Coleman Presidential II relay issue

[castleromeo]

Hello,
I have a Coleman Presidential II gas furnace/HVAC and recently the reversing relay has been acting up. Unfortunately, relay #7670-308 is no longer manufactured. I purchased replacement relay #7670-3071 and since I installed it, the AC will not shut off like it's supposed to.

NEED HELP!!!

Thanx.

[HayZee518]

reversing relay

do you have a schematic of how the relay is connected in the circuit?
I looked at the picture and it's pretty straight forward. two coil terminals and two control terminals.
My only thoughts are what is the switch make-up? normally open or normally closed.
when it's energized, what do the contacts do - open or close?

[castleromeo]

do you have a schematic of how the relay is connected in the circuit?
I looked at the picture and it's pretty straight forward. two coil terminals and two control terminals.
My only thoughts are what is the switch make-up? normally open or normally closed.
when it's energized, what do the contacts do - open or close?

The original sequencer is a normally open type switch. My multimeter shows a current flow across both sets of terminals which is the opposite of what I need. However, all the catalogs list this sequencer relay as a direct replacement for the old one.

[castleromeo]

HERE are some pics of what I'm referring to.

[HayZee518]

sequencer

diagram shows normally closed with power off. if yours is open ya got the wrong relay.

[castleromeo]

diagram shows normally closed with power off. if yours is open ya got the wrong relay.

When I set my multimeter to Ohms and check both sets of terminals on the sequencer, I get a current. This means that it's a normally closed relay. As for the other relay, I purchased a direct replacement for it. I still can't figure this thing out.

[HayZee518]

relay - sequencer

ok, I printed up the diagram so I can see where the wires go to, come from.....
one coil terminal has a yellow wire, an orange and one side of a resistor.
other side has a black and the other side of the resistor. terminal 3 of a switch
the orange of the first terminal goes to one side of the other relay coil.
THAT other side of the coil goes to the first terminal of the terminal board [yellow]
another yellow off the first terminal of the terminal board goes to one side of the n.c. sequencer contact [also yellow]
other side of the contact [orange] goes to terminal 4 of the switch.
switch terminal 6 has no connection. terminal 1 [orange] goes to a multi pole plug.
switch terminal 2 is white and goes to terminal 2 of the terminal board.
switch terminal 5 red goes to terminal 3 of the terminal board.
on terminal board, #2 & #3 go to the thermostat.

[HayZee518]

old relay

take the old relay and read across the contacts and see what reading you get.
compare the readings you get across the new relay coil and the old relay coil.
terminals are marked m & m.
the resistor across the coil - its function is a voltage divider network and gives the relay a sort of time delay pulling in, instead of a snap action.

[castleromeo]

Everything is wired accordingly. I believe that my HVAC uses a normally-open sequencer relay so the part(s) I ordered are NOT a direct replacement. Unfortunately, They do not make that part anymore and the part I have was damaged during removal. IU wanted to replace it anyways because the reed switch inside of the sequencer was sticking thus, the outdoor condenser was still running even though the main unit had cycled off.

I have my eyes set on an old-fashioned 24v Octal-Socket relay that should fix the issue.

[HayZee518]

relay

I was thinking the same thing. they make an "ice-cube" relay that you can pick the contact arrangement that suits your application.
a potter-brumfield or omron octal base relay will also work.
get one rated at 24 volts for the operating voltage. coil terminals are 2 & 7.
contact arrangement terminals are 1 - 3 - 5
one is common, the other two are either normally open or normally closed with no control voltage applied.
the contacts swap when a control voltage is applied.
save the resistor or remove it completely when using this type of relay.