Anybody had any luck with cheap temp controllers?

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warno

Minister of Fire
Jan 3, 2015
1,237
illinois
I'm thinking about getting some temp sensors to add into my system for easier reference. I've been looking at the cheap China made sensors on ebay. I was just wondering if anyone has used these and had any luck with them?

Here's a link to the one I was looking at

(broken link removed to http://m.ebay.com/itm/Digital-Temperature-Controller-110V-Thermostat-Control-NTC-Sensor-ITC-1000F-/381475169381?nav=SEARCH)

Any help would be great, thank you.
 
I have been using BBQ sensors Redicheck I think..for three years now trouble free. I have the Feed and Return pipes coming out the back of the Greenwood insulated, I tucked and taped the sensor under the pipe insulation sitting directly on each pipe. The readout is wireless so wherever I am I carry it and easily monitor the Feed and Return temps..
 
What are you looking to do? If you want to control something then this is the one I used one on my Drolet Tundra wood furnace ...I have about $25 in everything. See it here...
https://www.hearth.com/talk/posts/1995179/
This is the one I used. (broken link removed to http://www.ebay.com/itm/New-Digital-PID-Temperature-Controller-Control-RNR-1-Alarm-Relay-Output-TC-RTD-/401039444273?hash=item5d5fd04931:m:mtByIhcdh_MNe4yLNBcBoaQ) (it was $13.98 delivered when I bought it)
and a thermocouple for $6.99 delivered...and a 24vac relay because both of the contacts were NO, and I needed one NO and one NC contact
 
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If you are looking to just monitor temps then I have had good luck with a Maverick ET 732 wireless BBQ monitor. ($49 on Amazon right now) It is good for ~300' of range, can monitor 2 different things, (I monitor stack and supply plenum temps) has low and high alarms, the batterys will last a little more than 1 heating season, works great.
 
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This is actually for next year's project, but I'm wanting a temp reading for the following:

Temperature controller for pump on/off to resupply storage tanks from boiler
Temperature readout of supply and return line from house load
 
Sounds like you need one of each. The Maverick will give you the remote temp reading on the lines and the controller will run the pump and give you a local temp reading
 
Do the ones from China work ok though? I'm looking to go cheap on temp reading where possible. But yet I still hate to have to replace something that goes bad often, since that defeats the cheap idea pretty quick.
 
I can only speak for mine but both the controller and the monitor are working fine. I actually bought 2 of the controllers, 1 for me and 1 for my sister who has the almost identical setup to me. Well, actually I only actually bought one, I ordered 1 and when I got it one of digital segments was out (I still used it, you can see it in my pic in the link I posted, the bottom of the center zero is out on the green readout) When I contacted the company about it they sent me a new one and told me to just keep the old one. The new one had no issues at all and honestly the 1st one actually works OK
 
I've got a bunch, that look like this:

http://www.ebay.com/itm/0-56-F-C-12...em3f1bbf3b1f:g:gooAAOSw0JpV5COx#ht_3636wt_680

Had them 3 years or so now. They've been on pretty well constant the whole time. I notice a couple now will show wonky numbers once in a while - will display 185 out of the blue. Then later go back to normal. I've got 4 mounted in a metal electrical box that show all my DHW related temps. Have another box half finished to mount 4 more, but for now have just one zip tied up that shows my tank temps. The ones I have take two probes, and alternate back & forth between the two. So they show two temps. Think the one I linked only takes one probe. You'll need a 12v wall wart to get 12v power - I had one kicking around for something that had quit working. sure-audio was the Ebay seller I got mine from, very good transaction.

I also have a Maverick like mentioned above, got it a year ago. It works good - I can see my top & bottom tank temps when I'm lying on the couch. Or wherever else I want to sit the display. Both types are very consistent in their displays so would say are both quite accurate. The Maverick takes batteries though - had to replace them when I started burning this fall.
 
I've got a bunch, that look like this:

http://www.ebay.com/itm/0-56-F-C-12...em3f1bbf3b1f:g:gooAAOSw0JpV5COx#ht_3636wt_680

Had them 3 years or so now. They've been on pretty well constant the whole time. I notice a couple now will show wonky numbers once in a while - will display 185 out of the blue. Then later go back to normal. I've got 4 mounted in a metal electrical box that show all my DHW related temps. Have another box half finished to mount 4 more, but for now have just one zip tied up that shows my tank temps. The ones I have take two probes, and alternate back & forth between the two. So they show two temps. Think the one I linked only takes one probe. You'll need a 12v wall wart to get 12v power - I had one kicking around for something that had quit working. sure-audio was the Ebay seller I got mine from, very good transaction.

I also have a Maverick like mentioned above, got it a year ago. It works good - I can see my top & bottom tank temps when I'm lying on the couch. Or wherever else I want to sit the display. Both types are very consistent in their displays so would say are both quite accurate. The Maverick takes batteries though - had to replace them when I started burning this fall.


Those from EBay, do you just submerge the lead into the tank? If yes would you just hang them in the tank at different levels..and how long are the leads. TY
 
I've used a cheap Chinese thermocouple controller ($35 on eBay) as a on-boiler combustion temperature gauge. Worked OK for two years, then died. I'll echo Maple about not submerging the sensor. I tape them oun the outside of pipes with insulation, and in my storage tank I made a 4' deep sensor well out of soft copper. Hot water for long periods is death to plastic.
 
I use two PID controllers like in post #3. One controls the pump from boiler to storage. The other controls the boiler fan.

The original boiler switch that controlled the fan died and is no longer made. The PID controller handles that fine.

If you want to control your pump, get the ebay package that has a SSR and you decide if you want a lower temp sensor or a high temp sensor. I have the K type high temp sensors in the flame path. The lower temp sensors could be strapped to a water pipe.

There is a lot of flexibility on controlling a device with the PID, like your pump.

I think they are a little pricey for just temp monitoring.

I kinda like that BBQ sensor.
 
For monitoring only I've used DS18b20 digital temperature sensors to LED panel meters for temps less than 225F and K-type sensors to monitor flue temp to similar meters designed for K-type sensors. These have been in use for several years, about 35 in total on four different monitoring panels. I think only 1 or maybe 2 have failed, and during the heating season they are "on" 24/7. Power is from a walwart DC supply.

A benefit of using DS18b20 sensors is that they can be wired together to share the same cable, although I tend to use several cables anyway because of convenience due to location of the sensors.

Pix of two of the monitoring panels.
[Hearth.com] Anybody had any luck with cheap temp controllers? [Hearth.com] Anybody had any luck with cheap temp controllers?
 
I too have used the inexpensive Chinese thermocouples controller from eBay. One is on my Tarm (K-type sensor) with a probe in the flue and serves as a high limit control which shuts the draft fan "off" if flue temp is higher than 250C (482F), and then turns the draft fan to "on" when the temp drops again. It uses the internal relay, and it has been in operation for several years. It has "saved" me twice when I inadvertently failed to shut the bypass damper after reloading wood into the Tarm.

The other, which uses the internal relay to control a 240V power relay, turns off the draft fan on a Wood Gun E500 on a fire-out condition, with a push button electric manual re-set to turn the fan back on when starting a new fire. It too uses a K-type probe in the flue. This one is in its 2nd year of operation. I also wired it to allow fully manual operation if the controller should fail for any reason.
 
A benefit of using DS18b20 sensors is that they can be wired together to share the same cable ...
Correction: this works for my digital data logging controller but not for the LED meters. Each meter needs a separate cable.
 
Those (in post 14) look like the same ones I have. Last time I bought, almost exactly 3 years ago, the temp meters were $7.50 each and came with one probe, and extra probes (3m. of wire) were $6.99. Mine each take two probes & alternate between them on the display.
 
Maple1 was right on. I only have one meter that alternates between the two sensors, one for outside and the other for inside temp. The big display panel box I got off eBay, I think about $50.00 + shipping, and I cut the openings for all the meters myself. The lettering is the peal-off stuff from an office supply store. The small panel was a salvage piece, again cut the openings, and then painted the front to match the color of the Froling it serves.
 
I too use the cheap controllers. I'm using them on my boiler and I'm also using for controlling a plating line. I know enough people have chimed in, but I wanted to put this out there in case.

Timbo-0012 is a really good guy to buy from if you like what he is selling. He tests everything to help ensure they are not duds coming from china. I know that in itself is a bad sign, but its a problem with all the cheap controllers IMO. Tim will spend time with you helping you get exactly what you need including some of the smaller wires etc and making sure you know what to do.

(broken link removed to http://www.ebay.com/itm/DIGITAL-PID-TEMP-CONTROLLER-F-C-25AMP-SSR-WITH-HEATSINK-AND-PT-100-PROBE-/261286976034?hash=item3cd5eada22:g:p9kAAOSw-jhUClPU)
 
Thank you. I'm really liking the PID controller functions I think I'll be getting one of those. When the time comes.

Thanks everyone for the info. If anyone else has any input at all, by all means let me hear it.
 
I'd like some cost-effective sensors too. Back in 2009 I used about 30 x 1-wire sensors (probably the same as/predecessors to the ones discussed here), wires on little PCBs we had printed and soldered ourselves (with a pull-up resistor I think) and then a couple of connectors so we could daisy-chain cable them with CAT5 on a bus layout. It worked well, but the whole thing was very "string and chewing gum" and I got the distinct impression that trying to get the serial port side to work with Windows (my skill - I'm a Microsoft SQL database programmer) was not the way it was ever designed / tested, and every time I, personally, brush up against anything with a Unix flavour I spend days scratching my head / figuring things out, and I do not have that time available for that purpose. So, for me, it has got to be (reasonably) plug-and-play with Windows and not too "boy's own"

I also need some sensors to be remote (e.g. temperature of my greenhouse, I don't have any CAT5 to it, and its a fair way from the house), and I need some (again: remote) water level sensors for both my rain water harvesting and also the outfall tank from my foul water digester (we are not on mains sewer drainage, but we do have mains water)

Background:

I have above-ground rain water harvesting tank, and what was the original sceptic tank now collects all rainwater from roof etc. That contains a pump to fill the above ground tank, I could do with some sort of control over how urgently I need to fill the above-ground tank. In summer I want to collect 100% of anything! In Winter if varies a bit, depending on whether the tank is already full, and how wet/dry the winter is.

The new foul water digester (which replaced the older sceptic tank) outputs to an open-bottomed vertical tank (as a soak-away). In practice we are on heavy clay, so it doesn't soak away very fast. In Winter I don't need the water, so am happy for whatever will soak away to do so, and would thus like to run the "pump on" level close to full, and set the pipes so that the water is pumped to waste in the nearby ditch. In Summer I can change the plumbing so that it goes into nearest rainwater drain, and thus back to old sceptic tank in order to supplement any collected rainfall, if the storage tanks are getting low. But ... my potable mains water is "hard" and my plants prefer "soft" / rainwater, so I try not to re-use my water unless the weather is very dry.

I also want alarms. Currently we have a submersible pump with a float-switch. That float, from time to time, gets stuck (either on or off) with the risk of either overflow back into the treatment chamber, or pump on continuously with no water to pump. I could easily sort that out in software, with alarms, if I could only "log" what was going on ...

Happy to start a new thread if this is taking the original conversion to far off-field! My requirement is more for "logging" than for "display panel".
 
Sounds like we should talk - we need a support group for this. I started out with cheap sensors and relay logic and told myself I could stop any time. It wasn't true. It's a slippery slope - temperature sensor here, LED status there, pretty soon you're embarrassing your wife at parties by talking animatedly about latent heat and stoichiometry. I eventually ended up with this:

[Hearth.com] Anybody had any luck with cheap temp controllers?

With the help of a good wife and understanding friends, I've been able to lead an almost productive life, but it's a never-ending struggle.
 
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Sounds like we should talk - we need a support group for this. I started out with cheap sensors and relay logic

I graduated from that, and we now have some professionally installed stuff. The Lighting (Lutron) and Alarm stuff is excellent, CCTV is cheap-Chinese and "passable" (finding a clip is not possible based on, say, "something changed in this area of the field, and "review at 4x speed" isn't anything like 4x ...). The heating stuff is dreadful - little better than the old turn-a-dial thermostats at its best, and at its worst absolutely terrible (parasitic heat usage from midnight to 5am most, but not all, nights that took months to properly diagnose and cure (frost-safety mode even though internal temperature was 5-10C above the frost setting ...), and, on a thermal store / wood-batch boiler basis, parasitic / unexpected / unexplained heat usage is a major disaster as there is then not enough for anticipatable usage - whereas with oil its only money that you are burning!!)

told myself I could stop any time. It wasn't true. It's a slippery slope - temperature sensor here, LED status there

managed to avoid that addiction ... bought books on Electronics, told myself I could learn it, in fact I had done some electronics at skool ... but luckily the books I bought were heavy-end, and not a light read, so I didn't get enough knowledge to get hooked :) but spent a lot of money on professionally installed systems instead ... so not all good!

pretty soon you're embarrassing your wife at parties by talking animatedly about latent heat and stoichiometry

I get very few invitations to dinner any more ... I spend far too long telling my rich-*astard mates that whilst I am happy to concede they need a Range Rover to drive across a ploughed field, I tell them they don't need it to take the kids on the school run - just on the off chance that there might be a ploughed field on the way! - and that they can easily afford another, Eco, car for that purpose.

But ... that said ... we moved wholesale from poor fuel economy sports cars to small Eco vehicles, settled on Volkswagen (of which we have 3) and look where that got us? :( I will never, ever, buy a vehicle from / trust VW, or any of their associated companies, again). I probably should have looked more closely at battery-powered vehicles last time we changed, I thought they weren't ready for prime-time, but that's going to be my next-time solution.

I eventually ended up with this:

Mine is a bit smarter - just as well given what it cost! Can only find photos during construction though ... I'll take new ones and upload later.
 

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