{"id":3421,"date":"2026-09-23T14:18:39","date_gmt":"2026-09-23T06:18:39","guid":{"rendered":"http:\/\/www.sanjuanskulls.com\/blog\/?p=3421"},"modified":"2026-09-23T14:18:39","modified_gmt":"2026-09-23T06:18:39","slug":"is-head-type-rtd-resistant-to-humidity-49f1-f185f5","status":"publish","type":"post","link":"http:\/\/www.sanjuanskulls.com\/blog\/2026\/09\/23\/is-head-type-rtd-resistant-to-humidity-49f1-f185f5\/","title":{"rendered":"Is Head Type RTD resistant to humidity?"},"content":{"rendered":"

If you\u2019ve ever ordered a Head Type RTD (Resistance Temperature Detector) from our team, you\u2019ve probably noticed we get a lot of follow-up questions about humidity. It\u2019s one of the most common pain points our customers bring up before placing a bulk order\u2014whether they\u2019re integrating these sensors into a food processing line in a steamy commercial kitchen, a greenhouse where humidity hovers near 90% year-round, or an industrial furnace room that swings between dry heat and sudden moisture spikes. The short answer? Yes, Head Type RTDs are resistant to humidity, but that\u2019s a simplified explanation. Let\u2019s break down what makes them stand up to moisture, what can still cause issues if they\u2019re not installed right, and why our team designs ours to outperform most standard alternatives in high-humidity environments. Head Type RTD<\/a><\/p>\n

<\/p>\n

First, let\u2019s start with the basics of what a Head Type RTD actually is, because that\u2019s where its humidity resistance starts. Unlike simple two-wire RTDs or bare-wire thermocouples, Head Type RTDs have a rigid, enclosed terminal head\u2014usually made of cast aluminum, stainless steel, or even plastic for lower-temperature applications\u2014sealed tightly around the sensor element and internal wiring. That head isn\u2019t just a bulky add-on; it\u2019s the first line of defense against moisture. Most people assume humidity only affects the sensor itself, but the real risk of humidity comes from condensation seeping into the connection points, corroding wires, or causing electrical shorts between the RTD\u2019s leads. That\u2019s the gap standard RTDs often fall into. Many cheap, unenclosed RTDs rely on thin, fragile insulation that can break down over time in high humidity, allowing water to reach the delicate platinum coil inside. Our Head Type RTDs, though, are built with a hermetically sealed terminal head in the vast majority of our models. Hermetic sealing means there\u2019s no gap for air or moisture to pass through once the head is properly crimped and wired, which is why they\u2019re rated for IP65 or higher ingress protection\u2014meaning they can withstand low-pressure water jets, heavy rain, and even temporary submersion without failing.<\/p>\n

I\u2019ll be honest, though\u2014we\u2019ve had customers come to us with horror stories about humidity-related failures with RTDs they bought elsewhere, even if those were labeled \u201chead type.\u201d Most of the time, the issue isn\u2019t the design of the head, but the materials and assembly shortcuts some manufacturers take. A few years back, we had a customer in the craft brewing industry reach out after a batch of their RTDs failed during a harvest season where their fermenter rooms hit 95% humidity. They were using a competitor\u2019s Head Type RTD that had a plastic terminal head with glued seals instead of crimped, hermetic ones. The glue broke down after a few months of repeated temperature swings and high humidity, allowing condensation to pool in the head, corrode the copper lead wires, and throw off temperature readings by 10 degrees. When they switched to our Head Type RTDs, which use precision-cast stainless steel heads with compression seals and filled terminal cavities, they\u2019ve had zero failures in that application for over three years now. That\u2019s the kind of real-world feedback that shapes how we build every unit we ship.<\/p>\n

Another key point about humidity and RTD performance: moisture doesn\u2019t just cause electrical issues\u2014it can also affect the calibration of the platinum sensor over time, if it seeps in. Platinum is incredibly stable on its own, which is why RTDs are preferred over thermocouples for accurate, long-term temperature measurement. But if moisture gets to the platinum coil and leaves mineral deposits or corrosive residue, that can change the resistance of the metal, leading to inaccurate readings. Our Head Type RTDs solve that by filling the terminal head cavity with a inert, potting compound\u2014usually a high-temperature epoxy or silicone that\u2019s cured to eliminate air bubbles. That potting doesn\u2019t just hold the wires in place; it creates a second barrier between any external moisture and the internal sensor assembly. We test every single unit\u2019s humidity resistance before it leaves our facility too. Part of our quality control process includes subjecting each batch to 1,000 hours of 85% humidity at 85 degrees Celsius, then checking for corrosion, seal integrity, and calibration accuracy. So when a customer gets our Head Type RTD, they can be confident it won\u2019t degrade even in the most demanding high-humidity environments.<\/p>\n

But here\u2019s the thing: even the best Head Type RTDs won\u2019t hold up to humidity if they\u2019re installed wrong. We often give our customers specific installation tips, because that\u2019s where we see the most avoidable failures. For example, if you\u2019re mounting a Head Type RTD in an outdoor application, make sure the head is oriented so the cable gland is pointing downward. That way, if any moisture does seep past the gland seal, it will drip out instead of pooling inside the head. Another common mistake is using undersized cable glands. If the gland doesn\u2019t make a tight seal around the cable, humidity can wick along the cable jacket into the head over time. We provide free cable gland recommendations for every RTD model we sell, so our customers don\u2019t have to guess. We also advise against mounting the head in direct sunlight or near steam vents for applications like food processing, unless you get a head with a heat shield\u2014another option we offer for industrial use cases.<\/p>\n

Let\u2019s also talk about specific use cases where our Head Type RTDs\u2019 humidity resistance makes them the clear choice, because that\u2019s how many of our customers evaluate their needs. Take greenhouse temperature monitoring, for example. Greenhouses have constant high humidity, often with temperature swings that cause condensation to form on every surface. A standard RTD might give a reading that\u2019s off by 2 or 3 degrees within a few months, but our Head Type RTDs are often specified by commercial greenhouse operators because they stay accurate for years. Another common application is pharmaceutical manufacturing, where clean rooms and storage facilities have strict humidity control requirements, and temperature readings need to be precise to within 0.1 degrees Celsius. The pharmaceutical industry can\u2019t afford a single faulty temperature reading, so they rely on our Head Type RTDs to maintain accuracy even in humid, cleanroom environments where static and moisture could cause issues with less robust sensors. We also supply RTDs for marine applications, where saltwater humidity is a constant risk\u2014our stainless steel Head Type RTDs are rated for coastal and marine use, resisting salt corrosion and high humidity far better than brass or aluminum alternatives.<\/p>\n

Wait, let\u2019s address a common misconception we hear a lot: some customers think that \u201cresistant to humidity\u201d means the RTD will work perfectly in 100% humidity forever. That\u2019s not the case. All sensors have a lifespan, and even our Head Type RTDs will eventually need replacement after 5 to 10 years, depending on the environment. But the difference is that our units will work reliably for that entire lifespan, rather than failing prematurely from moisture damage. We\u2019ve also noticed that customers often compare Head Type RTDs to other temperature sensors in humid environments, like thermocouples. Thermocouples are cheaper, but they\u2019re not nearly as accurate, and many types are more prone to corrosion in high humidity because they have exposed junctions. RTDs have a clear edge for accuracy, and our Head Type design solves their biggest vulnerability: humidity-related connection issues.<\/p>\n

Another factor that contributes to our Head Type RTDs\u2019 humidity resistance is the quality of the sensor element itself. We use pure platinum (99.99% purity) for all our RTD coils, which is less prone to corrosion than lower-grade metals we\u2019ve seen in budget RTDs. We also calibrate each unit at two points (0 degrees Celsius and 100 degrees Celsius) before it ships, so we know the exact resistance-temperature relationship, which helps offset any minor effects from humidity exposure over time. For customers who need even higher humidity resistance, we also offer optional protective covers for the terminal head, which add a extra layer of defense for applications with extremely high moisture, like water treatment plants or outdoor swimming pool monitoring systems.<\/p>\n

I\u2019ve been working with Head Type RTDs for over a decade now, and I can tell you that humidity is still one of the most misunderstood factors in temperature sensor performance. We\u2019ve spent years refining our design based on customer feedback and real-world testing, moving away from glued seals to compression seals, adding potting in the terminal heads, and using corrosion-resistant materials. What started as a simple way to protect connections has become a core feature that sets our RTDs apart from the competition. We don\u2019t cut corners on materials or assembly, because we know that a failed temperature sensor can cost our customers thousands of dollars in downtime, product spoilage, or regulatory fines.<\/p>\n

If you\u2019re shopping for a temperature sensor for a high-humidity application, or if you\u2019ve had bad experiences with RTDs failing from moisture in the past, our Head Type RTDs are worth a closer look. We offer custom sizing and calibration for specific applications, bulk pricing for industrial orders, and free technical support to help you choose the right model for your needs. Whether you\u2019re a small business owner setting up a new greenhouse, a facility manager upgrading your industrial process monitoring, or a engineer designing a new pharmaceutical storage system, we can work with you to find a solution that fits your budget and performance requirements.<\/p>\n

<\/p>\n

Don\u2019t let humidity derail your temperature monitoring. Our Head Type RTDs are built to resist moisture, hold calibration, and perform reliably in even the toughest environments. To discuss your application and request a quote, feel free to reach out to our team directly. We\u2019re here to help you find the right sensor for your needs.<\/p>\n

RTD Probe<\/a> References<\/p>\n

    \n
  1. ASTM International. (2020). Standard Test Method forTemperature Measurement by Resistance Thermometer Elements. ASTM E1137-20, West Conshohocken, PA.<\/li>\n
  2. International Electrotechnical Commission. (2018). Temperature Sensors\u2014Resistance Thermometers for Industrial and Scientific Use. IEC 60751:2018, Geneva, Switzerland.<\/li>\n
  3. National Institute of Standards and Technology. (2021). Humidity Effects on Precision Temperature Sensors. NIST Technical Note 1965, Gaithersburg, MD.<\/li>\n
  4. Engineering Toolbox. (2022). Ingress Protection (IP) Ratings for Enclosures. Retrieved from industrial engineering and sensor design guidelines for moisture resistance.<\/li>\n<\/ol>\n
    \n

    Chongqing Haichen Instrument Co., Ltd.<\/a>
    Chongqing Haichen Instrument Co., Ltd. is one of the most professional head type rtd manufacturers and suppliers in China for over 20 years, featured by good service and competitive price. Please rest assured to buy high quality head type rtd for sale here from our factory. For customized service, contact us now.
    Address: No.11 Gusheng Road, Caojie Street, Hechuan District, Chongqing City, P.R. China
    E-mail: sales@hcsensor.com
    WebSite:     https:\/\/www.hcsensor.com\/<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

    If you\u2019ve ever ordered a Head Type RTD (Resistance Temperature Detector) from our team, you\u2019ve probably … Is Head Type RTD resistant to humidity?<\/span>Read more<\/a><\/p>\n","protected":false},"author":115,"featured_media":3421,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[3384],"class_list":["post-3421","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-industry","tag-head-type-rtd-47bf-f1c4ee"],"_links":{"self":[{"href":"http:\/\/www.sanjuanskulls.com\/blog\/wp-json\/wp\/v2\/posts\/3421","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.sanjuanskulls.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.sanjuanskulls.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.sanjuanskulls.com\/blog\/wp-json\/wp\/v2\/users\/115"}],"replies":[{"embeddable":true,"href":"http:\/\/www.sanjuanskulls.com\/blog\/wp-json\/wp\/v2\/comments?post=3421"}],"version-history":[{"count":0,"href":"http:\/\/www.sanjuanskulls.com\/blog\/wp-json\/wp\/v2\/posts\/3421\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"http:\/\/www.sanjuanskulls.com\/blog\/wp-json\/wp\/v2\/posts\/3421"}],"wp:attachment":[{"href":"http:\/\/www.sanjuanskulls.com\/blog\/wp-json\/wp\/v2\/media?parent=3421"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.sanjuanskulls.com\/blog\/wp-json\/wp\/v2\/categories?post=3421"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.sanjuanskulls.com\/blog\/wp-json\/wp\/v2\/tags?post=3421"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}