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I have power to the primary control, but my furnace will not fire up what can it be?

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Furnace wont keep kicking back on. On its own, led light does blink 3 times stops and blinks 3x again

Without knowing fuel or model, it could be bad relay in primary control or loose wiring, on either power or t-stat side.

*I never recommend homeowner attempt to repair/replace any parts on heating appliance. Any information is strictly to educate homeowner on functionality. Always contact a heating professional for service and annual tune-up.

Feb 13, 2016 | Heating & Cooling

1 Answer

Furnace wont always turn on

make sure u have a new fiering nozzel it need to be changed every year, if good check and clean you cad cell, if still problems replace oil primary

Dec 23, 2015 | Heating & Cooling

1 Answer

Honeywell R7184 P 1098 no lights on

not sure how this question got in the fountains and ponds section unless you use a oil fired heater to heat your pond/ pool ?

but that part number comes back to a oil fired burner primary controller , if it has no lights on it one of these solutions is correct (1) no power to controller
(2) controller has no faults and is ready to operate,standby (3) primary controller is defective

as far as I know there is no Power on light 4 this model so it wont even tell you its got power applied to it , you will have to use an alternate means to verify power is applied to it

May 14, 2015 | Garden

1 Answer

Need wire diagram from the hot wires feeding a blue angel oil burner and blower motor

What kind of primary control? Beckett?Honeywell? Carlin? Control model #?

Oct 18, 2013 | Peerless WV-DV-04, Oil Fired, Hot Water...

1 Answer

Comfortmaker furnace model GUH075 requires resetting for flame to light?

Is this an oil or gas fueled furnace? All heating appliances have several safety switches in the controls. Flicking the on/off switch (assuming you mean the emergency toggle switch) is not resetting the burner. If you pressed a button near the red light,that MAY have been the primary control reset.
Your problem could be anything from the main power switch to one of the many controls with a wiring or sensor issue. Or even a t-stat wire problem.
Regardless, a thorough technician should be checking the entire circuit, from the t-stat to every control in the circuit. Including every wire.
Lastly, a qualified licensed technician should never diagnose without being in front of the appliance. Hope this helped :)

Jan 30, 2013 | Heating & Cooling

1 Answer

Out thermosat for our furnace and air conditioners will not work. There is no poweer going tot he thermostat at all.

Hi, if you have no power to the stat, go to the furnace if this is a split system. Depending on the year you have, this unit may have the main circuit board with a 3 to 5 amp control fuse plugged into it. If this is what you have, check this fuse, it is the same as the fuses in your car. If you don't have this circuit board, locate the transformer where your thermostat wires come in and check for power at both the 120 volt primary side ( power in ) and see if you have 24 volts coming out of the secondary side of it. If no power in, check the circuit breaker to the furnace. If there is power in and nothing out, the transformer is gone. Check close for any breaks in the stat wires at the furnace also. I may need to have the model and serial numbers, and if its a split gas fired or a heat-pump unit if this information does not apply to your unit. Let me know.
A/C, & Heating Contractor.

Mar 11, 2011 | Coleman Heating & Cooling

1 Answer

Burners not firing & LED flashing 4 times

Translate four LED flashes to mean your furnace has a primary limit circuit open, possibly from loose wiring or blocked filters. Check and clean filters, tighten wiring and check the flue for blockages.
A typical limit looks like this: themobilian_1380.jpgConsult your furnace schematic to determine how many of these puppy's are wired in and around the furnace. Make sure they all have continuity. Have the power OFF before you reset the limit. Ouch!

Somewhere in your furnace all of these flashes have a chart you can consult usually located on the backside of the blower cover.

Feb 10, 2011 | Goodman Heating & Cooling

1 Answer

Why two 24 Vac on aprilaire 700's control unit?

Okay, I looked up the installation manual online to see exactly what you are working with.
Yes the R anc C need to be hooked to the transformer supplied with the unit. The primary 120v side needs to be hooked into the power coming into the furnace. this can easily be done were the L and N get hooked into your furnace or circuit board on the furnace. This will provide the contiuous power to the unit. Preferably you will hook this after the door switch of the furnace so that you will kill the power toit if you take the blower door off.
The ODT terminals are for the outdoor sensor if you want to hook that up it will vary the humidiy in your home according to the outdoor temperature then.
Now the W/G and Cf terminals. If you have 24v coming from the HUM terminals of your furnace you DO NOT need a second transformer. You must check your furnace manual or check the voltage to them with the furnace blower energized. The HUM terminals will only have power to them when the blower should be running.
If the HUM terminals are 120v then you need to get another transformer and hook up the primary side to the HUM terminals so it is powered only when the the blower is running. Hook the secondary side to the W/G and Cf terminals.
So bottom line is that you need to figure out what voltage your furnace is giving to the HUM terminals and then go from there. Some times the EAC terminals or the ACC terminals will be 24v on the furnace board. Either of them could be used also, as they are only energized when the blower is running also.


Jan 25, 2010 | Aprilaire 700 Humidifier

1 Answer

A carrier furnace

check the relay
the primary should have a low resistance
there should be a distinct click when 24 volts is applied to the primary
the secondary should be conductive when the primary is energized (contactors can corrode)
not a solution something to check

Oct 02, 2008 | Heating & Cooling

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