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ehinchman 02-27-2008 04:52 PM

New to the board & need furnace advice...
Earlier today the heat kicked off, I noticed the temp in the house dropping, and it never came back on.

I've been searching online for anything that might be able to help which is how I found this board.

I bought a space heater to try to help get me by, but it's not even dark yet and I am already freezing.

I am not experienced at all in this field, I kind of have to DIY as I am not doing well at all financially at the moment. I'm positive that I could not afford to hire a professional.

With the research that I've done so far, this is what I know...

The furnace is really old. It's a Montgomery Ward SRM-54347B. A search for that model number on Google gives zero results. :(

The house is really old. I have a fuse box (not a circuit breaker) and I checked all the fuses and they appear to be fine.

Gas is flowing to the furnace and the pilot is lit.

It has a newer digital thermostat. I replaced the batteries, which did nothing.

The furnace has a switch that is turned to the on position. The switch has no fuse that I can see.

I looked for a reset switch for the blower, but I am not sure where it is, there may be a common place for this, but there is nothing obvious. I reached in, and spun the fan blades and they seem to rotate fine.

I don't really know what else to check.

Any advice is greatly appreciated. I will check back if I can think of any more questions or have an update. At this moment, it is getting hard to type....

biggles 02-27-2008 06:33 PM

that old you should have a standing pilot,when you look in the burner section should be on if not might of went off.this pilot has nothing to do with thw stat or your is a constant LITTLE flame that tells the main gas valve in the furnace that flame is present.the sequence is your stat call for HEAT...the main GAS opens with proof of a PILOT flame...the furnace heaats up and the FAN comes on.this is a typical ON cycle for older furnaces.the OFF cycle is the stat satisfies the MAIN gas goes off...then the fan "removes the heat" off the furnace and the FAN shuts off...the house should be heated at this time till the next cycle(temperature drops below stat setting)...check that pilot and the brass probe in front of it...if you do have it lit it should be hitting that probe(thermal couple).IF NOT and you need to light it.....shut the switch on side of furnace OFF...IN THE BURNER SECTION turn dial on top of the gas valve to PILOT and PUSH DOWN and HOLD DOWN....lite the piot COUNT to 30, and let up on the DIAL ?QUESTION? does it stay lit if YES turn the dial to ON on top of the gas valve.................stand up step away from the furnace and then reach over and turn the furnace switch back ON...CHECK your stat setting should be calling anyway with the house cold,if it is digital you should have HEAT indication on the screen or ICON for heat telling you he stat is calling.make sure your in HEAT mode with fan in AUTO...if you can't light the Pilot after you release the DIAL?from its PILOT need a new THERMAL item,easy to replace,Home Depot or local hardware you can do it yourself.:whistling2:

ehinchman 02-27-2008 06:57 PM

Thanks for the reply. The pilot is lit as I mentioned above. Is it possible that the thermal couple went bad even though the pilot is lit?

biggles 02-27-2008 07:42 PM

if the piot is lit and the gas valve is in the ON position it is doing its job,if it wasn't producing a sub-voltage the pilot would drop out even in the pilot or on position on the main gas.sounds like a generic furnace there,and it was running with newer stat.shut it down on the gas valve check that the cappilart lead out into the gas valve is tight(small ajustable) to check tightness take a dry towel rag and wipe the coulpe brass end it might be weak...,holding the pilot lit ,but not OK'g the main gas on a call for you have FAN ON from the stat run it to verify you have contol voltage down at the furnace.if you don't have AC on the system...forget the fan check

ehinchman 02-27-2008 08:24 PM

I don't think the pilot is burning weak. It's burning bright, like it always does. Nothing about the pilot seems any different than normal. That's why I thought it had to do with the fan. It doesn't turn on when I put the thermostat to the on position. This is why I was checking for blown fuses earlier.

biggles 02-27-2008 09:06 PM

did the fan run previously when you went to FAN ON at the stat...if it did,your fuse panel may be OK,but your control voltage is shot off the transformer or tripped on a reset on the furnace transformer itself.could be a black push button on the top of the TR.without a meter in use can't have it checked.ONLY WAY without a meter pull the stat and with a paper clip jump R to W and see if you get a MINUTE SPARK.... if you get it you have 24Vs then you need a service guy or maybe it will jump the heat to run OR pull the batteries to see if the furnace powers the stat if 24V is in the furnace the stat should light up on the digital side.

ehinchman 02-27-2008 09:19 PM

I never set the fan to "on" before this, it has always been set to "auto". I will look for a black button, but I don't remember seeing any buttons on anything. I will also try jumping the wires for a spark...

biggles 02-27-2008 09:42 PM

if you don't have AC in the house the FAN test is not going to run. ON fan is the AC hook-up side of your system,how many low voltage wires are connected on the subbase of the stat?don't worry if you get a spark R to damage is done just a QUICK techs test your long has the new stat been in use,and does it have multipule time/temp settings..wake...sleep...leave... return...

ehinchman 02-28-2008 08:39 AM

Yeah, there is no AC. The stat only has two wires connected to it. I couldn't find a paper clip, so I just touched the two wires together, and there was no spark. Not that there would be anyway. This is all new to me.

So this is what I've discovered since last night... I removed the cover to something called a Combination Temperature Control CTC. It has a silver dial in it that I turned slightly clockwise and the fan kicked on and it doesn't shut off. But the air that it's blowing is cold.

To answer your question, the new stat is only about a year old. It does have multiple settings for morning, day, night, and weekends. A over ride function for manually adjusting the temp on the fly. And it only runs when the cover is closed and in the "run" position. The batteries are new if I didn't mention that before, and something that I've noticed is that when the temperature in the room passes the temp on the stat signaling it to turn on, you hear a click when it makes the connection.

It seems that the stat is working fine, but that the furnace just isn't listening to it. Or, there is a problem with whatever tells the furnace to fire up. Even though the pilot is lit, theres not much more going on with the fire... Its not getting hot. At least I now know that there doesn't seem to be a problem with the fan, as it has been blowing this entire time, but blowing cold air...

biggles 02-28-2008 04:31 PM

that silver dialed gizmo is what brings the fan on when stat calls...heat exchanger heats ups,and blows the warm air to heat the space.ther should be 2 settings on that one for f FAN ON 160F,and the higher one for HI-LIMIT TRIP 200F...when the furnace lights off that dial will turn as it picks up the heat rising and the fan will come on the hi setting is for if the filter is blocked up or the fan doesn't work it will knock the burner off with no air moving the heat out of the unit to heat the house.NO SPARK on that JUMP TEST your transformer is shot you should of saw a spark.that would of be that click you hear on the new stat(contacts closing).that your not hearing a click now means the control voltage isn't coming up to your sta so you need to concentrate on the transformer...(easy changeout*)24Volts /115Volts 40 VA rating.....cost to you $10-$ changeout* power down furnace pull the old one and install new TR,check Home Depot or near you..either it is blown or fuse is blown within furnace...that CLICK and NO SPARK you stated was the sign there is no control voltage

ehinchman 02-28-2008 04:55 PM

Actually, I tested the transformer today with a volt meter, and it registered a current. Also, that silver dial and the blower are powered with lines running from the transformer, so I don't think it's that. Although, if it's only $15, I might as well replace it anyway.

Someone else suggested that it could be the gas valve has gone bad. I tested that with the volt meter and it didn't show a current. The gas valve is also powered by a line coming from the transformer. If everything else coming from the transformer is showing a current (and functioning), but the gas valve isn't, it seems like that may be the problem. What do you think?

ehinchman 02-28-2008 05:28 PM

biggles, where would I look to find the fuse within the furnace? I noticed that someone at some point left a box of small glass fuses in the basement. I can't imagine what else they would be for, but I've never seen anything on or in the furnace that looks like a fuse... Does the transformer have a fuse inside it? That's about the only place that I have not looked inside yet...

biggles 02-28-2008 06:40 PM

the glass screw in types are strictly for the fuse box in the basement,the one for the TR might actually be on the TR either a SILVER push button or small BLACK rocker switch.its tiny maybe #3 0r #5 stamp on the reset and doubt it is repalceable like your fuses for box fuses almost like a car fuses under the a visual right on the TR for any thing i explained in resetting...don't expect you to have a VOLT meter,but reading the wires right out of the TR would tell..that is where a tech comes in and bills do a up close check out on it and the connnections on the color wires coming out on one side of it thats the 24v side.the other is the black/white PRIMARY side wires that is the 115V feeding the TR to make the SECONDARY 24V side .the terms i am using are typical for a service guy and just to give you an idea what a guy coming in will look at.

ehinchman 02-28-2008 06:51 PM

The fuses I am talking about are small, cylinder shaped & made out of glass with metal ends. They almost look like a fuse for a car, but slightly larger. I am not confusing them with fuses for the fuse box. I know what those are. Oh yeah, I do have a volt meter...

I'm thinking about going ahead and just getting a new thermocouple, transformer, AND gas valve, replacing them all and crossing my fingers..

biggles 02-28-2008 07:28 PM

Sure they might be for the TR might mount on the 24v side.check the secondary with that meter(set on AC VOLTS)right at the the wire nuts off the 2 different color wire side just out of it should show 24Vs with the toogle switch up. verify the 24v first thermal couple is holding the pilot in so it is have to read 24V at the top of the gas valve to say it is not functioning,do one at a time or you will never know what the problem was.

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