Heat does something pressure cannot, which is the case for XHW hot water pumps. It drops the viscosity of grease and oil so detergent gets underneath, it shortens dwell time because chemistry runs faster warm, it kills bacteria on food-contact surfaces, and it cuts how much detergent you need in the first place.

A cold-water pump run on hot water fails early, usually at the water seals, and the failure looks like a slow loss of pressure rather than a dramatic event. The XHW series is AR’s compact hot-water line. Ratings differ by model, so check the one you are buying: the XHW08.15N is listed for 180°F.

The two brass-head models

Both use a nickel-plated brass head, aluminium connecting rods, stainless plungers, a 32 oz crankcase, and 3/4 in F inlet with 3/8 in F discharge.

The XHW08.15N is the compact one: commercial kitchens, cabinet washers, small workshops, anywhere space is tight and 2 GPM is enough. The XHW11.17N is the one most people end up with, for truck wash bays, food and beverage plants, ag sanitation and industrial equipment cleaning.

Hot water and stainless are two different problems

This trips people up constantly. A 180°F temperature rating tells you the seals and materials survive heat. It says nothing about what happens when the water carries chlorinated sanitizer or salt.

If you need both, the XHW-ASS variants add a stainless head and PTFE seals on an F33 (56C) motor flange:

• XHWASS1G15E-F33, 1.0 GPM at 1,500 PSI
• XHWASS1.8G15E-F33, 1.8 GPM at 1,500 PSI
• XHWASS3G15E-F33, 3.0 GPM at 1,500 PSI
• XHWASS3.5G15E-F33, 3.5 GPM at 1,500 PSI

You trade pressure for chemical resistance, which is usually the right trade in sanitary washdown. Nobody needs 2,500 PSI to rinse a food-contact surface, and plenty of people need the head to survive quaternary sanitizer.

Building a hot water system around one

The pump is rarely the weak point. Check these four things:

• Heater capacity at flow. Your heater has to hold 180°F while delivering 2.1 or 2.9 GPM, not just at idle. Temperature sag under load is the most common disappointment.
• Everything downstream. Pressure ratings fall with temperature. A hose rated 3,000 PSI cold is not rated 3,000 PSI at 180°F. Confirm hose, gun, swivel and fittings at working temperature.
• Bypass to tank, not to inlet. On a hot system, recirculating bypass stacks heat on heat and pushes the pump past its seal rating while the operator stands there with the trigger released.
• Inlet filtration. Hot water plus grit scores valve seats faster than either does alone.

Servicing XHW hot water pumps

The XHW is fully rebuildable: valve set, piston kit, water seals rated for the temperature, oil seals and support rings. Kits are model specific, so confirm the part against your MPN before ordering.

On hot water, shorten the intervals you would use on a cold system. Heat ages seals whether the pump is running or not, and a water seal replaced early costs a fraction of the bearing damage that follows one replaced late. Watch for milky oil, which means water is already getting past.

Where XHW hot water pumps are used

• Food and beverage: floor, equipment and washdown station sanitation under USDA and FDA hygiene programs
• Fleet and transport: degreasing truck bays, removing road salt and diesel residue
• Agriculture: hog barns, dairy parlours, tractors and implements
• Restaurants: kitchen, hood and duct grease removal
• Manufacturing: machinery carrying cutting fluid and process oil

Browse the full hot water pump range, or send your heater capacity and inlet temperature and you will get a model that matches the rest of your system.