Troubleshooting Floor Heat

[DrPhil]

Originally Posted by sartor

Hi DrPhil,

I've got a 2019 Dutch Star 4369 Spartan K2, and I seem to have a similar problem. Bedroom and bathroom heated floors working fine, but the living room floor heat stopped working about a month ago. Not sure if this has anything to do with it, but I had the floors (all three rooms) on all winter just as some additional freeze protection here in NC.

I'm trying to determine if my problem is simply with the relay. In your initial post, when you talk about "bypassing the relay," I believe that's accomplished by simply tying together the two wires that are wired to the two screw connectors on the top side of the relay, right? The relay (when operating correctly) is just internally jumpering those two wires.

And then when you checked resistance of the heater wire, you mean specifically measuring the ohms for the blue wire to ground, right? And I can simply use the green ground screw which is located in that same control box? And I should check that resistance with the floor heat controller turned *off*, correct?

Thanks for your insights!

Tom

I think that the most relevant thing you can do is check the ohms across the two wires in the blue cable. Mine should have been 20 ohms, and it was >1k implying an open circuit. This was verified when Newmar pulled the tiles and found one wire had come disconnected.

CONFESSION: The more I think about my problem, I came to the realization that I may have caused this issue. I remembered one time wherein I ran the FWS out and forgot the captain's chair was in the way pulling it hard to the outside. My guess is that the wire connection point - which runs through that area to the junction box in the storage bay - was stretched to the point of pulling apart by this mistake. It was about the same time that the floor heat stopped working, but I never put two and two together. Also, when I looked at the connectors which are actually fairly secure and shrink wrapped, they are not going to vibrate apart going down the road. Lesson learned - think hard about what has changed when something mysteriously stops working on an RV!

[DrPhil]

Originally Posted by OldWEB

I look at DrPhil's floor heat wiring and have to ask any Master Electricians here if that is legal in a MH or even bricks and sticks building? Can you use butt connectors on 120V wiring and not use a box for the connections? I have never seen that before.

I am not an expert on RV electrical code, but the picture I shared above isn't a high enough resolution to notice the details. The connections are soldered, crimped connectors which are heat shrink wrapped, and the silver wire is actually a grounded braided wire shield. I asked teh tech about the connections as they looked weird to me, and while I don't remember the specifics of his explanation, it seemed quite reasonable to me.

[alan1]

While looking for the break in my bedroom zone the tech stated that 9 times out of 10 the butt connector is the point that breaks. Based on my experience I think I will have them look at the connection first, rather than using the high technology stuff.

[OldWEB]

Originally Posted by DrPhil

I am not an expert on RV electrical code, but the picture I shared above isn't a high enough resolution to notice the details. The connections are soldered, crimped connectors which are heat shrink wrapped, and the silver wire is actually a grounded braided wire shield. I asked teh tech about the connections as they looked weird to me, and while I don't remember the specifics of his explanation, it seemed quite reasonable to me.

Don't get ME wrong, I have no qualms on doing it that way, if it is secure and tight, I just did not think it is allowed by code and MHs are 'suppose to be' wired by code. DC or low voltage AC circuits I understand, just not 120V being done that way. The only varience from a house to a MH are the cheap, plastic and crappy receptacles they use in MHs, THOSE I do not trust for higher amperage at all! And they are suppose to be 'legal'.

[Dutch Star Don]

Good post on how these floors can be repaired if there is an issue. Something to put in old memory banks.

[alan1]

Originally Posted by Dutch Star Don

Good post on how these floors can be repaired if there is an issue. Something to put in old memory banks.

When I put them in that spot, it is a one way trip.

[sartor]

Okay, got my issue resolved, so posting now in the hopes that some of this proves helpful to others.

First the good (and embarrassing) news: turns out my issue the entire time was simply a tripped GFCI. I *thought* I had checked that GFCI half a dozen times, including even plugging a nightlight into it to confirm it was on, but somehow/at some point apparently it was tripped, and so I simply wasn't even getting any 110V power to the LR floor heat control box, which is located in the front-most driver side basement compartment.

But to be thorough, I wanted to share what I've learned, as some of these things weren't obvious to me when I started:

1) As a reminder, this is all for a 2019 Dutch Star 4369 Spartan, that does *not* have the Silverleaf system. I'm still a bit unclear about what's the same/different between Silverleaf/non-Silverleaf, as far as components and wiring, but that's what I've got.

2) First thing that's confusing is figuring out exactly *where* all your GFCI circuits are located. Best as I can tell I've got *four* of them (that is, the ones that actually have the test/reset buttons located on them): there are two immediately above the circuit breaker box in the cabinet over the half bath toilet; there is one more in the half bath vanity above the sink; and a final one on the underside of the kitchen over-counter cabinet right of the refrigerator. If there are any more of them with buttons somewhere, I couldn't find them.

3) Now the LR floor heat control box is the square silver box inside the front-most driver side basement compartment. Inside that silver box is the *relay*, mounted in the lower-right corner. Coming into the bottom of that relay is a 2-wire yellow connector, which is what provides 12V to the relay if/when you turn on the floor heat via the switch inside the coach (the one next to/behind the passenger seat). When 12V is provided to that relay, it "picks" (you'll hear it click, if it's working), and that pick/click "closes" the relay, such that the two wires coming it at the *top* get jumpered together. While both of those wires are probably *black* at the relay connection itself, one of them comes into the compartment with yellow housing, and the other comes in with blue. The yellow-sheathed cable is the "hot" lead, bringing in the 110V on the black line (the other lines are white for neutral and copper/ground). The blue-sheathed cable is the "outgoing" connection, bringing the 110V to the floor heater itself, when the relay is picked/closed.

4) First thing to test is that you've got 12V coming into the yellow 2-wire connector on the bottom, when you've got the heat switch turned on inside the coach. Should be 12V across those two wires, if not, the problem is somewhere between the heat switch and that relay.

5) Next check for a bad relay by simply jumpering the two black leads at the top together. That effectively takes the relay out of the equation. If the floor heat starts working then, you've got a bad relay.

6) If the floor heat is still not working, check to see if you've got 110V at the *input* line (the black wire coming out of the yellow-sheathed group of three). To test that, you should disconnect that black wire from the relay, and also disconnect the two white wires from each other (the white wire from the yellow-sheath and the white wire from the blue-sheath are normally simply tied together, so separate them for these tests). Measure the voltage between the black and white wires from the yellow-sheath. If not getting 110V (which I wasn't), then you've got a problem somewhere upstream. In my case it was just the GFCI above the circuit breaker box, in the half bath cabinet above the toilet.

7) If you've got 110V coming in on the yellow-sheathed wires, then check the *resistance* of the blue-sheathed wires. Again, with the black wire disconnected from the relay, and the white wires separated from each other, measure the resistance between black (hot) and white (neutral) wires in the blue-sheath. You should measure about 20 Ohms. If not (typically a very high/infinite resistance, or very low resistance) then you have a problem in the heating element itself (either an open or a short).

Anyway, I realize that there's even more to it, particularly when you have a Silverleaf system (other's have talked about problems with the "TM-229 controller"), and I also realize that some of this is simply very basic electrical info, but I figured that it could prove useful for some other "amateur" owners.

Thanks to the others on the forum for the insights offered that helped me with my diagnosis.

Tom

[sartor]

Another post-mortem post, in the hopes this info proves helpful to others.

My living room floor heat seemed to go on the fritz again in the last several days, working at times and then inexplicably not working. I once again checked for 120V at the relay in the front-most driver-side bay, and it was not there. So went back again to check the GFCI circuit in the cabinet above the toilet in the half-bath. There are two paired GFCI outlets in that cabinet, one on the left and one on the right. In my 2019 Dutch Star 4369 at least, the one on the left is governed by breaker #2 (labeled "floor heat" in the breaker box), whereas the one on the right is governed by breaker #3 (also labeled "floor heat").

Turns out the main LR floor heat power comes through the left-side/breaker #2 GFCI, while the bedroom and master bath floor heat zones uses the right-side/breaker #3 GFCI.

The "mystery" for me was that *both* GFCIs *seemed* to be working. I could plug a nightlight into any of the four (two on the left, two on the right) outlets and it worked. So I thought, "GFCI must be good, right?"

WRONG! I noticed that the little green light in the upper corner of the GFCI on the left didn't seem to be working consistently. *Sometimes* it would be on, but other times it was off. And even when the *outlets* themselves continued to work. Attempting to push the "test" (trip) button on the GFCI, and then "reset," would only seem to restore it *sometimes*. Whereas the right-side GFCI was 100% consistent: green light was always on when it wasn't tripped.

So that go me thinking, and I pulled the GFCI out of the cabinet mount. Sure enough, while the "line" side black/white connections were good, as was the "load" side white connection, the "load" side black connection was no longer attached. Initially I thought, "AHA! All I've got to do is reattach it and I'll be fine."

But no luck: even re-attaching the "load" side black wire didn't get the green light working again, and still no LR floor heat.

So I took the GFCI circuit out of the wall cabinet again and inspected more closely, and I could see that the "load" side black connection appeared to be a bit melted. I can also report that on a few occasions in the past couple weeks, if I was connected to shore power and had all three AC zones turned on, *and* had my LR floor heat on (I know...crazy, right? But my DW likes the air cool and the floor hot, and our Chihuahua certainly likes the floor heat), then I was sometimes tripping my power protector with a code indicating "excessive current on line 1." So I eventually tried to make sure I never had all three ACs turned on with all three floor heat zones also turned on, and everything generally held up.

Anyway, given the seemingly damaged GFCI, I tried replacing it with a new unit, and voila! I've got the green light on the GFCI, and floor heat works again!

So hopefully this proves to be a helpful reference to other folks that run into floor heat issues. Check those GFCI outlets!

Tom

[OldWEB]

Originally Posted by sartor

Turns out the main LR floor heat power comes through the left-side/breaker #2 GFCI, while the bedroom and master bath floor heat zones uses the right-side/breaker #3 GFCI.
Check those GFCI outlets!

Tom

One other option I would like to add. If breakers #2 & #3 only feed those two GFCIs, then you could eliminate the wonky GFCIs receptacle with a GFCI breaker in the breaker panel and put in a normal receptacle in the cabinet. Many have had "hidden" issues with GFCI receptacles.

[DrPhil]

you know what. my 2017 DSDP also had a bad GFI in the half bath. this was before I had trouble with the floor, and i went to the trouble to change all my gfi's in the coach out reasoning that if one was bad, the rest in the lot are likely to have trouble. now the bad part about the one i had go bad is that it also took out the PCS control module when it arc'ed. not cheap, let me tell you, but that story is for another thread...

https://www.irv2.com/forums/f103/pcs...ue-508691.html

Btw, are GFI breakers made that will fit our panels? My impression is that breakers can be fairly proprietary to the breaker box.

[sartor]

Originally Posted by DrPhil

you know what. my 2017 DSDP also had a bad GFI in the half bath. this was before I had trouble with the floor, and i went to the trouble to change all my gfi's in the coach out reasoning that if one was bad, the rest in the lot are likely to have trouble. now the bad part about the one i had go bad is that it also took out the PCS control module when it arc'ed. not cheap, let me tell you, but that story is for another thread...

https://www.irv2.com/forums/f103/pcs...ue-508691.html

Wow, that was an unfortunate experience DrPhil! Guess I was lucky to get away as I did, with apparently nothing more than a bad GFCI outlet. I'm going to have to consider replacing them with GFCI breakers as OldWeb suggested. I *think* the only things those outlets are feeding are the floor heat sections (as well as the plug outlets themselves, of course). And as far as I can tell, those outlets are pretty much the *only* ones not fed by the *inverter*, which is how I discovered them in the first place, as I searched for a spot to plug in a power monitor that would inform me if shore power dropped, and not get "tricked" into thinking power was still on because it was getting it from the inverter.

Tom

[OldWEB]

Originally Posted by DrPhil

Btw, are GFI breakers made that will fit our panels? My impression is that breakers can be fairly proprietary to the breaker box.

Yes, the breaker has to be purchased knowing what style of panel it goes into, GFCI or regular breaker.
Just watch the width of breakers, some GFCIs can be "double wide" and take two spaces, but you should be able to source the narrow ones for your situation.