXY GET QUOTE
36″ x 84″ 348 150 707 71 WK-751-B 14″ EPOXY GET QUOTE
36″ x 94″ 381 125 812 78 WK-699-B 10″ EPOXY GET QUOTE
48″ x 73″ 500 125 1190 85 WM-931-B 6″& 8″ GLASS GET QUOTE
42″ x 96″ 534 150 1020 94 WK-784-B 10″ GLASS GET QUOTE
42″ x 96″ 534 160 1145 94 WN-191-B 6″ GLASS GET QUOTE
42″ x 110″ 600 125 1275 108 WN-373-B 10″ GLASS GET QUOTE
48″ x 112″ 800 125 2087 127 WN-423-B 8″ CEMENT GET QUOTE
54″ x 90″ 803 125 1817 117 WI-495-B 12″ EPOXY GET QUOTE
48″ x 138″ 1000 125 1980 154 WN-077-B 12″ EPOXY GET QUOTE
54″ x 115″ 1040 125 1786 146 WM-891-B 8″ GLASS GET QUOTE
54″ x 135″ 1225 125 2096 171 WN-048-B 10″ GLASS GET QUOTE

HORIZONTAL HOT WATER GENERATORS

SIZE
Dia x Lgth
GALLS PRESSURE
psig
WT# SQ.FT DRAWING / PART# COLLAR SIZE LINING INQUIRE PRICE
24″ x 72″ 130 125 445 40 WM-996-B 4″ GLASS GET QUOTE
30″ x 72″ 200 125 338 51 WM-839-B 6″ GALVINIZED GET QUOTE
36″ x 98″ 400 125 1379 80 WK-760-B 8″ CEMENT GET QUOTE
48″ x 73″ 500 125 1812 86 WM-802-B 10″ CEMENT GET QUOTE
48″ x 106″ 750 125 1460 120 WM-966-B 8″ EPOXY GET QUOTE
48″ x 106″ 754 150 1676 121 WN-440-B 8″ GLASS GET QUOTE
60″ x 130″ 1400 125 3440 184 WK-820-B 12″ CEMENT GET QUOTE
60″ x 128″ 1450 125 3111 183 WN-158-B 8″ CEMENT GET QUOTE
72″ x 144″ 2285 125 5500 246 WI-558-B 10″ CEMENT GET QUOTE