Question about Honeywell Electronic Programmable Heat/Cool Thermostat - CT3300A100 Heater

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Thermostat problem We recently installed a new thermostat. The heat does not come on now. We suspect that a wire is broken in the wall leading to the furnace. How do you replace the wire for that zone.

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Buy some more thermostat cable with the same number of conductors inside it that you need. Twist the wires in the wall to the conductors on the new cable you just bought. Wrap the connections with electrical tape and pull the new cable with the old cable, starting at the furnace. You will then have all brand new conductors to fit to your new thermostat.

Posted on Jan 12, 2009

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One of the thermastat wires attaching to the williams heating on the wall became loose from the screw and didn't seem to be making little of no solid contact like a car battery might due. i tightened the...

If it touched a grounded metal surface, it is possible, leave the wires hooked up at the furnace, pull the thermostat off of the wall, disconnect the 2 thermostat wires, and then twist them together, the furnace should fire, if it does, then the thermostat is shot. Replace the thermostat, usually when there is a short, it burns out the heat anticipator on the thermostat.
Good Luck,
Paul Gibson

Apr 03, 2010 | Williams 1403622 Gas Compact Heater


Thermostat Problems - How to Change the Thermostat for Heating or Cooling

You have a thermostat problem or you want one of those fancy new digital programmable thermostats and wonder if you can replace it yourself or if you need to have the HVAC Guy come and do it for you. The good news is that it really is not all that hard. With a bit of guidance you can easily do the job yourself. Here are some pointers that will help you to get the job done.

One of the most important things that you need to do is to make sure that you get the right thermostat for the system that you have. Find out what voltage your system is before you got to get a thermostat. Also know whether your system is a heat only or a heating and air conditioning system. If your system is a heat pump system then you need to know that also. Hybrid systems that use both the heat pump and a fossil fuel heater are much harder but that can be handled if you know it up front and plan accordingly.

Taking note of all of this information you can now go shopping for you new thermostat.
There are many choices to chose from and you usually will want to be in the mid price range. That will get you a good quality thermostat for a great price. If you are vision impaired you may want to look for a digital unit that has a back light. These make seeing the numbers much easier.

Once you find the thermostat that you want make sure to read all of the instructions that come with it. Reading these instructions will save you a lot of time and make your life a lot easier. Mark all the wires with the letter of the terminal that you removed the wire from. You will reinstall the wire under the same letter terminal on the new thermostat.
However before you remove any of the wires make sure that you turn off the power to your heating unit or air conditioner first. If you have both then it would be a good idea to kill the power to both to make sure you have the low voltage all dead. The wires to the thermostat are 24V AC usually and that will not hurt you but you could burn up a transformer if you are not careful.

Carefully remove and mark all the wires, and remove the old thermostat. Securely fasten the new thermostat to the wall and reconnect the wires to the new thermostat, if you are installing a programmable thermostat you may want to pre-program it before placing it on the wall. By inserting the batteries into the thermostat most of them will let you program them in your hands rather then trying to look at it on the wall.

That’s really all there is to changing your thermostat. If you can follow some simple instructions telling you how to read some letters and match wires than you can change your own thermostat.

on Dec 06, 2009 | Heating & Cooling

1 Answer

How do you install a 2 wire heat only honeywell thermostat?

TURN THE POWER OFF. You need to be sure that the thermostat is made for the control voltage of your furnace. If the new thermostat has mercury contacts it has to be level to be accurate. One wire would be connected to the R terminal of the thermostat sub base and the other wire would be connected to the W terminal on the thermostat sub base. Seal up the hole in the wall where the wires pull through so cold air does not effect the thermostat. If the thermostat has an adjustable heat anticipator you will need to check the amp draw through the thermostat to set the anticipator properly. If you do not have an amp meter I would start out at a .4 amp setting and see how the thermostat cycles.

Nov 24, 2009 | Honeywell CT87B ROUND HEATING&COOLING...

1 Answer

Rewire an old 2 wire thermostat to a honeywell 5-1-1 programmable

I connected the blue wire to the R and the white wire to the W on the old thermostat and shoved the new Honeywell 5-1-1 Day programmable thermostat up the first guys *** that i ran into at Canadian Tire

Thanks for your help

Dec 28, 2008 | Honeywell Electronic Programmable...

2 Answers

Thermostat Wiring: W2? E? Where to connect?

You have a heat pump. You need a thermostat for "Heat pump with Electric back-up heat". Make sure the 'stat has either an "aux" (auxilliary heat) or an "E"(Emergency heat) terminal. The wiring instructions will be provided with the thermostat.

Dec 15, 2008 | Honeywell Electronic Programmable...

1 Answer

Wall heater does not work

Hello drfixsit,
I can only make assumptions on your setup based on your description. I am assuming you are referring to a gas wall heater that has an electronic ignitor and that you shorted the thermostat wire leads together to simulate 'calling for heat' .. If that's correct, then here's a few things you can try.. If you can open the wall heater access panel to see where the burner is, you should see some kind of igniter there too.. Rather than short the wires at the thermostat, why not ,...make a wire jumper at the heater itself and short across the contacts of where that thermostat would plug in? By doing that, you take the wiring out of the equation.. A short across the thermostat terminals at the heater should turn th eheater on and call for heat.. If everythings working, you should get gas into the burner and the ignitor should provide a spark to get a flame established.. I hope I helped you.. if not.. please elaborate on whats actually happening or where I am wrong..

Nov 29, 2008 | Heating & Cooling

1 Answer

Frequent cycle times on my home furnace

There are a few things that can cause this problem. The most common is the hole behind the thermostat for the wiring was not covered up when the thermostat was installed. The thermostat will sense the air in the wall space or the basement if it is open to the back of the wall supporting the thermostat. Turn off the power to the air conditioner if attached and the furnace, remove the thermostat from the wall and seal up the wiring hole with duct tape. Insure the thermostat is mounted level when reinstalled. The thermostat should be mounted to sense the return air to the furnace, if the stair well leads upstairs, warm air rises, so keep the upstairs close to the same temperature as down stairs or move the thermostat and install a door to block air movement to the upstairs. There is a heat anticipator on the thermostat, the setting for it is in the installation manuel. For most gas furnaces it is .8. It is very easy to short out the thermostat when making this adjustment, so always have the power off.

Nov 26, 2008 | Honeywell Electronic Programmable...

1 Answer

Replacing Round Honewell Mercury Thermostat

try to get one that is made for oil heat, the installation is easy only two wires, and the instructions make it easy.

Oct 23, 2008 | Honeywell Electronic Programmable...

2 Answers

Wiring on thermostat tl7235a1003

OK, here's my guess at this...I hope someone more knowledgable will confirm or correct me.

A line voltage thermostat switches the power to the baseboard heater. In other words, it's just like a wall light switch except it activates and deactivates based on the temperature.

I think your old model CT62 was wired exactly like a light switch. The hot wire to the light is broken then run to the wall switch and then back to the light so there's no neutral wire at a light switch box. This worked fine for your CT62 because it did not need power, it only needed to switch it.

The new model TL7235A1003 requires electrical power because it's programmable so you need both a hot wire and neutral wire at it's installed location. In addition you also need 2 wires leading to the baseboard heater so the thermostat can supply it's power.

I believe L1-L2 are to be connected to the hot/neutral wires, and the Load wires go to the baseboard heater.

If I am correct you will not be able to use this thermostat without some re-wiring.

Good luck.

Nov 27, 2007 | Ingram GMS90904CXA Heater

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