UCEDER Hot Tub LX H20-Rs1 Thermostat 110V 2kw with Adjustable Temperature Thermostat for Some hot tubs,Underground Small Pool &Bathtub（Suggest Connect 20A Adapter or Breaker

This thing is great but it’s not made for small pools so you’ll need to be crafty. I have mine connected to a 10x30 pool and is heated to 84-88 degrees. First it’s meant to be hardwired for 20amps but I put a 15amp plug on it which is plugged in to a 15amp GFCI outlet and have not had any power issues. Make sure to put the white wire on the proper side. Examine your outlet if you need to. Next, the PVC couplings, be prepared to spend time finding the parts to connect your pool hoses but it can be done relatively cheap at your hardware store. Also, metal o-ring clamps will help a lot to eliminate any leaks. I upgraded to a stronger pump filter, it’s still not quite enough to trigger the flow lever. Others have added a metal washer to create a bit more surface area but I decided to super glue a lego brick under it which means I have to be very careful and ensure it’s only plugged in when the pump is running otherwise it will pop the heater’s hot circuit (under the little screw cap) and potentially break the unit. This is how I broke my first unit. The most important concept to consider is the relationship between heating your pool and water flow. As water is flowing through, the water is picking up a little bit of heat from the coils each time and then going back in the pool and sharing that little bit of heat with the rest of the pool. The little pump will not move the water fast enough to warm the pool. I upgraded to the 1500 gph and to 1.5” hoses using hose adapters. You also should start with warm water otherwise it’s 2-3 days of running 24 hours to get the pool warm. After it’s warm it needs about 6-8 hours a day to keep it warm and surprisingly I didn’t see a huge difference in my power bill. Last connect to output of the filter pump; after the water has been filtered. No need to get leaves and dirt stuck on the heating element. Good luck.

I used this in conjunction with "Key Lander Hot Tub Spa Circulation Pump; 48Frame LX Motor" pump. the inlet and outlet is 3/4 in AND it is just enough water flow to activate the heater. YES. There is a minimum flow and the pump above is what is needed. It is barely enough (going through 3/4 ingress and egress). If the filter get clogged, the heater will NOT turn on. We are using the pump and heater above to replace the all in one unit for the inflatable intex hot tub. It works great with some PVC pipe and fittings and the existing hotub. I use a thermostat (arduino microcontroller) to turn the pump on and off, which in turn turns on the pump when the temperature is too cold, and turns the pump off when it is at the right temperature.

Bought this based off other reviews online that mention it works on smaller hot tubs and mini above ground pools. I fully understand that it will take FOREVER to heat up. Now, this does heat up our 8x2 stock tank pool but I feel it is not powerful enough for that amount of water. It is hooked up to its own 20a circuit with a short 12Ga chord to the outlet 10' away. I use a 12" sand filter pump and 1.5" piping from pump/heater to pool. Heater runs how it should and temperature selection dial works perfectly. Chords and connectors stay cool and do not run hot. Plenty of water flow to turn on the pressure switch inside the heater, and it does indeed pull close to 18amps while running. I measure roughly 1-2 degree of temperature difference from water coming in and the water coming out of heater, which is not as much as I thought it would do. With water temp at 75 degrees, the heater will heat the stock tank roughly 0.75 degrees an hour with ambient temperature outside in the mid 80's. Slow enough that it is hard to tell if the temperature is being raised simply by the ambient air. I decided to try this out early in the morning at 5 AM while the air temp was in the low 60's. I had the same results of it heating the 8x2 stock tank of roughly les than 1 degree per hour. So it does heat up.... HOWEVER if you heat your pool hot enough to match the temp of a hot tub (100 degrees) with some other means like propane and try to use this to keep the pool at its current temp, it will struggle to keep up and the pool temp will drop. With the stock tank heated to 100 degrees the heater could not keep up and the temp easily went down 3-4 degrees within an hour. This was done while ambient air temp was in the mid 80's Do not even attempt to try this when the air temp is in the 50's... In short this will work with very small stock tank/pools, much smaller than 8x2. 8x2 and larger it is not powerful enough if you want to use it like a spa heater, better off to use it from freezing in the winter. Save your money.

Si lo que necesitas es calentar el agua de tu spaa rápidamente esta no es la mejor opción, pero con un poco de paciencia mi spaa de 2,500 litros alcazó una temperatura de 40 C en 16 hrs y resolvió perfecto el tema de calentamiento de agua justo a la medida de mis necesidades.

You are thinking about this product because you have an old hot tub and the only other heater replacement options are near $1,000. You do need some plumbing and electrical knowledge to install this safely. If you haven't ever installed a light switch or a sink or toilet, then definitely seek some professional help). I read many of the reviews before purchasing this, and that really helped my piping and installation plans to be efficient. It still took me an hour getting parts, and about 90 minutes to install. One of my main recommendations is to avoid barb fittings and clamps. These just aren't intended for permanent solutions where there's high pressure in the pipes. Using couplings and PVC cement (which is just a rub on glue) is easy. I'm also not a fan of people manipulating the pressure safety switch (that's a fire risk). If you don't have a strong enough pump, as described by the vendor, then don't use this. Fittings: forget the hardware and plumbing stores - go to a pool specialty store. I got everything I needed in one stop. The half union threads are specific to pools and spas - you will need to attach a coupling or reducer or elbow to that piece that comes off of the heater before you add pipe. You may need 2-in to 1 1/2-in reducers, those are at these stores. I highly recommend the flexible PVC pipe (it's like $5/ft) - it's very stiff, but it's certainly easier than perfectly planning your pipe installation and lengths and rotations. You can see from my pic I had a rather complicated piping because of the direction this heater needs to be installed (that's my only minor complaint of this product). In the end, this heated my 900 L hot tub to 100 F, from cold, overnight and seems to be holding that temperature pretty steadily.

No sirve, nunca funcionó . No tiren su dinero

Had electrician do install today and it's been running for a couple of hours. No noticeable difference in temeperature from the inlet line at 74F to outlet line still 74F or perhaps a 1/2 degree increase. I expected to see increase of at least a couple degrees. Electrical contacts all checked and working fine, just not much heat with the temperature control set at 40. I probably should have purchased a 240V heater with better heating capacity. As of today I have a new report. The little heater raised the water temperature by 6 degrees in 4 hours. Much better than I first reported. It doesn't seem to be returning much heat, however the return line is much different than an inground pool. The return line water mixes with the pool in the water rapidly making it a little difficult to notice an difference. However over time it does the job. I have a solar cover on the pool, with that and the little heater I expect to see a rise of 12 degrees today if my calcs are correct.

Easy install. Works per description.