What is Maximum Inlet Temperature in Pressure Washers (and why does it matter?)
The "Maximum Inlet Temperature" specification on a pressure washer chart denotes the highest temperature of the water that can be safely fed into the pressure washer system. The “Maximum Inlet Temperature” figure holds critical importance as exceeding this threshold can lead to detrimental consequences, particularly concerning the internal components of the pressure washer, notably the pump. For instance, most cold water pressure washers are engineered to accommodate a maximum water inlet temperature of 40°C (104ºF). Therefore, the water supplied to most cold water pressure washers should not surpass 40ºC to ensure optimal operation and longevity of the equipment.
Reasons for Specifying Maximum Inlet Temperature:
1. (Primary Reason) Preventing Damage to Internal Seals and Components:
The pump, valves, and various internal components of a pressure washer contain seals and gaskets made of rubber or plastic. Exposure to excessively high water temperatures can cause these seals to expand, deform, or deteriorate, leading to leaks and diminished performance.
2. Maintaining Proper Cooling of the Pump:
Water flowing through the pressure washer pump serves, in part, the function of cooling it during operation. Elevated inlet water temperatures increase pump temperatures, potentially resulting in overheating and premature failure of seals or other vital components.
3. Avoiding Boiling Water Inside the System:
Standard residential pressure washers are not designed to handle boiling water or steam. Introducing water above the maximum inlet temperature threshold could induce boiling or steam formation inside the pump, compromising performance, and posing safety hazards.
4. Material Limitations:
The metals, plastics, and rubber utilised in typical pressure washer construction have temperature limitations beyond which they may degrade, warp, or fail prematurely when subjected to excessive heat from the inlet water.
Incorporating the Ehrle KS Series Exception:
It's noteworthy to mention exceptions to the typical maximum inlet temperature specification of 40°C, such as the Ehrle KS series (KS 823 and KS 1140), which boast a higher water inlet temperature of 80°C. These models are specifically engineered to accommodate hotter inlet water temperatures, thereby expanding their range of applications without compromising performance or risking damage to internal components.
Summary
The maximum inlet temperature rating serves as a safeguard for internal seals, facilitates proper pump cooling, prevents boiling within the system, and ensures the materials can withstand the heat from the water supply. Exceeding this temperature threshold can result in severe damage to pressure washers not explicitly designed for hot water operation.
By adhering to the specified maximum inlet temperature, users can optimise the performance and durability of their pressure washer equipment while mitigating the risk of costly repairs or replacements.