Quick answer: The Intermatic T104M (~$70–$120) is the best all-around timer for a pool heat pump — it’s a 24-hour mechanical dial timer rated up to 40A and 5HP that’s been the de facto standard on pool equipment pads for decades, according to pool-supply retailers like Leslie’s and In The Swim who stock it as their default replacement part. For higher-horsepower heat pumps on a 208-277V circuit, the Woods 59104WD matches that same 40A/5HP rating in an indoor-rated enclosure. If you want app control and remote scheduling instead of a manual dial, the DEWENWILS Smart WiFi Timer Box (2HP-3HP, 40A) adds Alexa and Google Assistant compatibility without needing an electrician to wire in a smart switch.
Most gas pool heaters don’t need a separate timer at all — their own control board and thermostat handle ignition and shutoff. Timers become relevant mainly for heat pumps and pump/heater combo circuits, where running the equipment only during set hours saves electricity and avoids leaving a heat pump’s compressor cycling all day. We compared four timers below on HP rating, indoor/outdoor rating, and control style.
Best pool heater timers at a glance
| Timer | Type | Max rating | Best for | Price |
|---|---|---|---|---|
| Intermatic T104M | Mechanical dial | 40A / 5HP, 208-277V | Best overall | ~$70–$120 |
| Woods 59104WD | Mechanical dial | 40A / 5HP, 208-277V | High-HP heat pumps | ~$45–$65 |
| DEWENWILS Smart WiFi Timer Box | App / WiFi | 40A / 2-3HP, 120-277V | Remote/app control | ~$50–$70 |
| DEWENWILS Mechanical Timer Box | Mechanical dial | 40A / 2HP, 120-277V | Best budget | ~$30–$45 |
1. Intermatic T104M — Best Overall
Intermatic T104M 24-Hour Mechanical Time Switch
- The mechanical timer most pool-supply stores stock as their default replacement part — Intermatic has made the T104 line for decades and it's the closest thing to an industry-standard pool equipment timer.
- DPST (double-pole single-throw) switching handles the higher current a heat pump or 240V pump/heater combo circuit draws, rated to 40A general use and up to 5HP.
- 15-minute trippers on the 24-hour dial let you set multiple on/off windows per day without any programming — push a tripper down for "on," pull it up for "off."
- Sold as a mechanism-only unit or in an outdoor enclosure kit — confirm which variant you're buying, since the bare mechanism needs an existing outdoor timer box to mount in.
The T104M is the timer we’d point most heat-pump owners to first — it’s simple, doesn’t depend on WiFi or an app to keep running, and parts availability is excellent if a dial or tripper ever wears out. Want to get one on the pad before your next scheduled cleaning? Try Amazon Prime free for 30 days and get two-day delivery instead of waiting on standard shipping.
2. Woods 59104WD — Best for High-HP Heat Pumps
Woods 59104WD Indoor 24-Hour Heavy-Duty Mechanical Time Switch
- Matches the Intermatic T104M's 40A/5HP/208-277V rating at a lower typical price point, making it a solid alternative when you just need the electrical spec, not the Intermatic name.
- DPST mechanical dial with 15-minute trippers, same basic operating principle as the T104M — no programming, no batteries to fail.
- Indoor-rated enclosure by default; Woods also sells an outdoor NEMA 3R version (59104RWD) if the timer needs to mount outside without an existing weatherproof box.
- A straightforward swap-in replacement if an older mechanical timer on the pad fails and you don't want to change the wiring.
For a heat pump pulling close to its rated max current, the Woods 59104WD’s 5HP headroom matters more than which brand name is on the dial — it’s electrically interchangeable with the T104M for most pool equipment pads.
3. DEWENWILS Smart WiFi Timer Box — Best App/Remote Control
DEWENWILS Outdoor Smart WiFi Pool Pump Timer Box
- Adds app-based scheduling, on-demand remote on/off, and Alexa/Google Assistant voice control — useful if you want to adjust the heater's schedule without walking out to the equipment pad.
- Sold in both 2HP (120-277V) and 3HP (240V) versions — match the model to your heat pump's actual amp draw and voltage, not just whichever is cheaper.
- Weatherproof outdoor enclosure with a sealed cover, ETL-listed for outdoor pool equipment use.
- Depends on a home WiFi connection to change settings remotely; the physical timer keeps running its last programmed schedule if WiFi drops, but you lose app control until it reconnects.
If your pool already runs on smart-home-connected pump or filter automation, pairing a DEWENWILS smart timer with the heater keeps the whole schedule adjustable from one app instead of a mechanical dial you have to walk out and re-set by hand. For a heater-brand comparison of what “smart control” actually means — built-in Wi-Fi versus a separate automation panel — see our pool heater automation guide.
4. DEWENWILS Mechanical Timer Box — Best Budget
DEWENWILS Heavy-Duty Mechanical Pool Pump Timer Box
- The lowest-cost heavy-duty option here, with a pre-wired outdoor box that skips buying a separate timer mechanism and enclosure separately.
- 2HP maximum rating is enough for most single-speed pumps and smaller heat pumps, but check your unit's nameplate current before buying — it's the lightest-duty timer on this list.
- 24-hour mechanical dial with the same tripper-based on/off setting as the Intermatic and Woods options, no app or WiFi required.
- Comes pre-assembled in its enclosure, which makes it a faster install than a bare timer mechanism that needs its own box.
For a smaller heat pump or a straightforward pump-only timing job, the DEWENWILS mechanical box covers the same core function as the pricier options for less — the tradeoff is the lower 2HP ceiling and no app control.
How to pick: HP rating, voltage, and mechanical vs. smart
The rating that actually matters is amps and horsepower relative to your equipment’s nameplate, not brand. Check the heat pump or pump’s data plate for its rated current and voltage (commonly 120V, 240V, or 208-277V on larger heat pumps) and buy a timer rated at or above that — undersizing a timer’s contacts is a fire risk, not just a warranty issue. All four timers above are rated 40A, but their HP ceiling varies from 2HP to 5HP depending on voltage, so match the spec, not just the amp number.
Mechanical dial timers (Intermatic, Woods, DEWENWILS mechanical) win on simplicity and reliability — there’s no firmware, no app, and no WiFi dependency, which is why they remain the default on most pool equipment pads. A smart WiFi timer box trades a small amount of that simplicity for remote scheduling and voice control, which matters more if you’re already running other smart-home-connected pool equipment. For the electrical side of a heater install in general, see our pool heater installation cost guide; for keeping the whole system running efficiently, see our maintenance schedule.
The bottom line
For most heat pump owners, the Intermatic T104M is the safe default — it’s the timer pool professionals reach for first, with wide parts availability if anything needs replacing years down the line. The Woods 59104WD delivers the same 5HP/208-277V spec for less if the brand name doesn’t matter to you. Want remote scheduling instead of a manual dial? The DEWENWILS Smart WiFi Timer Box adds app control without an electrician rewiring anything, and the DEWENWILS Mechanical Timer Box covers smaller 2HP setups at the lowest price of the four.