Heat pumps run year-round, which means they fail in any season. We diagnose the reversing valve, defrost, and charge issues that trip up general HVAC techs.
A furnace gets a break every spring. A heat pump never does. The same outdoor unit that pulls heat into your home all winter reverses in July to pull heat out of it, so it carries a year-round workload almost no other piece of home equipment matches. That is the quiet reason heat pumps fail: they simply run more hours than a straight furnace or air conditioner, and they fail in every season — a no-heat morning in January, a no-cool afternoon in August, and everything between.
When that happens, the diagnosis matters more than the part. A heat pump can lose its heat in a dozen ways — a stuck reversing valve, a failed defrost board letting ice choke the coil, a low charge that reads fine in summer but starves the system in the cold, or auxiliary heat quietly carrying the whole load while your electric bill climbs. Guess wrong and you replace a good part while the real fault stays. That is where a tech who understands heat pumps earns the visit.
Standard Services is a licensed and insured, family-owned and women-owned company based right here in Glen Mills. We repair heat pumps of every brand across Delaware and Montgomery Counties, offer same-day service when your system quits, and give you a straight diagnosis and an upfront price before any work begins.
If your heat pump runs but pushes cool air when it should be heating, the reversing valve is the prime suspect — it may be stuck in cooling. It can also be a low charge or a stuck defrost cycle. Each points somewhere different, which is why we test before we replace.
The reversing valve is what lets one machine both heat and cool. When its solenoid or slide sticks, the system locks into a single mode — heat that won't cool, or cooling that won't heat.
A spike in your electric bill often means the auxiliary electric strips are carrying the load the compressor should be. Something upstream has failed and the backup heat is masking it — expensively. We find why the heat pump stopped pulling its weight.
Here's what isn't a problem: a light coat of winter frost on the outdoor coil is completely normal. Your heat pump runs a defrost cycle that melts it off automatically every so often. What is a problem is persistent, thick ice — a solid block that never clears, or ice climbing over the top of the unit. That points to a bad defrost board, sensor, or fan, and it's worth a call.
A heat pump is far more sensitive to charge in heating mode than an AC is in summer. A small leak a system could shrug off in July will leave it unable to keep up in January. Topping off isn't a repair — we find and fix the leak, then charge to spec.
A heat pump that trips the breaker, hums but won't spin up, or clicks on and off every few minutes usually has a failing capacitor, contactor, compressor, or control board. We meter the electrical side and read pressures to pin down which — before anything gets swapped.
Same-day heat pump repair across Delaware and Montgomery Counties — a straight diagnosis and an upfront price before we start.
Here is something the industry doesn't say out loud: plenty of capable HVAC techs are stronger on straight air conditioning than on heat pumps. An AC unit only cools. A heat pump does everything an AC does and runs the whole thing backward to heat your home — adding a layer of parts and logic a summer-only system never has, and failures a cooling background doesn't train you to read.
Start with the reversing valve, the component that flips the refrigerant flow between heating and cooling. It has no equivalent on a plain AC, and diagnosing a sticking one takes knowing how the system should behave in both modes. Then the defrost board: the brain that decides when to briefly reverse into cooling to melt frost off the coil, and when to stop. When it fails, the symptom is ice — but the fix is electronics, not a scraper.
Add auxiliary-heat staging, where the controls must bring in electric backup only when the compressor truly can't keep up, or your bill balloons. And refrigerant charge, which in heating mode is far less forgiving than in cooling — a charge that looks fine in July can leave a system helpless at 20 degrees. Reading those four systems together is the expertise a heat pump actually demands.
We diagnose heat pumps as heat pumps — testing the reversing valve, defrost logic, aux-heat staging, and charge as a connected system, so you don't pay to replace a good part while the real fault keeps hiding.
A geothermal, or ground-source, heat pump works on the same principle as an air-source unit — it just trades the outdoor coil for a loop of pipe buried in your yard, pulling heat from the stable temperature of the earth instead of the outside air. That makes it efficient, and the part you actually service is a compact unit indoors, with no equipment sitting out in the weather.
Because the loop is buried and sealed, the failures we see are rarely the loop itself. Far more often it's the same refrigeration and control side you'd find on any heat pump — a reversing valve, compressor, control board, or charge issue — plus geothermal-specific pieces like the water-source heat exchanger and the loop circulator pump. Read those wrong and you spend money chasing the loop when the fix was indoors all along.
We service and repair geothermal heat pumps throughout Delaware and Montgomery Counties. If your ground-source system has lost heating or cooling, is short-cycling, or is throwing a fault, we'll diagnose the refrigeration circuit and the loop side together. Call 610-545-1000 and let us know it's a geothermal unit so we arrive ready.
We watch the system run in the mode it's failing in, then meter the electrical side and read refrigerant pressures. Because we test the reversing valve, defrost, charge, and controls together, we find the actual fault instead of guessing at the likeliest part.
Once we know what's wrong, you get a clear explanation and a flat, upfront price before any repair begins. If a part needs ordering or a fix isn't worth it on an aging system, we tell you that honestly so you can decide with real information.
We make the fix with quality parts — valve, board, capacitor, contactor, compressor, or a proper leak repair — and when refrigerant is involved we charge to the manufacturer's spec rather than topping off. Charge accuracy matters most in heating mode.
Before we leave, we confirm the heat pump switches and runs correctly in both heating and cooling, check that defrost behaves, and make sure aux heat only kicks in when it should. You get a system that's proven working, not just started up.
"Reading pressures in heating mode — where charge accuracy matters most"
"A reversing valve mid-repair — the part a straight-AC background rarely touches"
"Testing the defrost board — the fix when ice won't clear on its own"
Standard Services provides heat pump repair throughout Delaware and Montgomery Counties. Whether you're in Thornton, Villanova, or right here in Glen Mills, we're your local team.
Plus Devon, PA.
Tell us what your heat pump is doing and we'll get you on the schedule — same-day service in most cases. Prefer to talk it through? Call us directly.
Same-day heat pump repair across Delaware and Montgomery Counties — diagnosed right, priced upfront, and proven working in both modes.
Glen Mills’ Trusted HVAC & Plumbing Experts
Copyright © 2026 All Rights Reserved.