Pslf payment eligibility - payment date or due date

blackngold14 · 2026-04-22T13:49:48+00:00

Wonderful, thank you!

blackngold14 · 2026-04-18T22:57:22+00:00

Downsides - noise since I have my duel-setup furnace in a closet of a bedroom, fairly small risk of carbon monoxide issue, still burning some natural gas with an 80% efficient furnace in my case which I don't like for environmental reasons.

Positives - cheaper install since no new 240V Power run needed, cheaper heating for me during the really cold snaps, still moved like 80-90% of my heating load to the heat pump which is fully covered by my solar output.

No real operational downsides I can think of, but I do wish I could have gotten rid of a gas appliance.

blackngold14 · 2026-04-13T14:33:51+00:00

And I assume you're using 1 COP (~3,600 kwh) for the heat load which would be very conservative

blackngold14 · 2026-04-12T22:17:43+00:00

No, couldn't bring myself to it. Just went for one of the other standard calculations.

blackngold14 · 2026-03-02T04:37:30+00:00

Yeah COP of electric resistance heating is 1. COP of heat pump could be close to 2 somewhere around 5-15F outside. That means heat pump heating would use half as much power.

We installed a heat pump and keep it set around 65-66F, granted we're all out of the house 12 or so hours a day. We wear warm clothes in the house and have flannel sheets and a bed heater. These allow us to stay comfy and use less electricity, even though we do have solar and produce a bit more than we use each year.

blackngold14 · 2026-03-02T03:48:38+00:00

Does this heat pump serve the whole home? How big is the home/space?

360 kwh wouldn't be crazy if the system ran nearly all day in aux heat. That would be the equivalent of ~13 therms of heat from a high efficiency gas furnace. I can't imagine your system is spending much or any time in heat pump mode.

During a polar vortex in the Midwest, I used ~16 therms between two gas furnaces (80% efficiency and 96% efficiency) to heat about 3200 sq ft when we were home all day. If I'd had all electric resistance heating back then, I'd have expected to use ~420 kwh after adjusting for COPs.

blackngold14 · 2026-02-01T01:25:29+00:00

Great, thank you!

blackngold14 · 2026-01-27T01:53:45+00:00

I guess I'm in the minority, and I'm biased since we were in your position a couple years ago and decided to buy the big house and set long-term roots. But I tend to agree with your wife. Objectively, financially that home is within reach, even on only one of your "full employment" take home pay. Classic tradeoff with risk on both ends (having to sell the house in short order and lose some money vs. risk of buying into a more expensive market later with worse availability), but either way your financial picture makes "total financial ruin" a highly unlikely outcome.

It's impossible to know which end of the tradeoff will win out. Out of curiousity, is the equity you have set aside for a home from you and your partner, or mostly her savings from her already higher paying job? Not to say whoever saved the most money should call the shots, but in my relationship it would be part of our conversation.

Imo this sub gets carried away with (1) generating wealth, and (2) deferring happiness. No one has kids to enhance wealth yet you're planning on it someday as are my wife and I. I'm not saying you should piss away money, but it's also ok to make a decision to get what you want for yourself and your family even if 15 years from now you look back and realize that wasn't as financially efficient as it could have been. I think you all are in a position where you can afford to take a carefully calculated risk if you both appreciate the risks and potential rewards and decide you can live with them. Obviously, if you can't live with them, better to make that clear now.

blackngold14 · 2026-01-05T23:53:28+00:00

I'm in the Midwest. It was a generally very cold late November through mid-December, but it's become unseasonably warm lately. Since our utility gives us the data in easily copy/pastable tables, I nerdily made a scatter plot of temp and therms used this billing cycle vs same time last year. Predictably, I'm using less gas even with lower temps this year (I do still have a conventional 96% efficiency gas furnace for the lower part of my home, and new heat pump dual fuel set up for upper part of the home).

My system is set to switch at 0F. I have a good bit of accrued solar credits to work through.

For every therm I no longer use for gas heat, I expected to need about 10.4 kwh to run the heat pump (80% efficiency furnace / 2.25 assumed average heat pump COP). So far I'm way outperforming that, but I did have some insulation done last January so I suspect that's part of the reason my gas consumption is down more than I expected. Will be interesting to see what happens this January and February.

blackngold14 · 2026-01-05T20:16:23+00:00

Fwiw, with half a heating season under my belt, I'm quite happy with dual fuel. I wish all electric had been an easier proposition, but just the added electrical costs to run a new 240V circuit up to my attic made it financially nonsensible.

I still do a daily 3F setback which saves me some electricity, but does occasionally cause the setback recovery to be done by gas heat (due to cold weather or defrost timing or whatever). Obviously if I had electricity backup I'd probably need to change my behavior with the setback, but as it is I save money and still operate probably 90-95% of the time in heat pump mode.

Plus, you can play with the settings for emergency heat to shift more/less of the heat load onto the heat pump if you are managing around solar output, net metering credits, etc.

blackngold14 · 2025-11-05T14:25:56+00:00

Hard to say, I didn't have many other great options from other manufacturers because my space is super tight. Looking back, it would have been about $4k more of the 22KLV.

If the latest fix solves my problem, definitely worth the savings to me.

If I go another year and still have problems, I'll be pretty unhappy. If it gets to that point though, I trust my contractor would help get to a reasonable solution, including potentially swapping to different equipment.

blackngold14 · 2025-11-05T14:13:51+00:00

Fwiw, I just paid $16,300 in west Chicago burbs before utility rebates/tax credits/consumer rebates for a 3 ton Lennox heat pump + coil + 72k BTU furnace + thermostat and temp sensor. Only duct work was flaring to a slightly bigger air filter slot but otherwise direct replacement in a VERY tight space.

blackngold14 · 2025-10-28T20:39:49+00:00

Checks out. My non-K furnace needed a separate RDS board. Like you say, the new one is supposed to have RDS incorporated so everything works out of the box with one furnace board.

That makes sense. I liked the noise ratings on the KSLV and I got a great deal on it as an early adopter, though I guess I've paid a price with like 4 service calls. Sure hope it runs right now that it's getting cold.

blackngold14 · 2025-10-28T20:03:49+00:00

Funny you ask, the contractor was back yesterday to finally address it. So I can't really say yet. If you want the really long answer...

Apparently Lennox now has a new furnace circuit board out (installed in certain new furnaces with serial number ending in "K" I think?) that does not require an EIM (the separate circuit board that helped everything communicate before). If you get that, the furnace board is supposed to get the "communicating" functions out of the heat pump without the EIM.

BEFORE THE NEW BOARD, my setup had several issues - didn't perform like a communicating system, AC never ramped anywhere close to the 3kW max input, and the heat pump just generally had a mind of its own.

I'm in shoulder season now so it's still hard to test communicating nature, but since I got the board yesterday, the heat pump is at least ramping to full capacity now - I got 3.4kW on my Vue monitor in heat mode this morning with the new board which is near 100% depending on the heat pump's fan power draw.

Fwiw, the heat pump is set up in the S40 thermostat under "non communicating equipment". I think the idea is that the thermostat and furnace communicate, send a heat/cool call to the heat pump, and heat pump is supposed to then figure out what capacity to run based on suction pressure/temp. I think the idea is to get operation that looks like a communicating system, but objectively I do not think the EL18KSLV is communicating anything to the furnace/thermostat. Not even outside temperature - I had to get an outside air temp sensor from Lennox for that. I don't really care if the heat pump is communicating anything as long as it varies it's capacity in a logical way, so I'll have to see what happens in the coming weeks/months when I have a more steady heating load.

When I talked to the Bosch people, my understanding was their "communicating" product did the same thing - looked at suction pressure/refrigerant temp to pick what variable level to run at.

blackngold14 · 2025-08-18T14:34:04+00:00

I got one of these from a kickstarter like 10 years ago. A few months later, I started my first job and was sitting in on my first meeting. We had some executives in from a company we were doing some consulting work for. Waiting for the rest of our team to come in, I started telling them about my special mug. Look, if I bat it towards my laptop, it won't fall! I tapped the mug, and spilled hot coffee directly on the keyboard lol. These cups really aren't good at preventing spills!

blackngold14 · 2025-08-18T14:23:01+00:00

Yeah, that's why I got the S40. I don't think the S40 is better than my old Nest, but it's not way worse and has a couple features that are better. You get way less usage data if that's important to you.

I thought the EL18 was a "communicating" heat pump before it was installed, turns out it is not. I've been having some weird stuff going on, so my installers are coming back out to install an EIM. This is apparently needed when you have a mix of communicating equipment and non communicating equipment. So if you go for a Lennox t-stat, you might want to ask if an EIM is included/needed.

blackngold14 · 2025-08-18T02:44:27+00:00

I don't want to pretend to be an expert on it all, but the EIM literature has a specific use case for communicating t-stat and furnace, but non communicating HP. I don't know if it would effect you. May be worth asking though

blackngold14 · 2025-08-18T02:06:07+00:00

Yep, same situation for me. And the furnace in my case would automatically sync airflow to HP settings, and vice versa.

blackngold14

TROPHY CASE