PHW – Portable Hot Water

Portable Hot Water Heaters (PHW) for Rail and ISO operate in a greenfield and are environmentally friendly. These trailered heaters can do the duty of steam boilers at less cost.

When a steam coiled tank is cold, most of the time it is moved to a stationary steam boiler. Works great (if you have a steam boiler, a locomotive, a boiler operator, a boiler operator’s license, chemical water treatment, a header, hoses, a few valves, and a return line).

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We have heard of people carrying their tanks many miles for a "steaming".  Now there is an option.  North Star Group has worked out arrangements with one of the best hot pressure washer companies in the country.  Since the mid-1960's Alkota ( has made fine hot-water heaters, hot pressure washers, and more. With Alkota making our skids for North Star Group Portable Hot Water Heaters for Tank Cars and ISO containers, taking good care of customers has never been easier.

With Alkota the price value mix gets "just right".  At $27,900 (skid) we have, we think the best combination of value and price anywhere in the world. A quick look at the two of the specs:

HEATER:   Model 760 Water heater with 115 Volt Burner, 700,000 BTU’s with Exhaust Stack

ENGINE:     9.5 HP (or larger, depending on availability) Kohler Diesel Air Cooled Engine

Steaming is quick, and if you do a lot of cars it is inexpensive and fast on a per car basis.  But and it is a big "but", if you are in the middle of the proverbial wheat field, the portable hot water heater for ISO containers and rail tank cars might be a great alternative. Trailer model is pulled by a pickup truck too.

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A quick note on chilly weather.  We understand freezing weather.  This is why a ceramic heater comes standard as well as a freeze release. When it gets to freezing temperatures, the device automatically opens and drops the pure water that is in the tank and pipes to the ground.

Designed by North Star.  Manufactured in the USA by Alkota. We would say "get them while they are hot", but these heaters are always hot when you want them to be.


Steam coiled Rail Tank Cars and ISO Containers carry the liquids civilization needs by rail, like blood through arteries.  When cold, liquids gel or freeze the liquids are “stuck” in the rail tank car.  In most circumstances, the cars are steamed by injecting through the coils.  Sometimes steam is too hot and damages the contents and other times, steam is not available.

Example: A manufacturer is receiving four truckloads a month of a liquid, plastic or food realizes that switching to one rail tank car a month reduces shipping costs and provides the satisfaction of enough inventory.  Purchasing a boiler and setting up a steam line represents a prohibitive capital expense. PHW solves this problem with ease.

The PHW  provides circulating hot water at up to 200 ⁰F with heater output up to 275 °F.  PHW is available on a skid, in an open trailer or a closed trailer. A trailer mounted system weighs about 13,500 pounds when loaded for operation & it burns 6-7 gallons of diesel per hour at high fire. (It is not designed to need continuous high fire, unless the ambient temperature is very cold.

Hot water flows in and out of the 600-gallon reservoir creating more efficient heat transfer by sparging the reservoir before circulating out.   A direct drive pump takes the water from the tank and sends it coursing through the existing steam lines of a rail tanker providing heat transfer without thermal shock or scorching.

Unlike most boilers, an operator certificate isn’t needed for the PHW. It is a simple, sturdy machine with sub-components put together by top-notch craftsmen and “Made in the USA” that runs with minimal supervision.

Usually, heating tanks is an industrial sized operation with expensive equipment that starts at $100,000 and goes up from there with licenses and operators.  The vessels (tank rail cars, ISO container, truck trailers) are brought to a stationary facility and steam heated at the facility.

Steam process is great for large transloading facilities, but not great for smaller volumes.  An occasional rail tank car does not justify the spend on operators, steam boilers, lines, installation of sports and other capital equipment nor the cost of switching.  The cost of purchasing one hot truckload at a time is greater than the cost of purchasing in bulk and having an ISO container or rail tank car as a portable storage tank.

Sea Containers are popular.  Worldwide, there are more than 500,000 liquid cargo sea containers. Most of them have steam coils.  The same steam coils work for either hot water or steam.  The fleet of rail tank cars carrying bulk liquids is more than 250,000 rail tank cars.  Liquid cargo is about 8% of the overall freight or about $1.5 trillion dollars of liquid cargo is moved each year.


The PHW is easy to use, safe, non-pressurized, source of hot water that brings the heat to the work, instead of the work to the heat.  The cost of a PHW is a fraction of the cost of a typical boiler or hot water setup.  No license required, no special training, inexpensive labor operates the PHW.  This is less expensive than having an operator’s license to operate intrinsically dangerous boilers.

Operators can use one PHW for more than one location.  It is Interstate travel safe.

The PHW is made with high quality parts and lasts a long time.


People that handle ISO containers like the PHW because of the low cost, convenience, reliability, and lack of government regulation.

Our first customer, who has had the PHWs he owns in continuous duty, wants to purchase another PHW and HIG is working to meet his expectations on the purchase quote.  If things are satisfactory, we expect this customer to own his third machine.

With these machines, manufacturers that sell in bulk can compete with the trucking companies because it becomes easier for the end user to handle bulk liquids.  Like anything else, the bigger the quantity purchase, the better the price.  End users that want discounted liquid prices are customers.

Other customers are those that handle ISO tanks and those that transload rail tank cars.  There are thousands of facilities that handle rail tank cars and many of them will see the PHW as a yard tool.  Some transloaders are starting a facility and need the self-contained heat that the PHW offers.  The PHW works by itself and needs no utility hookups.  It runs on simple water and is environmentally safe. Small transloaders that only handle dry goods now will want a PHW to expand their ability to handle liquids too.

Portable Hot Water (PHW) is a tool that allows unused sidings to store liquid, prevents unnecessary locomotive use, and is safe – using plain water in its 240F 30GPM closed system.

Skid Mount Description

North Star Group Inc warrants that your Atmospheric Hot Water heater will be free of defects in materials or workmanship (under normal use) for one year from the date of purchase.

This PHW heater is 700,000 BTUs. It operates on #2 Diesel.


  • Electric Start Diesel Engine (between 8 and 10 HP)
  • Carbon Steel 550 Gallon tank
  • Direct drive, pulley driven 30-40 Gallons per Minute pump
  • Electric 12 Volt Pump at 8-10 Gallons per Minute
  • 1” and 2” Carbon Steel Pipe
  • Ball Valves as needed
  • Skid Mounted
  • Fuel Tank (between 90 and 100 gallons)
  • Vents and stacks as needed
  • Generator Head
  • Marine Battery (12 V)

$27,900 (Hoses, Adders, and Taxes not Included). FOB South Dakota.


Our customers need to heat rail tankers and Frac tanks inexpensively to a flowable temperature.  Bioliquids (Biodiesel, Biomass) consumers, distributors, jobbers, are excellent candidates as are the leasing and rental companies that serve them.  The biodiesel market is about 2 billion gallons.  Another market contains the trans-loading facilities.  There are about 3100 trans-loading facilities.  Many of them do not have hot water.  The third market to address is in soybean oil production.  Soybean oil needs to be at flowable temperatures.  The fourth market is the waste vegetable oil market.  (WVO). Each of these markets can absorb many units. Larger orders can be foreseen from the larger rental companies.  Medium orders from good sized distributors that need to strategically place their rail tankers to supply to the home heating market.  Smaller orders can be sought from the rest of the marketplace. Geographically, we should concentrate on areas where the average ambient temperature is below 40F in the winter. There are over 3100 trans-load facilities in US.  Based on a rough review, one third to one-half of all of the trans-load facilities do not offer hot water and steam heat.

Regular Model In A trailer
Regular Model In A trailer
Super Hot Pressurized Model
Super Hot Pressurized Model
Flow Chart Portable Hot Water
Flow Chart Portable Hot Water
Transload Facilities
Transload Facilities

Variety of Models

Inside Shot
Space Age Version of Portable Hot Water Heater