Robertshaw gas valve wiring help

[knied1]

I have a Reznor heater that im installing.
I bought it used, and it did not come with a manual.

it has a Robershaw 7000 BR gas valve on it that has been converterted to propane, and im looking to wire up the gas valve

on the gas valve there are three terminals
one labeled TH, one labeled TR, and one in the middle labeled THTR.

I know these are thermostat connections, but am not sure of their connections.

any help would be great

Thanks

 

[Rookie2]

 

[knied1]

Rookie2....THANKS

I attached Pic of the unit I bought.
in pic 1 you will see the gas valve.
there is a combined 2 wire cable that is cut off...it looks to be what should connect to the wall mounted thermostat. the red wire is connected to the gas valve, and yellow one is connected to the blue thermostat wire on the voltage regulator.
the brown wire goes to the voltage regulator. and the black wire is not connected to anything, cut off about 12 inches from the gas valve.

So the red and yellow from the 2 wire combined cable goes to the wall mounted thermostat.
but
where does the black wire go to?

Thanks again

 

[LS6 Tommy]

Voltage regulator??

Tommy

 

[FMC]

piano wires all you need lol(sorry couldnt help myself)

 

[lilredex]

Need to move on to the next vid......about 2:20 on here:

Essentialy, the thermostat and the high limit switch are wired in series, and he shows you the connections.

 

[knied1]

Voltage regulator??

Tommy

According to the wiring diagram on the side of the unit yes its a voltage regulator....makes sense because it needs to go from 110v down to 24v, and is mounted to the fan motor, but im sure on other units its located other places

 

[knied1]

piano wires all you need lol(sorry couldnt help myself)

anything to get your post count up I guess

 

[knied1]

Need to move on to the next vid......about 2:20 on here:

Essentialy, the thermostat and the high limit switch are wired in series, and he shows you the connections.

this unit is like 25 years old, and I don't see a High limit switch, and nothing on the wiring diagram for I high limit switch either.

im assuming the wire does nothing then, and not really sure why he had it on there.

BTW THX FOR THE LINK

 

[knied1]

Ill see what I can figure out.....weird how the wiring diagram only says " gas valve connections" and nothing else.....the diagram shows everything else including the wiring inside the motor, but nothing for the gas valve.

Not looking to use the unit on a daily basis, just 5 or 6 times a year, and not even have the pilot lit when not in use since it will be used on a 100# propane tank.

THX AGAIN

 

[knied1]

Looked at the unit again, and can not see anywhere it should be wired to.......
is there a picture I can take where someone is able to simply say connect the black wire there?

Thanks

 

[knied1]

After digging around the unit more, I found this schematic on the back of the access door to the pilot.

looking at this It appears that this unit has only 2 wires to the thermostat from the gas valve, and the thermocouple as the " energy cut off"

The first diagram I found had four sections of "add this to basic" for this and that option....this one appears to be specific to my unit

Would you guys agree with how im reading this one?

Thanks

 

[ctfjr]

Yes that looks like a basic wiring diagram. btw there are 2 terminals on the gas valve that are actually connected to anything. Th and Tr power the gas valve. Th-Tr is just a tie point. Th (thermostat) and Tr (transformer) are the black & brown wires shown in your diagram. You should make sure that you have a high limit on the unit - usually wired in the 115 volt side.

 

[LS6 Tommy]

According to the wiring diagram on the side of the unit yes its a voltage regulator....makes sense because it needs to go from 110v down to 24v, and is mounted to the fan motor, but im sure on other units its located other places

That's what the rest of the planet calls a transformer.
That being the case, your system does not have a power pile as in the video Rookie2 posted. Blue from the transformer goes to the fuse on the diagram. Blue from the fuse goes to R on the thermostat. W on the thermostat goes back to TH on the gas valve. TR on the gas valve goes to Brown on transformer.

Tommy

 

[Rookie2]

That's what the rest of the planet calls a transformer.
That being the case, your system does not have a power pile as in the video Rookie2 posted. Blue from the transformer goes to the fuse on the diagram. Blue from the fuse goes to R on the thermostat. W on the thermostat goes back to TH on the gas valve. TR on the gas valve goes to Brown on transformer.

Tommy

I was off on that,sorry but I always expect people to get the hint that there is more info on you tube. That is an old valve and the wiring diagram doesn't help a bit. There is some interlock/control (two brown wires ) at the thermocouple that need to be wired into the valve. Newer valves have one black wire. Any how He needs to find a similar one to copy or get an older tech to help.

 

[Rookie2]

OK, I talked to my friend HVAC guy today. The two brown wires at the thermocouple input are connected to the high limit or roll out switch (the low voltage generated by the thermocouple hold the valve open). This will stop the gas flow if there is an open circuit from the switch. There is a solenoid inside that is operated with the 24 volts and switched via the thermostat .

 

[LS6 Tommy]

OK, I talked to my friend HVAC guy today. The two brown wires at the thermocouple input are connected to the high limit or roll out switch (the low voltage generated by the thermocouple hold the valve open). This will stop the gas flow if there is an open circuit from the switch. There is a solenoid inside that is operated with the 24 volts and switched via the thermostat .

Good call, Rookie2! I missed that in knied1's photos. A simple rewire is all that is in order. The new gas valve doesn't have the brown wires from the thermocouple. Just rewire so "W" wire coming back from the t-stat goes to one of the wires on the limit switch and the other wire on the limt goes to "TH" on the valve. "TR" goes to Brown on the transformer.

Tommy

 

[knied1]

Rookie2, and LS6 Tommy,
Thanks for the information, I was assuming that the guy I bought the heater from had things wired incorrectly considering how he had the 110 side wired, but as we all know assuming is a very dangerous thing.

BUT.
JUST TO BE CLEAR....you are talking about wiring the limit switch, and according to the wiring schematic the gas valve gets wired to the transformer and the thermostat.

I got called out earlier in the thread for calling the transformer a voltage regulator like stated on the primary wiring diagram......again assuming can be a dangerous thing.


Thanks again

 

[LS6 Tommy]

Rookie2, and LS6 Tommy,
Thanks for the information, I was assuming that the guy I bought the heater from had things wired incorrectly considering how he had the 110 side wired, but as we all know assuming is a very dangerous thing.

BUT.
JUST TO BE CLEAR....you are talking about wiring the limit switch, and according to the wiring schematic the gas valve gets wired to the transformer and the thermostat.

I got called out earlier in the thread for calling the transformer a voltage regulator like stated on the primary wiring diagram......again assuming can be a dangerous thing.


Thanks again

After a second (and more careful) look I see what the design is now. They're killing the 120V feeding the transformer if the limit switch trips. That kills the whole control circuit, but allows the fan to run until the fanstat shuts the fan off. With the old gas valve, the t-couple was probably wired in series with the t-stat and transformer. Newer gas valves just get wired right to the t-stat and transformer.

I wasn't calling you out about the voltage regulator, just asking as I had never heard a transformer referred to that way before.

Tommy

 

[knied1]

Well,

I got everything hooked up and running tonight.
and YEP it was wired wrong....THANKS for the help.....
Guessing the reason I got it for soo cheep is he had it wired wrong, and couldn't get it to work.......should known not to trust what he had when the 110 side had the common wire tied to the ground, and the bare ground wire on common.....yes I know they technically the same, but still not right.

When he took the heater down he just cut the wires instead of removing them....In hindsight I should have just removed everything that was there and simply wired from the schematic and not even look at what he had there.....

Either way

THANKS ALL for going out of your way to look into this for me