Intermatic T104 Timer Review: Durable but Needs Care
A surprising takeaway from user feedback is just how long the Intermatic T104 24-Hour Mechanical Timer Switch can last when properly installed—reports of units running for 15, 17, even 20+ years are common. Scoring an impressive 8.6/10 across platforms, it’s widely regarded as a dependable workhorse for pool pumps, heaters, and other high-load applications, though recurring issues with timer motors and mechanical wear do appear in long-term use.
Quick Verdict: Conditional Yes — Ideal for users comfortable with basic electrical work or willing to hire a pro. Highly praised for durability and ease of installation, but expect mechanical wear over time.
| Pros | Cons |
|---|---|
| Long service life (10–20+ years reported) | Timer motor can fail prematurely |
| Easy installation for experienced users | Mechanical parts can wear, causing switch failure |
| Handles heavy loads up to 40A | Limited to 1-hour minimum on/off intervals |
| Manual override for flexibility | Not suitable for those wanting fine-grained scheduling |
| Fits existing Intermatic enclosures | Outdoor use requires proper enclosure for weather |
| Cost-effective replacement | Occasional incorrect frequency/motor issues |
Claims vs Reality
The manufacturer promotes “direct 24-hour control of most loads” with up to 12 on/off operations daily. This claim holds up strongly in real-world use. A verified buyer on Amazon noted: “Had one on my swimming pool for 15 years… replaced it with the same model. Runs like a champ.” Reddit users also confirmed that it “works perfectly for controlling my pump” and “handles my salt pool system” without issue.
Another selling point is its “manual override” for immediate control. Users consistently found this feature practical—especially for adjusting schedules during maintenance or unexpected changes. One Amazon reviewer shared: “You can set up several on/off scenarios very quickly and easily, manually.”
Durability is a key marketing claim. While many users back this up with decades-long service stories, some note that the timer motor can fail well before expectations. A Trouble Free Pool contributor explained: “The motor is not strong enough anymore to turn the switch… good thing is easy to change.” This reveals a maintenance reality: longevity depends on occasional part replacement.
Cross-Platform Consensus
Universally Praised
Across Amazon, Trustpilot, and Reddit, ease of installation stands out. For pool owners or DIY-savvy homeowners, this means minimal downtime. A verified buyer on Amazon reported: “Took about an hour to do… saved at least a hundred dollars just doing it myself.” Another said: “I had it installed in under 10 minutes.”
Durability under outdoor conditions also earns praise. Many have run the T104 in exposed pool pump enclosures for over a decade. “I had this exact timer for my pool pump outside for 12 years or more,” one Amazon user commented, highlighting weather resistance when paired with proper housing.
The timer’s load capacity (40A, up to 5 HP motors) reassures users managing demanding equipment. Reddit user feedback emphasized that it’s “240v 40a and can easily kill you or start a fire if you don't know what you’re doing”—a caution, but also a testament to its capability for serious electrical loads.
Common Complaints
Mechanical wear is the most frequent frustration. Trouble Free Pool users described the timer dial failing to push the main switch due to weakened motors or stripped gears. One Reddit comment warned: “Timer fails prematurely,” with some motors lasting only a few years before replacement.
Minimum on/off intervals of one hour limit flexibility. This is fine for pool filtration cycles but frustrates those wanting shorter, more frequent control. A 4-star Amazon review advised: “Need to provide more clips so as to set more on/off times.”
Occasional quality control issues appear. A small number of users received incorrect frequency units or had timers “freeze” within a year, leading to early replacements.
Divisive Features
Manual override is beloved by those who value immediate control, but irrelevant to users who never deviate from set schedules. Similarly, the mechanical design is praised for simplicity and repairability, yet some wish for digital precision or Wi-Fi connectivity. As one Reddit user mused: “I’ve been considering replacing with a WiFi timer so I can control pump remotely.”
Trust & Reliability
Trustpilot and Amazon reviews show high confidence in authenticity, with few scam concerns. Sellers offering genuine Intermatic units often receive praise for fast shipping and accurate descriptions. “Package arrived on time, in perfect condition and as described,” one reviewer confirmed.
Long-term reliability is a defining strength. Multiple users replaced timers only after decades of service, often reusing the original enclosure. Reddit contributors advise keeping a spare mechanism on hand, especially for seasonal pool use, to avoid downtime during peak months.
However, mechanical wear is unavoidable. Community wisdom suggests snapping out the old mechanism and swapping a new one into the enclosure—minimizing cost and avoiding full rewiring.
Alternatives
Alternatives mentioned in user discussions include Wi-Fi-enabled timers for remote control, often around $50. While these offer connectivity and app control, Reddit users question their long-term durability compared to mechanical models. One Trouble Free Pool member noted resistance to switching to digital: “I don’t think the lifespan is any better.”
Price & Value
On eBay, new units range from $59.95 to $94.99, with used mechanisms as low as $25. Amazon buyers often find them cheaper than local hardware stores. This price point makes DIY replacement attractive—saving hundreds compared to professional installation quotes of $325.
Resale value for working used units remains strong due to compatibility with existing Intermatic enclosures, appealing to budget-conscious buyers.
FAQ
Q: Can the T104 control both a pool pump and heater?
A: Yes, it’s designed to coordinate heater and pump operations, turning off the heater about 20 minutes before the pump to prevent overheating damage.
Q: How many on/off cycles can it handle daily?
A: Up to 12 cycles with a minimum interval of one hour between changes.
Q: Is it safe for outdoor installation?
A: Only with the appropriate weatherproof enclosure. Many users report over a decade of outdoor service when housed properly.
Q: How hard is it to install?
A: For those with electrical experience, installation can take 10–30 minutes. Novices should hire a professional due to high voltage risks.
Q: What’s the most common failure point?
A: The timer motor or internal gears, which can weaken over time and fail to engage the main switch.
Final Verdict: Buy if you’re a pool owner or equipment manager looking for a proven, heavy-duty mechanical timer and are comfortable with basic electrical work or have access to a professional installer. Avoid if you need fine-grained scheduling or remote control. Pro tip from the community: keep a spare mechanism on hand for quick swaps during peak season.
