[SOLVED] robert shaw thermostat says 'lo bat' but battery is fresh

I tried replacing the batteries twice. The first time the thermostat worked fine for a couple hours but after that it shuts off and says 'lo bat'. I referred to the users manual and got nothing.

Thanks, people.

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Reply to
sofireme
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Are you using the right cells (batteries). Rechargeables often develop less voltage. If so, the thermostat is defective.

Reply to
Charles Schuler

Are the contacts clean in the thermostat? Where the batteries go, that is. Clean them with a pencil eraser. Have you checked the batteries on a meter?

Reply to
Bob M.

In my furnace, if the safety decides to disconnect it stops juice to the thermostat which then runs down the back up battery and end up with drained battery. Usually happens if condensation pump sticks and overflow tells furnace to turn off. If you have a condensation pump check the sump to see if it is full. Otherwise you may have a more significant furnace problem. Condensation pump floats often stick due to algae and sump needs to be cleaned once in a while.

Reply to
Art

Hi, When lo battery is indicated it has few more days juice left to function. Use good Alkaline ones. If it keeps doing that maybe something wrong with the 'stat; like cracked solder joint/PCB trace, etc.

Reply to
Tony Hwang

Hard to believe that you allow the condensate pump to shut down your furnace. What's the better option---some water on the floor or frozen pipes? Do you actually spend time away in the winter unconcerned that a "sticky" float could trigger frozen pipes? MLD

Reply to
MLD

The issue is condensate backing up into the furnace. I didn't design it.... talk to industry leaders. My house has 3 separate HVAC systems. The only way my house could freeze is a power failure.

Reply to
Art

Had same problem with same stat. This worked for me. Pull cover. heat/off/cool switch to off. Remove batteries. remove red and white wires (which supply 24 volts to the circuit) hit reset button. Wait 20 minutes. restore red and white wires, put in batteries. Hit reset again. Wait 2 minutes and it should work. Basically cut all power for a while and reinstall. Manual apparently states batteries should be replaced with switch in off position but my quess is most people don't read the manual. This looks like a basic software bug. Good luck.

Reply to
RDemarest

If you want to remove external power from the thermostat, it would seem it would be a lot easier to just turn off the AC power to the furnace, instead of removing wires from the thermostat.

Reply to
trader_4

replying to sofireme, robert wrote: I solved the problem by replacing the sole electrolytic capacitor. Works again. original capacitor was 1000 uf 6 volts. I replaced with 1000 uf at 10 volts which is slightly bigger but the 6 volt one would work. I had the part and a soldering iron.

Reply to
robert

replying to sofireme, robert wrote: Find someone with a soldering iron and replace capacitor. Should cost about 30 cents on line. I spent quitr some time on research and ended up buying a new thermostat but did repair my RobertShaw in about two minutes.

Reply to
robert

replying to RDemarest, robert wrote: I wrote the above and thought it worked. No, it was working less than a day. You have to replace the electrolytic capacitor. It is the only component that degrades with time. Mine now works.

Reply to
robert

replying to robert, Douglas wrote: At the risk of sounding foolish, I discovered my thermostat does not like Duracell batteries. Convinced that maybe I just had a bad pack, I opened a new one. Still no good. On a whim, I slipped in another brand that I found loose in a drawer. I have no explanation for this, other than it worked.

Reply to
Douglas

You do not sound foolish, at all!

I've had similar probs with copper-tops. I bought some brand new Duracell AA bats and put 'em in my brand new Maglite. Came out to my van at O dark thirty and turned on my brand new everything flashlight. It was a dark Wintery morning, jes below freezing. The Duracells would not light! Not even faintly.

later that day, I bought brand new Energizers and put them in my Maglite. Very next morning, it was about the same time and temp (dark, jes below freezing) and the flashlight lit up jes fine. I've never bought another Duracell, again.

nb

Reply to
notbob

Are Moaners Hub posts real people?

Reply to
Stormin Mormon

replying to sofireme, James wrote: Try stretching out the negative terminal spring, it fixed mine with the same issue

Reply to
James

Hey, dip shit, the OP had that problem nearly a decade ago. Pay attention!

Reply to
Father Time

replying to sofireme, robert wrote: The only component that "ages" in this thermostat is the electrolytic capacitor. I solder in a new one and mine now works perfectly. I realize this is not an option for most users, but it works.

Reply to
robert

replying to RDemarest, Diann Sanderson wrote: Thank you and God Bless. I followed your instructions and everything started with out having to wait the 2 minutes. Thank you again !

Reply to
Diann Sanderson

replying to sofireme, MainframeSysop wrote: Not sure if this will help, but I have a TX1500uc / TX1500 Thermostat and the BATT LOW would not go away after placing fresh new batteries in the device. I took the batteries out, pressed and held the front buttons, pressed the RESET button inside the unit, even swapped the Elec/Gas jumper temporarily. Put everything back the way it was and popped the unit back on the wall and it was good.

Reply to
MainframeSysop

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