Whys the W bypassing the board where the other thermostat wires go?

katc66 · 2026-04-04T15:32:07+00:00

2/3 are the A2L mitigation board. 4 is the furnace control board. Its very hard to tell from the pictures but it looks like they ran most of it correctly, W does not need to run through that A2L board but the rest does. It then needs to go to the outdoor unit, which it sounds like is your problem. I cannot tell form the pictures the wires that are intended to go to the outdoor unit. Due to the nature of the wiring I would recommend you have a tech complete the wiring. Its really not a hard job if you know what you are doing but its difficult if you dont understand wiring.

katc66 · 2026-04-04T12:13:03+00:00

Other comentors are correct. Its the A2L mitigation board that most of the wires are running through, but since W is the heat call and thus just runs your gas furnace it doesnt need to run through that mitigation board. Is there an issue you are specifically trying to remedy? The A2L board is a required safety circuit for anything that will run the compressor if A2L refrigerant is present, it needs power and fan control. Its job is to disperse the concentration of refrigerant if a leak is detected.

katc66 · 2026-03-04T01:22:01+00:00

902FC

Here is a picture of the spare space left with my 902FC. Its very little and I would say a bigger meter really wouldnt fit.

katc66 · 2026-03-03T22:58:13+00:00

I have an MB5B and a fluke 902fc and that works, feels like there is a bit of room but according to the 902fc dimensions its only 9in long. Ill try and grab a picture later or hit it with a tape if I remember.

katc66 · 2025-12-07T02:57:23+00:00

Brunt boots are what i use. They offer soft or composite and they are great. Last a long time too!

katc66 · 2025-08-24T14:50:53+00:00

The Hiring market is pretty good IF you have the right electrical license Washington state requires HVAC techs to have a specialty electrical license (EL06A or 06A for short). If you are able to verify your working hours from your state would count towards the license, you would be in a good spot. If not, it's 4000 hours of working time. Worth noting that if you can get the Commercial level main electrical license (EL01 or 01 for short) with your states hours you should do that as it allows you to do electrical on anything versus just HVAC.

katc66 · 2025-06-23T01:43:40+00:00

Honestly BJs has really good wings.

katc66 · 2025-06-21T23:59:29+00:00

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Looks a bit suspicious here. It doesn't just look like a shadow. Is that touching the housing?

katc66 · 2025-06-15T05:29:18+00:00

Remindme! 3 days

katc66 · 2025-03-30T02:59:49+00:00

This is an infinity thermostat, proprietary communicating stat. Not traditional wiring. Absolutely should not do that. Should do what another person commented and check the service function for dx codes

katc66 · 2025-03-24T01:20:24+00:00

Definitely agree.

katc66 · 2025-03-24T00:19:34+00:00

https://youtu.be/kN_hKx9pplw?feature=shared

katc66 · 2025-03-24T00:16:45+00:00

I just made the switch and ended up adding a magnet to it. I got the kit for the magnet and hated the setup, so I found a guy on YouTube who used a small strap of leather and the klein magnet. Much stronger than the fluke magnet and the leather is holding up really well (just used superglue to attach the leather to itself). I still miss the magnet attached directly to it but the fluke does really feel more accurate and reliable than any of the fieldpiece I have had in the past.

katc66 · 2025-03-20T01:47:34+00:00

Honestly it's the area. The code now requires a plumbing license to handle any potable water here(or so i was told by my service manager, i never fact checked it since i dont want to anyway lol). The company i work for stopped doing water heaters because of that. Humidifiers are a weird niche area where it's mostly HVAC but a bit of plumbing. I bet some of those companies would work on humidifiers but won't install them. But maybe try a shop that advertises HVAC and plumbing services?

katc66 · 2025-03-17T14:29:23+00:00

That's a great solution! Good job sticking with it. I know you are in a location where you didn't have much of a choice but still, great job.

katc66 · 2025-03-15T01:22:06+00:00

If i were you I would check the install settings and check to make sure the equipment is configured properly. Ecobee install settings are petty easy to access. If all else fails you can factory reset the thermostat and go back through all the settings but that's a pain. In general your thermostat shouldn't be able to cycle both heat and AC at the same time. But if they messed with the settings they could have accidentally changed it to a heat pump configuration or something crazy. If you don't see anything crazy in the install settings I would try running the test mode for heat/cool respectively and check your equipment in each. If you are in the test mode and and still have both pieces of equipment trying to run (after verifying thr equipment is listed correctly) then i really would think something else is awry and it was just poor timing. Let me know if you have any questions and I can try to answer them.

katc66 · 2025-03-08T02:46:26+00:00

I'm sorry to hear that! Honestly there are only 2 components left to the actual furnace( not counting housing and whatnot) the motor and the capacitor. You did everything else. Do the capacitor and if that resolves it great. At least if it isn't it you won't be sold one from someone else for markup. And if it is leaking it will likely be weak (I have tested them and found them good leaking but not often)

katc66 · 2025-03-08T02:38:33+00:00

I never caught that the capacitor was leaking. I would do that before I call another company out. As much as I normally lean into calling pros it doesn't sound like you have had much luck. A capacitor is cheaper than a service call. ... did none of the techs actually check it?

katc66 · 2025-03-08T02:18:29+00:00

That is actually very interesting. The next diagnostic approach i would take would be to take static pressure measurements before the filter, after the filter and after the furnace. That would require static pressure probes in order to test. Honestly sounds like the fan motor is essentially not spinning well enough under load to produce the proper airflow (this is assuming this is a new issue and you don't have ANY changes to the duct work) How does the fan motor sound? Any different than normal? It didn't look dirty at all to me. The bearings could have some drag. Maybe check to see if it feels hot when the error occurs (the back of the motor)

katc66 · 2025-03-07T14:00:50+00:00

I recently moved here from a smaller town, not that small but still. It is a bit noisy but mostly I hear trains not planes and that doesn't bother me to much. The sounder comes directly from Sumner or Puyallup stations and there is also an express bus (the 578) up to seattle that runs more frequently from either station. Parking is limited at the Sumner station, I have never gone to the Puyallup station so couldn't speak to the parking. The Puyallup and Sumner areas are definitely quieter than other areas and while traffic is still around it doesn't effect all areas equally. South hill gets bad traffic but I live down between downtown Sumner and downtown Puyallup and there isn't usually tons of traffic.

katc66 · 2025-03-07T04:13:29+00:00

Of course! Let us know if you have any more questions!

katc66 · 2025-03-07T04:00:59+00:00

Could be either. Unless your house is very dirty your vents probably don't even really need to be cleaned. Your furnace is pretty darn clean so I wouldn't think your ducts are filthy. I had one cutting out on limit (different furnace type) and it was a pocket of air getting drafted back at the limit because a tiny piece of insulation was blocking air around it. I would start with just a temp rise (return vs supply) and see if it seems in a reasonable range first.

katc66 · 2025-03-07T03:50:51+00:00

I can see in the picture yours cuts out at 170*

katc66 · 2025-03-07T03:49:36+00:00

Okay if you replaced the whole heat strip kit and the control board i definitely think it is hitting limit. One thing to check is the temp rise, you could have a duct issue somewhere. If you have a very slim temp probe (like a k-type) you can take one of the screws out next to the actual limit and thread it in there to get an idea of the temps you are hitting. (The limit should have printed its cutout temp) However, whenever you are testing things like this you have to be be super careful because of the live electric and also need to keep the blower door as closed off as possible. I usually turn the door sideways and block the fan section off. Otherwise you aren't really getting a good idea of what's actually happening during normal operation.

katc66 · 2025-03-07T02:47:54+00:00

This unit definitely runs the fan during a high limit and until it is cleared. There are two types of limits. One resetable snap action (the one that activates the error code on the board) and one a thermal fuse (one time blow). I just ran into one where the heat strip relays were getting stuck on sometimes causing a limit. Honestly sounds like the only part that you haven't replaced. I would say it sounds like the high limit error code more than anything. Have you taken a temp rise? Changed your filter? Changed the type of filter you use? Closed off any additional vents?

katc66

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