VR9205Q1010 honeywell valve on goodman furnace drops out - poor contact circuit board plug

archibald tuttle

this furnace has been the most reliable in our fleet. nothing but change the filters for 5 years. but the gas valve just started dropping out if you touch or even brush the harness. seem to have narrowed it down to the long 5 pin (4 used) connector that is part of the circuit board and effectively mounts this board to the pair of main solenoids (there is a third solenoid with a two wire plug that engages for 25% boost to highest btu operation. this is unaffected but doesn't help because the main solenoid is the gas shut off.

The main solenoids have 4 2" long flat prongs about 3/16" wide , 2 for each solenoid , to carry the 24V to each head. the center prong on this 5 pin setup is not used on this valve. both the prongs which are exposed once the circuit board is removed and the slightly sprung contacts in the plastic covered connector integral to the circuit board have slight darkening where they have been making contact. not black carbon but it appears to be just enough of a surface oxidation of some sort that any shaking whatsoever causes the conduction to collapse and the valve closes. sometimes the furnace will recycle but sometimes it won't light unless i apply pressure to the connector. then everything is fine for a few cycles and then the nightmare starts again.

i can't imagine i'm lucky enough to be the only one who has run into this problem. I have another valve on the way but i wonder if the springs in the connectors wear out easily on these and i'm going to run into the same problem on the new valve in a few years. and its frustrating because there isn't anything wrong with the valve itself, i just cannot get these connectors to maintain connection. it would be very finicky but i suppose i could solder wires from the solenoid tabs to the circuit board. anyone else dealt with this? all brilliant ideas accepted, along with commiseration.

thanks

Jamie Hall

Springs have lost their tension. Can you perhaps find a replacement plug? And wire it in? Try Digi-Key -- they have dang near every electronic widget you might ever want... Or you might try just cleaning the contacts; there are contact cleaners for that sort of thing.

EBEBRATT-Ed

Kind of a hack but maybe temporally jamb a pc of tinfoil in their to fill in the gap.

archibald tuttle

Jamie, i tried physically cleaning but that only exacerbated the lack of spring tension although the boiler did light even with the lesser tension although still unreliable. i wonder if digikey would have this. i have no idea how to even designate the connector and it is physically soldered onto the board. i'll post some pictures tomorrow morning.

meantime EDEBRATT i was thinking along those lines, trying to put something else in with the connector pins to tighten the fit. maybe aluminum foil, or even a piece of #14 solid romex might work.

in terms of whether this is a common problem, I used to get great tech help from goodman, but now it is under amana and the tech line was underwhelming. and honeywell who has often been spot on, was no better today on real knowledge of their own valve.

Jamie Hall

Digikey almost certainly has the right connector; it's not likely to have been a one off. The trick is to find it in their catalogue... There doesn't just happen to be a part number molded or printed on it, does there?

Tim McElwain

If I am reading this correctly this is a two stage Smart Valve application. If that is correct I had a similar problem and was able to resolder a connection. A picture of what you are dealing with would help.Different versions of the two stage Smart Valves have had different connectors.

BobC

usually the white housing has a part number molded into it. Also check the solder connections on the back ofthat board, sometimes it's a shaky solder joint that makes the pin iffy.

Bob

archibald tuttle

thanks all, sorry in this season it took me so long to get back to your helpful suggestions. not a solder problem (although i wonder what the hell the printed circuit board actually does anyway and why bother. this drives me as crazy as them getting rid of analog timers on washing machines.

this was all pin contact issues and to make matters worse it was both the board connector onto the solenoids and the wire harness connector from the boiler to the board so correctly diagnosing which connection was dropping out at any given second was almost impossible.

if this valve were 20 years old, i wouldn't have any complaints but it has only been in service 3 or 4 years. i'm looking through my receipts file to figure out when we installed it. i've had very occasional problems when the old school spade terminals didn't make contact (or the rivet from the spade terminal to the valve had been challenged by rough removal of the spade and was loose and making sporadic contact). But this was literally the first time I ever had the valve unplugged. On a routine check during really cold weather i noticed what i thought were excessive temperatures in the supply plenum and upon checking it showed a heat rise slightly in excess of the spec (plenum was 145 with a heat rise of 73 degrees which is slightly in excess of the specified 65 degree maximum) and i had clean filter and it was on the highest fan setting so i was looking in to whether i could take more control of the two stage logic maybe to put a sensor to drop out highest stage if plenum went over 140 kind of thing, and i unplugged the harness to test whether the operation of the valve was independent or additive (i.e. did high stage (ambiguous whether to call that 1st or 2nd) involve calling 24V call to both high and low stage or where they independent. (unfortunately neither goodman nor honeywell provide a good theory of ops for the valve). i got that figured out, plugged it back in and the boiler starts up and i'm just cleaning up the harness with a zip tie before putting the cover on and it drops out starting this little adventure leading me to suspect poor contact at both the incoming harness connector and the 5 pin connector that mounts the circuit board to the valve by sliding onto the 'main', i.e. low stage primary solenoid connections.

i tried cleaning the contacts in the 5-pin connector with 1/16" drill by hand as i could see a little discoloration of the tabs in the contact area which kind of worked but the spring connectors that were already too light tension for their own good (not sure if that was factory tension or if they had relaxed) were even looser when i was done so i'm thinking the design and spring tension were at issue insofar as the 5-pin connector. you can see from the picture that i macguyvered those by inserting a piece of weedwacker twine into the middle of the u-shaped connector from the back. the contact is actually made to the pins on the outside of one long side of the U and so if the tension exerted by the bottom of the U is insufficient you don't get solid contact and it is easily subject to the circuit collapsing over the slightest jostleing (sp?) of the connector. so this is along the lines of the recommendation i got for adding aluminum foil to bulk up the connector pins, but i was a little worried about stray conductive material touching the wrong thing and so the little light bulb went off that weedwacker twine is not conductive and has a little bit of material resiliency and by placing it inside the U it didn't keeps the U more strongly open but doesn't interfere with the contact between the pins and the outside of the u. it worked like a charm. plug was snugger than it had ever been.

so as soon as that was done it became clear that the harness plug ( 3 pin white on the right of the circuit board in the picture) was also loose enough to cause problems. it turns out the connectors in the harness side are round rolled female and are easily subject to opening -similar to a spade style where the female terminal has gone loose because the rolled grips at either side have opened a little. you can generally crimp each side of the a female spade lightly with pliers to restore a degree of tension in that style fitting. not at all as readily addressable with this plug and, although you et a new connector when you buy a new valve (which i did to have on hand, i had the thing all fixed by the time i got it) i didn't see an offering for the connector only (may be that is something for digikey. next time i have the front off i will look more closely for molded numbers on the connectors.

I also wonder if i am imagining things or if the discoloration i've been observing in areas of contacts reflects that even with a new harness connector there might be slightly more resistance or issues with the pins on the valve portion of the connector which is on thsi stupid (unless somebody tells me it doesn't something smart and useful) printed circuit board which i also don't find offered separately, but maybe i don't know how to look deeply enough into the honeywell parts inventory.

in any event, on the harness connector tubular female side of this connecter, the common was the worst and i paired back plastic to just expose the end of the round metal female and crimped it lightly and then used some 24 gauge phone wire between the crimp and the plastic to try to sustain that reformation. without pairing the plastic back i added these wire bits around the other two conductors prophylactically. put everything together (i always use silicone dielectric paste on connections like this hoping to limit this kind of prblem in the future. who really knows if i'm doing anything but increasing the fortunes of permatex - but id digress) and, voila, problem solved. not a hitch since then. 3 hours later the new valve arrives (of course, but glad to have it on the shelf as my 'repairs' don't have a tested life yet.

i don't think i contributed to the problems with that plug through testing. i didn't jamb the probe all the way in, i just touch the ends but it isn't inconceivable i exacerbated a problem that was on its way, and i exerted no unusual force or testing on the 5 pin that was equally flaky leading me to wonder what is up with the contact material and plugs styles used here and wondering why we need circuit boards and can't just have spade connectors (or god forbid screw terminals) all of which i solder and heat shrink and have never had a problem (except on old boilers that i haven't serviced) . this was not an outdoor installation or particularly damp or problematic, i just don't get where this kind of stuff should be loosing contact after only a few years in service.

btw the staging is calling both H and L(or main) for high operation and the high solenoid is conveniently connected by two wires off the left end of the circuit board as depicted so i can intercept that with a plenum limit. a little finicky but doable. (and of course i have to worry whether the connector for the two wires will manifest some problem, albeit at least if that drops out it just means i'll be running on low stage which in this case was giving me 130 deg. plenum temperature and basically could keep up in all but coldest days and even then would perform marginally on its own without the high stage.

I'm trying to remember the oil nozzle that was in the furnace we replaced. partly by instinct i felt like we were undersizing the replacement but my partner in crime insisted this would handle the house and he was right. one has to remember that 115 thousand btus of truly condensing output is more like 130 thousand in theory and I don't have efficiency calcs from the old furnace so it could have effectively been even more of a difference.

saga over. back to your coffee. talk amongst yourselves.

unclejohn

When I look at that CB and I think back to the furnaces I worked on in the early 70's, those furnaces needed either a belt tighten or the pilot relit. That was at least 90% of the service calls. Now they make stuff like that little CB and have gotten 20% on average more eff. But at what cost to the consumer? In terms of dollars spent on repairs and cost of operation I'm not sure it's worth it.

archibald tuttle

uncle john (got a band?)

right, and i don't think this CB contributes to efficiency. it is the equivalent of a light switch which would have done the job 100% better. all the stage control is back on goodman's black box. completely unnecessary from what i can see. over engineered. they still might use an under performing connector these days rather than trust us techs to put the terminals back on the right flag but that would at least limit the number of potentially bad connections.

BobC

This is all because they use 3 cent tin pins and sockets rather than 20 cent bronze phosphor pins and sockets. So by saving 5 or 10 dollars on a furnace or boiler they make the equipment 80% less reliable but at least it keeps the number cruncher s happy.

Bob

unclejohn

@archibald tuttle
I just noticed your screen name.
https://www.youtube.com/watch?v=dht_3NziwSw

archibald tuttle

unclejohn, nice pull - here's my version. what would you do if this guy rappelled through your window to fix your furnace!?

archibald tuttle

bobc, second that about crappy connectors. penny wise and pound foolish all over. with more logic control these new units require massively more service. if they don't ensure simple s#$% like good connection how can you check the logic.

There isn't much going back if the cast iron boiler got deep sixed, but in most residential applications i'd be in no rush to deep six reliable cast iron boilers with simple safety controls where you often get limited condensing return temps.

Furnaces i must admit are low hanging fruit for condensing technology and i realize that can be facilitated with variable stages, variable fan speeds, etc. although even in that case i'm thinking the extent of digital logic isn't necessarily defensible. why not just setpoint feed and return air sensor that could operate the stages based on temp rise and high limits. most of that stuff could be handled with analog setpoint controls although digital can provide some sophistication. But whether digital or analog, If my name were on the product it can't possibly be acceptable engineering to create connectors that fail 4 years in. But maybe thats just me.

These furnaces have a reasonably attractive price point and of course we're all cost conscious. I think the bean counters completely miss that cost consciousness is in context. I will gladly pay more for quality of connections, servicability, etc.

And part of that is sticking to proven designs like spade connectors (employed on the goodman board itself for instance). or, god forbid, screw terminals. It doesn't have to be space age in every aspect. . . . and when the thing ain't working, its just more space junk.

Jamie Hall

The price point is where the newer types of connectors come in, on the manufacturing end. They are less reliable than a properly assembled screw or better yet soldered connection, or the older big spades. But... they can be put together by unskilled labour or robots, and put together correctly (believe it of not) every time. That they often don't last in service is not a consideration.

It's all part of the if it breaks throw new parts at it mentality. That we all seem to like the fix it mentality marks us, I'm afraid, as being a bit old fashioned...

ratio

If it's broken, the new model is probably out anyway, so why mess with it? </humor>

BobC

I have looked at the Molex harness of my Carlin EZgas/ Smith g8 with suspicion since it was installed 5 years ago. If that connection ever gives me real pause for concern I will cut both connectors off and install a Jones strip and spade lugs in it's place.

If it's good enough for military equipment it's good enough for my boiler.

Bob

archibald tuttle

jamie, interesting point on cutting assembly labor. but its choosing the crap connectors that bugs me. i understand components are going to fail. i understand that connectors might fail although having a chain of them in the same circuit give up suggests to me that they are not up to the service in the field they are aimed at even if they meet the theoretical requirements. I don't want to jump all presumptive so maybe this has not been commonly experienced on this model goodman furnace or similar honeywell valves, but the only option we have for pushing back is to call this out.

archibald tuttle

BTW, Tim - i know you are all over this stuff. I did check the solder connections and mountings on the board. What exactly is 'smart' about this valve? other than an on-off switch, what logic is involved?

FranklinD

The saga of loose pins - I see them so often I may as well see them in my sleep too. I work on fire trucks, squad cars, and garbage trucks, and I swear they have cornered the market on terrible pin-fit. Molex, Weatherpack, and the dreaded Deutch Connector.

Usually I can tighten them up using a bent paperclip or a small pick to “work” the tension mechanism (spring, spring tab, etc) but some are beyond salvation...then you do whatever you can. I’ve even clipped the wires off the connector & found crimp-on terminals that “grab” the pin tightly, and used them as the repair. Sometimes you do what you have to do.

Good luck!

archibald tuttle

Franklin, thanks for chiming in from the 12V(?) DC world. absolutely my first awareness of the exacerbated contact problems in lower voltage was automotive although (thank god) I haven't personally experienced as much trouble with the Toyotas and GMC medium duties i'm running. upon reflection, I'm not sure why. i'll keep knocking on wood. but the increasing reliance of these cars on sensor input and logic outputs for operation gives me the heebie jeebies about planned obsolescence in the harness. The mid 90s camry wagons that are my pick-up truck of choice seem to be pretty bombproof in that respect. fingers crossed.

what kinds of circuits, i.e. custom accessories or engine/emissions functions or . . . (?) are showing the most problems. we both certainly have the same approach to improving contact once establishing that the plug is the problem.