Boiler will not fire
Ignition, controls and gas supply are checked, and pressure is read. A boiler locked out on low pressure never fires until the water side is sorted.
No heat, leaks and cold radiators across Denver
Boiler repair Denver for radiators and radiant heat
Boiler repair is a different kind of no-heat call — a boiler that quits, leaks, or leaves half the radiators cold, where water, pressure and air in the system matter as much as the burner. Lion Tech Home Services works on the boiler, the piping and the radiators as one system.
Call any time
Call (720) 806-7634
The phone is answered any hour, day or night. Ring (720) 806-7634, say what the boiler is doing, and the visit is talked through from the symptoms.
Call Now (720) 806-7634 →Phone-only booking — name the boiler fault and the visit is set.
Boiler, piping, radiators and controls — one system.
About this service
Boiler repair in Denver: what the visit covers
Repair is diagnosis plus the mechanical work that restores heat to a hot-water home: boiler, circulator pump, expansion tank, piping, radiators or baseboards in the rooms. The visit starts with pressure, temperature and burner readings, because a boiler that will not fire and one that fires without heating are different faults.
Boilers are more common in Denver than in newer cities. Whole streets of pre-war homes in Capitol Hill, Park Hill and Washington Park were built around boiler heat, with cast-iron radiators or baseboards and no ductwork at all. A boiler short-cycling, losing pressure or leaving radiators cold is usually telling the water side of the story, not just the burner.
- ✓Boiler, pump, tank and piping checked together
- ✓Pressure, temperature and burner read
- ✓Radiators and air in the system checked
- ✓Leak traced to its source before any fix
What's included
What a boiler repair visit includes
The fault is found across the whole water system, explained, fixed where it failed, and heat is tested room by room. That is the shape of every visit.
✓
Full diagnostic at the boiler
Burner, heat exchanger, ignition and controls are checked, and pressure and temperature gauges read. A boiler that will not fire and one that fires without heating are different faults.
✓
Circulator pump tested
Pump tested for flow and noise. A pump seized or running dry leaves radiators cold even while the boiler itself runs hot.
✓
Expansion tank and pressure checked
Expansion tank checked for a failed bladder, system pressure read hot and cold. Pressure climbing when the boiler fires points to the tank, not the boiler.
✓
Air in the system found
Air trapped in radiators and high points stops water moving. Radiators are bled, and the air separator and vents are checked so air does not return.
✓
Leak traced
A leak at a valve, a joint or the boiler itself is traced to its source. Water on the floor under a boiler has a cause, and topping up pressure without finding it only delays the next call.
✓
Room-by-room heat test
Once fixed, a full heat cycle runs and the radiators are checked room by room, so heat is known to reach the far rooms as well as the near ones.
How it works
How a boiler repair visit works
01
Call and describe the system
Ring (720) 806-7634 and describe what the boiler is doing — no heat, a leak, a noise, cold radiators, pressure dropping. If you smell gas, leave the house first and call 911 or the gas company.
02
Diagnostic at the boiler
Pressure and temperature gauges are read, burner and controls checked, circulator pump and expansion tank tested.
03
Plain-English explanation
Nothing is touched until you have heard what failed, why it failed, and what the repair involves. A fault sitting in the piping rather than the boiler comes with that news too.
04
Repair and testing
Once agreed, the failed part is replaced or the leak repaired, and a full heat cycle runs with radiators checked room by room.
05
Walkthrough before we leave
You are shown what failed, radiators that need it are bled, and the thermostat is set with you. Later questions go to the same number.
Tools & methods
Tools and methods we bring to a boiler call
Boiler diagnosis is water work as much as burner work. These tools read both sides of the system.
Pressure and temperature gauges
They read system pressure hot and cold, and supply and return temperatures. Pressure climbing as the boiler fires points straight at the expansion tank.
Multimeter
Ignition, controls, circulator pump and zone valves are tested. A pump pulling too much current shows up on a meter before it seizes.
Combustion analyzer
Carbon monoxide and flue temperature are measured to confirm the boiler burns cleanly and vents correctly once it is running.
Leak detector
It checks every gas joint after a repair, and helps trace water leaks at valves, joints and the boiler body.
Radiator key and bleed kit
Trapped air is bled from radiators and high points so water can move through the whole system again.
Infrared thermometer
It reads radiator and pipe temperatures room by room, so a cold radiator is traced to its cause — air, a stuck valve, or a balancing problem.
Common situations
Boiler trouble we see across Denver
Boiler hot, radiators cold
Situation
In Denver, a boiler fires and gets hot, but radiators stay cold and the house never warms.
What we check
Circulator pump tested, system checked for trapped air. A seized pump or an airlock leaves the boiler hot and the house cold.
Pressure dropping every few days
Situation
A boiler in Washington Park loses pressure over a few days and keeps needing to be topped up. No water shows on the floor.
What we check
The expansion tank is looked at, and a slow leak hunted at valves and joints. Pressure that keeps falling always has a cause.
Kettling and banging from the boiler
Situation
A boiler in Denver makes a kettling, banging noise when it fires, and the radiators gurgle.
What we check
Scale and sludge in the heat exchanger are checked, along with air trapped in the system. Kettling is the sound of water boiling where it should be flowing.
Problems we solve
Boiler problems we fix in Denver every winter
Boiler calls mostly follow a few familiar patterns. These are the ones seen most across Denver, and the way each is approached.
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Radiators cold at the top or the far end
A radiator cold at the top holds air; one cold at the far end has a flow problem. Radiators are bled and pump and balancing checked.
Boiler losing pressure
Pressure that keeps dropping means water is leaving the system — a leak, a failed expansion tank, or a relief valve letting go. Lion Tech Home Services finds which one.
Boiler leaking water
Water under a boiler can come from a valve, a joint, the relief valve or the boiler body. It is traced to its source before anything is replaced.
Proof you can check
Boiler repair proof you can check
Many Denver boilers heat radiators in pre-war brick homes, so a repair visit starts at the radiators and the water side, not only at the burner — pressure, flow and trapped air decide the diagnosis.
Customer reviews
What Denver Customers Say
Lion Tech Home Services has 11 Google reviews, all five stars, and a 5.0-star rating to match.
“Absolutely excellent service - very responsive and able to work until the job is done right. Was super impressed by the support on our fireplaces and furnace - nice to have all up and working again! Many thanks”
John-Erik Emmetsberger — Google review
A radiator cold at the top usually holds trapped air and needs bleeding. One cold all over usually has a flow problem — stuck valve, seized pump, or balancing issue. Radiators are checked room by room to find which it is.
Pressure that keeps dropping means water is leaving the system. Usual causes are a slow leak at a valve or joint, a failed expansion tank, or a relief valve letting go. Topping up without finding the cause only delays the next call.
It depends on the failed part. A bleed and a pump replacement are very different jobs, so diagnosis comes first and you hear what is wrong and what the repair involves before any work begins. Ring (720) 806-7634 and describe the symptoms.
Lion Tech Home Services fixes boilers across Denver, from Capitol Hill and Washington Park to Highland and Central Park. Ring (720) 806-7634 — the phone is answered around the clock.
Ready when you are
Boiler trouble? Call and talk through your system
Ring (720) 806-7634, describe what the boiler is doing, and the visit is talked through on the call, including the first thing to check.
Call (720) 806-7634 →
Request an appointment
Contact Lion Tech Home Services
Lion Tech Home Services, Denver — call (720) 806-7634, open 24 hours.