Fix a furnace two HVAC visits couldn't by talking the symptoms through with Claude
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- by Casey Donaldson (@caseyjdonaldson)
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Evidence: Described by posterThe person describes what happened in words, without screenshots or video.
Outcome
Casey Donaldson's furnace kept acting up. One HVAC technician charged $150 and gave a diagnosis that didn't fix it; a second charged $150 for a tune-up that didn't fix it either. Donaldson then described the symptoms over time to Claude, which narrowed the cause down to a few possibilities. $150 in parts later, the problem was fixed.
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Prompt Recreated prompt
The source didn't share its exact prompt, so we wrote this from what it describes.
Before you start, ask me 1–3 short questions about anything important that's missing below. Keep them quick. Then do the task, checking in with me at the key points. Goal: Work out the likely cause of a furnace problem that keeps coming back, so I can fix it or brief a technician properly. What I can give you (ask for whatever's missing): - Furnace make, model and rough age: [MODEL] - What it does and when, in order, including any error codes or blinking lights: [SYMPTOMS] - What technicians have already checked or replaced: [HISTORY] Safety first: on a gas appliance, don't have me touch the gas valve, burner or venting; if I smell gas, tell me to leave and call the gas company. Unplug or switch off at the breaker before any panel comes off. Rules: - Ask about the symptoms over time before guessing, and say which details would change your answer. - List the likely causes from most to least likely, with the check that would confirm or rule out each one. - Tell me which checks are safe for a homeowner and which need a technician. - If a part is the likely culprit, name the exact part to match to my model and roughly what it costs. - Check facts that can change (prices, opening hours, dates, availability, rules) against the official source, and tell me anything you couldn't verify. Output: A short ranked list of causes, the check for each, and the part to buy if one is clearly at fault. You'll know it worked when: the furnace runs normally again, or I can tell a technician exactly what to look at.
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Before you start, ask me 1–3 short questions about anything important that's missing below. Keep them quick. Then do the task, checking in with me at the key points. Goal: Work out the likely cause of a furnace problem that keeps coming back, so I can fix it or brief a technician properly. What I can give you (ask for whatever's missing): - Furnace make, model and rough age: [MODEL] - What it does and when, in order, including any error codes or blinking lights: [SYMPTOMS] - What technicians have already checked or replaced: [HISTORY] Safety first: on a gas appliance, don't have me touch the gas valve, burner or venting; if I smell gas, tell me to leave and call the gas company. Unplug or switch off at the breaker before any panel comes off. Rules: - Ask about the symptoms over time before guessing, and say which details would change your answer. - List the likely causes from most to least likely, with the check that would confirm or rule out each one. - Tell me which checks are safe for a homeowner and which need a technician. - If a part is the likely culprit, name the exact part to match to my model and roughly what it costs. - Check facts that can change (prices, opening hours, dates, availability, rules) against the official source, and tell me anything you couldn't verify. Output: A short ranked list of causes, the check for each, and the part to buy if one is clearly at fault. You'll know it worked when: the furnace runs normally again, or I can tell a technician exactly what to look at.
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Our rewrite with extra checks. The poster didn't test it.
Before you start, ask me 1–3 short questions about anything important that's missing below. Keep them quick. Then do the task, checking in with me at the key points. Goal: Work out the likely cause of a furnace problem that keeps coming back, so I can fix it or brief a technician properly. What I can give you (ask for whatever's missing): - Furnace make, model and rough age: [MODEL] - What it does and when, in order, including any error codes or blinking lights: [SYMPTOMS] - What technicians have already checked or replaced: [HISTORY] Safety first: on a gas appliance, don't have me touch the gas valve, burner or venting; if I smell gas, tell me to leave and call the gas company. Unplug or switch off at the breaker before any panel comes off. Rules: - Ask about the symptoms over time before guessing, and say which details would change your answer. - List the likely causes from most to least likely, with the check that would confirm or rule out each one. - Tell me which checks are safe for a homeowner and which need a technician. - If a part is the likely culprit, name the exact part to match to my model and roughly what it costs. - Check facts that can change (prices, opening hours, dates, availability, rules) against the official source, and tell me anything you couldn't verify. - After any fix, tell me what to watch for over the next week to be sure it's really solved. Output: A short ranked list of causes, the check for each, and the part to buy if one is clearly at fault. You'll know it worked when: the furnace runs normally again, or I can tell a technician exactly what to look at. Before you finish: re-read my goal and constraints, check your answer against each one, and list anything you assumed or couldn't confirm.
Source
https://x.com/caseyjdonaldson/status/2108576468976505097
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