Honeywell Home RLV4305A1000 5-2 Day Programmable Thermostat for Electric Baseboard Heaters

Firstly lets quickly get this out of the way.This is a LINE Voltage thermostat.The simplest way to describe this is -its a light switch.. just switches on when it hits the temp to kick of or off.So if you're seeing 3 or 4 super thin wires this isnt the right item for you...That being said - my home is basically a hot water boiler hooked up to 2 zones and zone control is either powering on or off these water circulators.Its just a simple 120v line.I replaced two analogue mercury style thermostats and hook up is straight forward and dummy proof.The first thing before you start the replacement ... TURN OFF the Power at the breaker!This is line voltage or 120v will be uncomfortable.. or if you're 240v... yeah don't want to touch a live wire there....The thermostat is NOT polarity sensitive. That means you can join either the hot or neutral to either black wire - complete the circuit and shove everything back in.For me I used standard Wagos rather than nut connectors and replacing both thermostats was a breeze.I did have an issue with the FIRST one I bought from a big box store. The unit kept on rebooting which every 4 minutes throws out a 2.5 and 11.9 code.I tried to search what these codes mean but on the 2nd and replacement installs I noted i get these codes ON boot but the working ones just never showed those codes after boot.The Amazon shipped unit worked flawlessly and I was able to return to the big orange box store with no issues.So for anyone with LINE voltage heating or cooling - this is a great thermostat to program your wake up away and sleep ranges for the temps in the home. Better than 1 setting regardless of there is a human home or not.Super Easy DIY - just work safe! have fun!!

I have been using this thermostat now for about a month. If you have the skill to change an in wall light switch, you can install this thermostat. I use mine to control an oil filled roll around type radiator style space heater. You cannot use this thermostat, or any other external thermostat if your heating unit has a built in electronic control. Manual contols only! (switches & turnable more or less heat knob).This thermostat is completely quiet, fairly easy to enter settings, (read the instruction sheet until you understand) and controls room temperature within a degree. The room temperature showing on the display is not as accurate as the temperature control cirquit, and is an unimportant aspect of this very accurate controller. Want dead on RTD type reading? Triple the cost of this thermostat! Mine reads 2 degrees high. So I set it at 70 instead of 68°. What is important is the industrial accuracy RTD tyle lab calibration temperature sensor on my night stand.(I'm a retired Energy Management/Automation controls Engineer with 38 years experience) This thermostat works very well.15 second cyle, 15 minute cycle? Fan, no fan? This thermostat uses one or the other methods to control the electric heating element. The 15 minute cycle is used with heaters that also have fans in them. It runs for upwards of 15 minutes and cycles off to maintain the temperature. The 15 second cycle only controls the heating element. It uses a solid state switch (triac) to pulse the heat element on or off to closely ccontrol the room temperature. At near setpoint, this unit pulses power at 1 second on, 14 seconds off. If the room is way below setpoint, the heater will be on continuosly untill the room temperature approaches the setpoint, then starts by pulsing 14 seconds on, 1 second off, all the way to completely off at setpoint. This is standard electric heating (no fan) control with much higher accuracy. Been around for 30 plus years, but very expensive untill the past few years. This kind of pulsing is harmless to heater elements.I used a shallow surface mount wall box, surface mount wire/cable wall guides (2), mounted box 5 feet above a wall outlet, used a 20 foot round, 3 prong extention cord. I cut the extension cord long enough to push the male (the part that plugs into the wall) up into the wall box, then pushed the remaing cable up the second channel guide into the wall box, connected the two white wires together and used appropriately sized twist caps. Connected the thermostat wires to each individual black extension cord wires. Thermostat is not polarized. Mount the thermostat to the wall box. Plug the extension cord from one of the cable guides into the wall outlet, the socket end of the extension cord is for the room heater male plug. Turn the heater switch(s) to high, heat knob to max.Many oil filled heaters cannot reject enough heat on high without overheating the unit! So manufacturers put overheat cutoffs to cycle the element off until it cools. JUST GREAT! This derates the heater from 5200 btu's to about 3000, maybe. That 1500 watt heater is really 800/900 watts. The specs. are on paper only. Solution: A 7 inch metal cage, fully rotatable 3 speed table fan. 1 programable timer. Place the fan on a side of the heater, angle it up towards the upper portion of the oil filled heater. Plug the fan into the timer, the timer into another wall outlet. Match the timer schedule to the thermostats schedule. The heater can now output all its heat indefinately. One on/off cycle should be adequate. Clean the fan on a regular basis. DO NOT CONNECT ALL FOUR BLACK WIRES TOGETHER AS ONE BIG TWISTED CONNECTION.Reader assumes ALL liabilities! How I did mine, and posting on Amazon reviews, is not to be taken as an instruction or direction on how to install, wire, or use this product with an electric heater. If you are not well versed in electrical theory and application, consult someone who is.