Sail switch power

[ChuckS]

Roof AC Zone 1 control board.

I’ve marked the two blue signal wires that send signal down to furance control board

Both wires that lead into furance Must have a wire attached that comes from the roof AC Zone 1 control board .. this is how the In Command sends signal to furance to run or not based on set point and mode selected

[Mark28RYR]

This really is bizarre. Originally when my furnace first started not coming on I automatically thought sail switch. I pulled it apart and sure enough it had some dust wrapped up in it. Cleaned it off and it may of worked some but it still wouldn’t always ignite so I bought a 2 pack off Amazon. Also bought a high limit switch and control board just in case. Changed out sail switch and still had intermittent issues. Then tried the high limit switch. Same thing. Works some and then won’t. Tried the other sail switch. Now I’m using my meter to check the switches and see both sail switches are not working properly, so I put the original back in which does work good according to the meter, and the original high limit switch tests out ok but I had left the new one in for now. I had also gone back and forth with old and new control board. Back to original control board. Fast forward to yesterday where furnace worked all day long until about 6:30 in the evening. Shuts off and won’t restart. Upon starting the furnace I get 12v on the sail and high limit circuit for just a second before it goes to 0v. Today I take the ignitor apart to check that out. Looks good. I decide to reinstall the original high limit switch. As soon as I put it in and try the furnace I get ignition. I bypassed the sail switch and high limit switch with a piece of wire last night and it wouldn’t ignite. Put it all back together and it comes on fine at the moment. So now I’m really scratching my head as the RV sits here warming up….

Note: one time the other day the furnace shut off before it had satisfied the thermostat. Typically it just doesn’t start at all but that once it was running and shut down before it had warmed the room to the set temperature.

[Mark28RYR]

Originally Posted by ChuckS

** And the blower motor never will spin up with the sail switch bypassed.. The Control board looks for an OPEN in the circuit upon initial demand for heat.

Once the board determines the sail switch is OPEN then the blower will get power and run.. then the sail switch circuit is completed when paddle arm moves to complete circuit...

Aha! Now that makes more sense!

[Mark28RYR]

Originally Posted by ChuckS

Roof AC Zone 1 control board.

I’ve marked the two blue signal wires that send signal down to furance control board

Both wires that lead into furance Must have a wire attached that comes from the roof AC Zone 1 control board .. this is how the In Command sends signal to furance to run or not based on set point and mode selected

Even with a In-Command system controlling the HVAC? I could see with a standard wall thermostat that being the case.

[jsb5717]

Mark, can you take some pics of your furnace? Sail Switch, control board, etc.

If the furnace has been working right along, then now it doesn't, your current dilemma doesn't make sense. If any wires are not connected as they should be then how did it run before? Have you made any wiring changes in your troubleshooting? Are you correctly jumping the Sail Switch?

Without really knowing your mechanical abilities I'm just looking at all possibilities. Something doesn't make sense but it's hard to know where. Correctly jumping the Sail Switch shouldn't stop the blower. So good pics of your components might help be be able to see what you're seeing.

[Mark28RYR]

Originally Posted by jsb5717

Mark, can you take some pics of your furnace? Sail Switch, control board, etc.

If the furnace has been working right along, then now it doesn't, your current dilemma doesn't make sense. If any wires are not connected as they should be then how did it run before? Have you made any wiring changes in your troubleshooting? Are you correctly jumping the Sail Switch?

Without really knowing your mechanical abilities I'm just looking at all possibilities. Something doesn't make sense but it's hard to know where. Correctly jumping the Sail Switch shouldn't stop the blower. So good pics of your components might help be be able to see what you're seeing.

Everything is back to original at this time. No wiring changes were made. Just replacing specific parts. What’s the correct way to jump the sail switch?

[LHaven]

Originally Posted by ChuckS

** And the blower motor never will spin up with the sail switch bypassed.. The Control board looks for an OPEN in the circuit upon initial demand for heat.

Once the board determines the sail switch is OPEN then the blower will get power and run.. then the sail switch circuit is completed when paddle arm moves to complete circuit...

(entirely re-edited)

Woops, I finally figured out what you're saying. The sail switch is normally open, and when heat is requested, the board makes sure the switch is first open, then closes after the fan runs. So the correct way to bypass the switch is to short the leads, but only after the fan starts, not before.

[jsb5717]

Originally Posted by Mark28RYR

Everything is back to original at this time. No wiring changes were made. Just replacing specific parts. What’s the correct way to jump the sail switch?

There are a couple ways to do it. It's all about getting good metal-to-metal contact.

Your switch has 2 prongs and they both have blue wires attaches. The most effective way in my opinion is to pull the wires off of the prongs, use another piece of wire, and make good contact from one end of the blue wires to the other. That closes the electrical loop and tells the control board to proceed to the next step, which is opening the gas valve and firing the igniter.

If the furnace is otherwise operating correctly, when you connect those blue wire ends you should hear the click of the gas valve open and then the clicking of the igniter. The furnace should then fire and run normally. If that happens then you know you've got a faulty sail switch.

I'm sorry if I'm over-explaining but I hope the pics below help. Make sure your jumper wire is stripped on both ends and push the exposed wire into the connectors of the blue wires. Maybe this is what you've already done. If not then give this a try and let us know how it goes.

[Mark28RYR]

Originally Posted by Mark28RYR

This really is bizarre. Originally when my furnace first started not coming on I automatically thought sail switch. I pulled it apart and sure enough it had some dust wrapped up in it. Cleaned it off and it may of worked some but it still wouldn’t always ignite so I bought a 2 pack off Amazon. Also bought a high limit switch and control board just in case. Changed out sail switch and still had intermittent issues. Then tried the high limit switch. Same thing. Works some and then won’t. Tried the other sail switch. Now I’m using my meter to check the switches and see both sail switches are not working properly, so I put the original back in which does work good according to the meter, and the original high limit switch tests out ok but I had left the new one in for now. I had also gone back and forth with old and new control board. Back to original control board. Fast forward to yesterday where furnace worked all day long until about 6:30 in the evening. Shuts off and won’t restart. Upon starting the furnace I get 12v on the sail and high limit circuit for just a second before it goes to 0v. Today I take the ignitor apart to check that out. Looks good. I decide to reinstall the original high limit switch. As soon as I put it in and try the furnace I get ignition. I bypassed the sail switch and high limit switch with a piece of wire last night and it wouldn’t ignite. Put it all back together and it comes on fine at the moment. So now I’m really scratching my head as the RV sits here warming up….

Note: one time the other day the furnace shut off before it had satisfied the thermostat. Typically it just doesn’t start at all but that once it was running and shut down before it had warmed the room to the set temperature.

It ran for over an hour to get up to 68 from 41 degrees. 27 degrees here today with real feel of 16. Few minutes later went to start back up and no ignition. Blower ran and turned back off after about 30 seconds.

[Mark28RYR]

Originally Posted by jsb5717

There are a couple ways to do it. It's all about getting good metal-to-metal contact.

Your switch has 2 prongs and they both have blue wires attaches. The most effective way in my opinion is to pull the wires off of the prongs, use another piece of wire, and make good contact from one end of the blue wires to the other. That closes the electrical loop and tells the control board to proceed to the next step, which is opening the gas valve and firing the igniter.

If the furnace is otherwise operating correctly, when you connect those blue wire ends you should hear the click of the gas valve open and then the clicking of the igniter. The furnace should then fire and run normally. If that happens then you know you've got a faulty sail switch.

I'm sorry if I'm over-explaining but I hope the pics below help. Make sure your jumper wire is stripped on both ends and push the exposed wire into the connectors of the blue wires. Maybe this is what you've already done. If not then give this a try and let us know how it goes.

I just installed another new sail switch I had ordered a couple days ago. Doesn’t ignite. That’s 3 different sail switches besides the original one.

[jsb5717]

Actually jumping the switches as I described is really the only way to know for sure if the issue is the sail switch, limit switch, or something else. It's possible to replace one bad component with another.

When it comes to troubleshooting I'm pretty anal about eliminating possible causes. If it were mine I would pull the wires from the sail switch and jump them like in my drawing. I would do the same thing at the Limit Switch. That way you will have eliminated both pre-ignition switches from the equation and completed the circuit to let the control board take the next step. If the furnace won't fire at that point I would get a new control board.

Until you do the actual troubleshooting steps you're just guessing. I hate guessing.

[Mark28RYR]

Originally Posted by jsb5717

Actually jumping the switches as I described is really the only way to know for sure if the issue is the sail switch, limit switch, or something else. It's possible to replace one bad component with another.

When it comes to troubleshooting I'm pretty anal about eliminating possible causes. If it were mine I would pull the wires from the sail switch and jump them like in my drawing. I would do the same thing at the Limit Switch. That way you will have eliminated both pre-ignition switches from the equation and completed the circuit to let the control board take the next step. If the furnace won't fire at that point I would get a new control board.

Until you do the actual troubleshooting steps you're just guessing. I hate guessing.

I removed the sail switch wires only, installed a piece of 14awg copper wire between the two connectors. Turned the unit on and the blower did not start. Furthermore I could hear what sounded like a high pitched whine coming from somewhere. Almost as if the control board didn’t like that too much…

[Mark28RYR]

Originally Posted by Mark28RYR

I removed the sail switch wires only, installed a piece of 14awg copper wire between the two connectors. Turned the unit on and the blower did not start. Furthermore I could hear what sounded like a high pitched whine coming from somewhere. Almost as if the control board didn’t like that too much…

And since then I cannot get the blower to come on. Pretty sure this happened last night when I tried it as well.

[ChuckS]

Originally Posted by Mark28RYR

Even with a In-Command system controlling the HVAC? I could see with a standard wall thermostat that being the case.

YES.. The Blue furnace wires coming from the furnace control board MUST BE CONNECTED to the wires ( what ever Keystone decided to use for color ) that run up to that ZONE 1 roof AC CONTROL BOARD>... PERIOD..

Look at the schematic.

Your In Command talks to the furnace control board via the Zone 1 roof AC control board using a simple two wire CANBUS...

Protocol IS RV-C.

[Mark28RYR]

Originally Posted by ChuckS

YES.. The Blue furnace wires coming from the furnace control board MUST BE CONNECTED to the wires ( what ever Keystone decided to use for color ) that run up to that ZONE 1 roof AC CONTROL BOARD>... PERIOD..

Look at the schematic.

Your In Command talks to the furnace control board via the Zone 1 roof AC control board using a simple two wire CANBUS...

Protocol IS RV-C.

See the attachment. This is what I’ve got and it’s always looked that way. I do not see any additional wires laying around and it appears that no other wire was crimped on with the lone blue thermostat wire.

[jsb5717]

Maybe ChuckS or Chuckster has an idea, but I haven't seen that symptom before. IMO, either something is wired incorrectly or the control board is whacky.

Just to prove the issue I would leave the sail switch jumped as you've done it and also jump the limit switch to see if you get the same result.

I haven't gone back through the entire thread, but have you checked to see if you have a resettable furnace fuse? If the fuse is black then replace it with a standard blue 15a fuse.

[ChuckS]

I personally think you need to START OVER with your trouble shooting and use a TS chart and service manual... Otherwise you are just running around in a circle jumping from this to that and will never get anywhere at this rate

https://techsupport.pdxrvwholesale.c...anual-2015.pdf

[Mark28RYR]

Originally Posted by jsb5717

Maybe ChuckS or Chuckster has an idea, but I haven't seen that symptom before. IMO, either something is wired incorrectly or the control board is whacky.

Just to prove the issue I would leave the sail switch jumped as you've done it and also jump the limit switch to see if you get the same result.

I haven't gone back through the entire thread, but have you checked to see if you have a resettable furnace fuse? If the fuse is black then replace it with a standard blue 15a fuse.

I had seen the fuse issue on another thread and tried that. Currently have the black one in but I’ll put try the blue one again.

[jsb5717]

Originally Posted by Mark28RYR

See the attachment. This is what I’ve got and it’s always looked that way. I do not see any additional wires laying around and it appears that no other wire was crimped on with the lone blue thermostat wire.

If the furnace has been working normally for the past 3 years then I wouldn't worry about which wires are not connected. Who knows how they wired it, or which colors they used, but it worked. So the current issue can't be related to wires that have never been connected.

[LHaven]

Originally Posted by Mark28RYR

See the attachment. This is what I’ve got and it’s always looked that way. I do not see any additional wires laying around and it appears that no other wire was crimped on with the lone blue thermostat wire.

Well, this is clearly wrong.

There are only four connectors on the furnace. Find the vacant one that's supposed to have a blue wire on it, and connect these.

On a separate note, keep in mind that there's nothing magic about inCommand when it comes to HVAC. It doesn't "exert control" per se. All it does is provide a GUI window into the functions of the existing HVAC gateway box. All the "features" it provides are actually provided by and in the gateway box, inCommand merely conveys your wishes to it. That's why once your desired HVAC behavior is set, it will continue to function even if inCommand goes offline or loses power.