Abstract: A warewash machine for washing wares includes a chamber for receiving wares, the chamber having at least one wash zone. A waste heat recovery unit is arranged to transfer heat from exhaust air of the machine to incoming water traveling along a water flow path through the waste heat recovery unit to a booster heater of the machine. A refrigerant medium circuit includes at least a first condenser arranged to deliver refrigerant medium heat to the incoming water. A control arrangement monitors subcooled refrigerant medium condition and responsively modifies operation of one or more of: (i) speed of a compressor of the refrigerant medium circuit, (ii) speed of an exhaust fan that causes air flow across the waste heat recovery unit or (iii) speed of a pump that controls incoming water flow along the water flow path.

Abstract: A warewash machine includes a chamber for receiving wares, the chamber having at least one wash zone. A refrigerant medium circuit includes a first heat exchanger arranged to deliver refrigerant medium heat to a first fluid and a second heat exchanger arranged to provide a heat exchange relationship between the refrigerant medium and a second fluid, the first heat exchanger located upstream of the second heat exchanger in the refrigerant medium circuit. A bypass arrangement for causing at least some refrigerant medium to selectively bypass at least one of the first condenser or the second condenser based upon subcooled refrigerant medium condition.

Abstract: A flow through chemical sensor includes a housing having a through passage along which chemical can flow, a sidewall of the housing having first and second openings that communicate with the through passage. A first electrode is mounted on the housing and aligned with the first opening, the first electrode of a plate configuration with a unitary depression that extends through the first opening and to a peripheral edge of the through passage. A second electrode is mounted on the housing and aligned with the second opening, the second electrode of a plate configuration with a unitary depression that extends through the second opening and to the peripheral edge of the through passage. A method of detecting presence or absence of chemical is also provided.

Abstract: A warewash machine includes in-situ tank soil load reduction that involves at least one of: (i) prior to addition of fresh water, draining the collection tank via a path that exits the collection tank at a location lower than a primary overflow path until wash liquid level in the collection tank drops below a standard operating level, and thereafter adding fresh water; or (ii) draining the collection tank via a path that exits the collection tank at a location lower than a primary overflow path while simultaneously adding fresh water; or (iii) adding fresh water such that wash liquid level in the collection tank rises above a standard operating level, and thereafter carrying out draining of the collection tank.

Abstract: A warewash machine includes at least one collection tank for collecting wash liquid that is recirculated by a pump and sprayed for cleaning wares within a spray zone of the machine. An overflow path leads from the collection tank, and an automated valve controls flow along the overflow path.

Abstract: A warewash machine includes a housing at least in part defining a chamber for cleaning wares and a sump for collecting hot cleaning water that is recirculated through the chamber during cleaning A drain path is provided for draining cleaning water from the sump and a fresh water input line includes at least a fresh water input that receives fresh water. A waste water heat recovery arrangement includes one or more plate heat exchanger units that transfer heat from the draining cleaning water to the incoming fresh water.

Abstract: A warewash machine includes a sump for collecting hot cleaning water that is recirculated in the chamber during cleaning, a drain path for draining cleaning water from the sump and a fresh water input line including at least a fresh water input that receives fresh water. A waste water heat recovery arrangement includes a plurality of heat exchange compartments arranged in series flow communication and forming part of the drain path. A waste water input is associated with a first of the heat exchange compartments and a waste water output associated with a last of the heat exchange compartments. Waste water at least partially fills each of the heat exchange compartments. At least part of the fresh water input line passes through each of the heat exchange compartments. Heat from waste water is transferred to fresh water in the drain line within each heat exchange compartment.

Abstract: A flow through chemical sensor includes a housing having a through passage along which chemical can flow, a sidewall of the housing having first and second openings that communicate with the through passage. A first electrode is mounted on the housing and aligned with the first opening, the first electrode of a plate configuration with a unitary depression that extends through the first opening and to a peripheral edge of the through passage. A second electrode is mounted on the housing and aligned with the second opening, the second electrode of a plate configuration with a unitary depression that extends through the second opening and to the peripheral edge of the through passage. A method of detecting presence or absence of chemical is also provided.

Abstract: The timing of warewash machine delime operations may be set according to one or more of water used in the machine or one or more machine characteristics. A delime process that utilizes intermittent shock delime operations is also provided.