Tempstar Heat Pump noise diagnosis in Greater Vancouver
Your Tempstar sat outside quietly for four winters. Now it makes a sound you can hear from the bedroom, and you want to know whether it is going to cost you a compressor.
The sound itself is real diagnostic data. Technicians triage by it before a single panel comes off, because the noise family narrows the list fast: impact sounds live in one part of the machine, electrical sounds in another, refrigerant sounds in a third. What matters is describing it accurately.
This guide walks the families one at a time — what each generally indicates, what a technician checks and in what order, and which sounds mean stop using the system now. It also covers the noises a healthy heat pump makes on a wet Lower Mainland January morning, so you are not paying someone to diagnose a defrost cycle.
Describe the sound properly before anyone opens a panel
Four questions narrow the fault list more than any tool does. When does it happen — at startup only, continuously while running, at shutdown, or randomly through the day? Where is it — the outdoor unit, the indoor air handler or furnace cabinet, or the ductwork? Does it change with fan speed or compressor stage? And is it new, or has it slowly grown louder over a season?
Timing matters because startup and shutdown are when the system moves: motors accelerate, refrigerant pressures equalize, the reversing valve shifts, and metal that is loose announces itself. A sound only at those moments is a different investigation than a sound that runs steady for twenty minutes.
Location matters because ductwork transmits noise beautifully. Homeowners in East Van character houses regularly report a “banging heat pump” that turns out to be sheet metal oil-canning in a duct run under the floor, twenty feet from the equipment.
Record it on your phone. Stand at the outdoor unit, then at a supply register, then at the indoor cabinet, and label each clip. A thirty-second recording gives a technician more to work with than a paragraph of description, and it captures intermittent noises that politely stop the moment a van pulls up.
Then check the obvious: anything leaning against the outdoor unit, anything blown into the top grille, a garbage bin against the cabinet.
Banging, thumping and booming
Impact sounds mean something is hitting something, or something under stress is suddenly releasing. That is a small list, and it is the list a technician works through by elimination.
At the outdoor unit, a single hard bang at startup or shutdown often traces to compressor mounting — the rubber isolation grommets under the compressor feet harden and crack with age, and once they fail the compressor’s starting torque lets the whole body lurch and strike the base or the refrigerant lines. A repeating bang while running suggests the fan blade contacting the shroud, a bent blade, or debris riding the blade.
Inside, a boom on startup from the ductwork is usually panning or plenum flex, not equipment. A blocked return, a closed-off room, or an undersized return path raises static pressure and makes flat sheet metal pop each cycle.
Order of checks: cut power at the disconnect, look for physical contact and debris, hand-spin the fan for drag or wobble, inspect the isolation grommets and hold-down hardware, then check line-set contact where copper touches framing or the cabinet.
Do not run a unit that bangs and then quiets to a metallic scrape. That combination points toward internal mechanical failure, and running it makes the repair larger. Shut it down and get eyes on it.
Rattling, buzzing and chattering
Rattles are the most common call and the least alarming, but they are also the easiest to misjudge, because a serious electrical buzz sounds a lot like a loose panel from ten feet away.
Mechanical rattle sources, roughly in the order a technician checks them: service panel screws backed out, the top grille fasteners, the fan shroud, a loose disconnect box or whip strap, and debris inside the base pan — fir needles, cedar, and the gravel that gets kicked in from a side-yard walkway. Lower Mainland units sitting under conifers collect an astonishing amount of organic material each fall, and it migrates down onto the base and against the fan.
Electrical buzz is different in character: it is steadier, it has a 60-cycle hum quality, and it comes from the control compartment rather than the top of the unit. A contactor that chatters — rapid clicking, sometimes with a burnt-plastic smell — points to control voltage or contactor problems and belongs to a technician. That compartment carries line voltage even when the thermostat is off.
Homeowner territory: tightening exterior cabinet screws with the disconnect pulled, clearing leaves from around the unit, and removing anything resting on the cabinet. Not homeowner territory: anything behind the electrical access cover. That is a licensed-technician job, full stop.
Humming with no start, or a hum that never goes away
A hum without motion is a specific and useful symptom. The unit is receiving a call and energizing something, but the load is not turning.
The classic version: you hear a low hum from the outdoor unit, the fan is not spinning, and after a short period the hum stops or the breaker trips. Technicians look at the run capacitor first, because a weak or failed capacitor leaves a motor energized but unable to start, and a stalled motor hums while it heats. From there the checks move to the contactor, the motor windings themselves, and the compressor start components.
A related version: you spin the fan blade with a stick through the grille and it takes off. That is a strong hint toward a start-component problem — and it is also the moment to stop and call, not a repair.
A continuous hum that has always been there and hasn’t changed is often just transformer or contactor coil noise, normal for the equipment. What matters is change. A hum that got louder over one season, or that is now accompanied by heat or odour at the cabinet, is not background noise.
Capacitors hold a charge after power is removed. That alone rules the control compartment out for homeowners. Pull the disconnect, leave the cover on, and book service.
Squealing, screeching and grinding
High-pitched and abrasive sounds almost always come from a rotating component, and they follow a predictable progression: quiet, then a squeal on startup, then a squeal that lasts longer each week, then grinding, then failure.
Bearings are the usual cause. Outdoor fan motors on the coast live a hard life — driving rain, salt-laden air near Boundary Bay, White Rock and the North Shore waterfront, and long shoulder seasons of constant runtime. A dry or worn bearing squeals at low speed and screeches at full speed. Indoor blower assemblies do the same, though a blower squeal is often masked by duct noise until it is well advanced.
Grinding is different from squealing and should be treated differently. Grinding means surfaces that should not touch are touching. It can be a fan bearing that has already failed, a blower wheel dragging on the housing, or something inside the compressor. In every one of those cases, continued running does damage. Shut the system off at the thermostat and pull the outdoor disconnect.
A short chirp on startup that vanishes in a second is usually benign belt-or-bearing seating on older indoor equipment. A chirp that becomes a squeal that becomes a screech is a motor telling you its schedule. Replacing a fan motor before it seizes is a far smaller job than dealing with what happens after.
Hissing, gurgling and whooshing
Refrigerant sounds confuse homeowners because several of them are completely normal and one of them is not.
Normal: a whoosh or short hiss each time the system switches between heating and cooling, or enters and exits defrost. That is the reversing valve shifting and pressures equalizing, and on a Tempstar heat pump in a damp Vancouver winter you will hear it several times an hour on a cold, wet night. Normal: a brief gurgle as refrigerant redistributes on shutdown. Normal: metering-device flow noise at the indoor coil, especially in a quiet hallway closet installation.
Worth investigating: a hiss that is continuous rather than momentary, gets louder over weeks, or is accompanied by declining heating output, longer run cycles, or ice forming on the indoor coil or on the larger copper line. Those together suggest a charge or airflow problem, and both need instruments — pressures, temperatures, superheat and subcooling — not guesswork.
A loud sustained hiss with visible oily residue at a joint should be treated as a refrigerant leak. Turn the system off and call. Refrigerant handling is regulated work, and topping up a leaking system without finding the leak just repeats the problem next season.
Bubbling or gurgling from the indoor drain area is usually condensate, not refrigerant — check the trap and the drain line first.
The sounds you should not chase
Heat pumps are noisier than the gas furnaces most Lower Mainland homeowners grew up with, and a fair share of service calls end with nothing wrong.
Defrost is the big one. When outdoor temperatures sit near freezing with high humidity — which describes most of a Vancouver, Burnaby or Surrey winter — the outdoor coil frosts and the unit periodically reverses to melt it. During defrost you may hear the outdoor fan stop abruptly, a whoosh from the reversing valve, a change in compressor pitch, and then steam rolling off the coil while the unit sounds briefly like it is running in cooling. Ten minutes later it returns to heating. That entire sequence is designed behaviour.
Variable-speed and multi-stage equipment adds its own vocabulary: the compressor ramping up and down instead of hard on/off, the indoor blower slowly changing pitch, longer and quieter run cycles rather than short loud ones. Homeowners moving from single-stage equipment often read “it runs constantly” as a fault when it is the design.
Expansion and contraction ticking from ductwork and line sets as they warm is also normal, particularly in older homes with long metal runs.
The test is change. A sound your system has always made, at the same volume, on the same schedule, is almost never the emergency. A new sound, a louder sound, or a sound with a symptom attached is worth a look.
Coastal corrosion, strata rules, and when to stop and call
Two local factors change how heat pump noise plays out here.
First, salt air. Units within a few blocks of the water in White Rock, Tsawwassen, Steveston, West Vancouver and along the Fraser take real corrosion damage to fan hardware, cabinet fasteners, base pans and coil fins. Corrosion loosens things, and loose things rattle. It also seizes bearings early. Rinsing the outdoor coil with a garden hose on low pressure, on a schedule, is one of the few genuinely useful things a homeowner can do — power off first, and never a pressure washer.
Second, strata bylaws. Many buildings and townhouse complexes set outdoor-unit noise limits, and municipalities have their own noise regulations. If neighbours are complaining, get the actual bylaw language from your strata before assuming the equipment is faulty. Mounting changes, isolation pads and relocation are sometimes the answer rather than repair.
Shut the system down and call HeatLand at (604) 330-3812 if you hear grinding or metal-on-metal, if a bang is followed by silence, if there is a burning or hot-plastic smell, if the breaker trips repeatedly, or if a sound comes with ice on the equipment.
HeatLand has serviced Metro Vancouver and Fraser Valley heat pumps since 1999, on all major brands, and we will give you a free written no-obligation estimate before any repair work starts.
Quick Checklist
- Record 30 seconds of the sound at the outdoor unit, at a supply register, and at the indoor cabinet, and note whether it happens at startup, while running, or at shutdown
- Walk the outdoor unit and clear leaves, needles, gravel and anything leaning on or blown into the cabinet, with power off at the disconnect
- Check that exterior cabinet and grille screws are snug — loose fasteners cause most rattles, especially on units near salt air
- Confirm the sound is not a normal defrost cycle: fan stops, a whoosh, steam off the coil, then back to heating within roughly ten minutes
- Verify indoor airflow — check the filter, and make sure returns and supply registers are not blocked or closed off, which causes duct booming
- Stop the system and call a licensed technician for grinding, metal-on-metal contact, a burning smell, repeated breaker trips, a hum with no start, or noise plus ice on the coil
| What you hear | What it generally points toward | Homeowner or technician |
|---|---|---|
| Bang or thump at startup or shutdown | Compressor isolation mounts, loose hold-down hardware, or line set contacting framing | Technician — inspect before continued use |
| Rattle or buzz from the cabinet | Loose panel and grille screws, debris in the base pan, or a chattering electrical contactor | Homeowner for exterior screws and debris; technician for anything electrical |
| Steady hum, fan or compressor not turning | Start components, contactor, or motor winding problem; motor stalled and heating | Technician — capacitors hold a charge, keep the cover on |
| Squeal that becomes a screech or grind | Worn or failed fan or blower bearings, or a wheel contacting its housing | Technician — shut it off, running it enlarges the repair |
| Continuous hiss with weaker heating or coil ice | Refrigerant charge or airflow problem; possible leak needing regulated handling | Technician — pressures and temperatures required, not guesswork |
Frequently Asked Questions
My Tempstar heat pump makes a loud whoosh and stops the fan every hour. Is it broken?
That pattern usually describes a defrost cycle, which is normal in a wet Lower Mainland winter. Near-freezing damp air frosts the outdoor coil, so the unit briefly reverses to melt it: the outdoor fan stops, the reversing valve whooshes, steam rolls off the coil, and heating resumes within roughly ten minutes. If it runs far longer than that, repeats constantly, or the coil stays iced afterward, book a diagnostic.
Can I just tighten the screws myself to stop a rattle?
Exterior cabinet and grille fasteners, yes — pull the outdoor disconnect first, leave the electrical access cover in place, and snug them by hand. Clearing leaves, needles and debris from around and on top of the unit is also fair game. Anything behind the control compartment cover is not: it carries line voltage, and capacitors can hold a charge after power is removed. That part is licensed-technician work.
What does a specific error code on my Tempstar board mean when it’s noisy?
Code meanings vary by brand, model and year, so read the exact code off your unit and check it against that unit’s own manual or the label inside the cabinet rather than a generic list online. Codes generally fall into families — airflow, pressure, defrost, communication, motor or control faults — and the family plus the sound tells a technician far more than the number alone does. Write the code down before calling.
Does living near the ocean actually make my heat pump noisier?
It genuinely can. Salt-laden air along the water in White Rock, Tsawwassen, Steveston and the North Shore corrodes fasteners, fan hardware, base pans and coil fins. Corrosion loosens components that then rattle, and it shortens bearing life so squeals show up earlier. Rinsing the outdoor coil with a garden hose on low pressure, power off, helps. Never use a pressure washer — it bends fins and makes airflow problems worse.
My strata says my outdoor unit is too loud. What are my options?
Get the actual bylaw wording from your strata council first, along with any municipal noise regulation that applies, because the limit and the measuring point matter. If the equipment is operating normally, the fix is usually mounting rather than repair: vibration isolation pads, a different mounting method, a sound blanket where the manufacturer permits one, or relocating the unit. If it is genuinely faulty, a diagnostic identifies which. We can assess both.
Should I keep running the system until a technician can come out?
For rattles, mild hums that have always been there, and normal defrost sounds, yes. Stop immediately for grinding or metal-on-metal contact, a bang followed by silence, a burning or hot-plastic smell, repeated breaker trips, or a hum where nothing turns. Those all get worse with runtime and turn small repairs into large ones. Shut the thermostat off, pull the outdoor disconnect, and call HeatLand at (604) 330-3812.
Reviewed by the HeatLand Heating & Cooling team — licensed, insured, TSBC-certified HVAC contractor serving Metro Vancouver & the Fraser Valley since 1999. Error codes, specifications, pricing and rebate programs vary by model and change over time; confirm details against your unit’s own manual, a written quote, and the manufacturer or CleanBC/FortisBC. If you smell gas or your CO alarm sounds, leave the home and call the gas utility and a licensed technician from outside.