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# service events by date:


03/17/2006: purchase date

xx/xx/xxxx: needed a replacement "exhaust unit" (external exchanger) fan. Once installed it spun backward.
They claim it was a defective motor, and were here well after dark replacing it with another motor, which
worked fine. (all under warranty)

xx/xx/xxxx: came home from work one summer evening, 92F in the house. HVAC was on, trying to cool down, but
vents were pumping out heat. Tech comes out and checks outside unit, "the furnace is calling for heat", so the
reversing valve outside was doing heating instead of cooling. Can't open the furnace to check the board since
it has a kill switch on the door panel that will kill power to the furnace when the panel is opened. Open it,
test, looks fine. Close the hatch. NOW it works fine. Gremlins! So now that kill switch is taped over in
case it does it again. (it never has)

2012/01/14: installed "whole house humidifier" accessory, taps water off the water heater. Simple turn dial
humistat control in the basement.

2012/07/17: was running humidifier in the summer since the house was a bit dry. AC wasn't working well, called
a tech and they educated me that you don't run a hot water humidifier while trying to run the AC. Doh!

2013/12/17: wake up Saturday morning to 54F. Furnace keeps turning on and off, never heating. Checked intake
and exhaust ports on side of house, clear. Called tech. Comes over, says airflow problem - no I checked that.
No it's the vacuum sensor not working. Common problem with colemans, his last call this morning was this exact
same problem on another coleman. Hope you have another spare in the truck? sure do, common issue. OK just
replace it. No he wants to show me the pricing sheet first. (uh oh) It's "normally $300 but since you're a
club member we'll discount parts, $200 for you." Uh no I am not an idiot, that's a bit if plastic, a spring
a membrane, and two strips of brass, there's no way that costs $200 let alone $300. Checked online. MSRP on
this exact vacuum sensor is $18. GET OUT. He gets this evil grin and tells me "your furnace won't work if I
don't fix it!" My furnace will be running before you can get down the street now get out. Hotwired it, got
the furnace running. Took sensor upstairs, open. Exercised the vacuum hard a few times. Restored switching.
Swapped it back in. Ordered a ($18) spare. Spare is still sitting on the furnace shelf 10 years later.
Scamming repairmen piss me off. Found out later that this group's techs work on commission and it's in their
financial best interest to scam customers.

2019/02/28: furnace won't turn on. find blown 2a fuse on board. replace, pops immediately. tech comes out,
wires in external unit rubbed through insulation, shorting. He figures I can probably fix this myself, and
just run on gas heat until then

2019/06/10: finally decide to just have the tech fix the exhaust short. he replaced wires, added split loom
tubong over them to protect wires.

xxxx/xx/xx: humidifier stopped working. Humistat isn't working anymore, won't close contacts. Just wired it
to be on all the time. Excessive humidity caused particle board in attic to sag, had to tear it out.

xxxx/xx/xx: Made my own basic humistat that ran for awhile. Eventually it quit working properly.

xxxx/xx/xx: bought a new humistat, same exact as original. Its a simple bimetallic spring type, no heuristics.
The valve now cycles rapidly during transitions, sometimes for 20 seconds or more. I imagine that's really hard
on the contacts AND on the value, maybe what killed the first one.

2023/04/02: external unit rattling loudly. regular maintenance check time, I tell them to send a tech to check
it out while doing regular work. They sent a salesman instead, who clearly had no idea how HVAC worked and
could only keep repeating to me "it's old, it needs to be replaced". Called a tech from another place. He comes
out, bad bearings in the motor. Not super cheap but $450 beats a new furnace.

2024/01/06: fan runs but doesn't heat. start capacitor is open, ordered two start caps and a run cap. Replaced
both (kept old run cap as a spare, and I have a spare start cap) The capacitor actually failed weeks earlier but
I was able to switch to "emergency heat" (gas) so replacing the capacitor wasn't an emergency.

2024/12/21: replaced humistat with one I constructed myself. It's got heuristics in it that should prevent the
valve from oscillating at a single set point. I currently have it set to turn on when humidity drops to 45%,
and turn off when the humidity gets up to 50%.

2025/07/03: got home to find the house at 76 degrees. Furnace on but exhaust unit not running and maybe a faint
odor in the house. Was after 5pm on the day before 4th of July and a weekend, started to schedule Young on an
overtime call. Got the exhaust running again by power-cycling the furnce, although the air wasn't as cold as I
was expecting. Wasn't cooling the house down very fast (if at all?) and the HP line was only mildly warm to
the touch. Got progressively hotter throughout the following Friday July 4. Tried resetting the furnace again
but didn't help. Since the fan wasn't running AND the house wasn't cool, it doesn't seem like a starter cap
failure since the compressor and fan have separate capacitors. Maybe a bad contactor? (20A 240v fuses are good)
I can't imagine a worse time for this to fail, right at the start of a three-day holiday weekend and heat wave.

2025/07/05: got up early and went out to test the capacitors. The small black Start capacitor tested open.
Searched around and found the spare Start Capacitor I bought the first time I had to replace it. Swapped,
AC is running again, I don't have to suffer two more days and pay blood money for a tech. Will need to order
more spare Start Capacitors, probably should get better quality ones than the junk I bought recently. At least
I was smart enough to buy a spare, although the stores in town probably carry it. The cap was 18 months old.
Listing says "100% LIFETIME PROTECTION: Enjoy reliable performance with our lifetime protection,
ensuring that your product will always be covered for any defects or issues that may arise." so I may be able
to get a free replacement. At least the house is cooling off, it got up to 95 yesterday AND today, hottest
days of the year so far. (and the lights were flickering a little from all the compressors in the neighborhood
trying to keep up)

2025/07/06: about to go to bed and hear loud BANG from outside. Not surprising with all the fireworks still
going off but I also saw a flash of light around the blinds out the North bedroom window. A little later I
noticed the temp in the house getting a little warm. Outside unit fan isn't spinning. Might have blown the
new capacitor up? I've got a lot going on in the next few days so will have to wait to look at it. In the
meanwhile, will be ordering another (warranty) 220v starter cap, as well as a 330v starter cap and a new
starter relay. (if the starter relay is stuck closed, that'd blow up the starter cap, which isn't designed to run
continuously) And I may have a capacitor mess in the housing now if that new one blew up instead of just
opening up electrically like the previous one did.




last updated 07/08/2025 at 08:20:58 by make_www_index.command version 2025.06.28.A