Steam Heat Repair & Maintenance in Southern NH
Keeping New England's Original Heating Systems Running
Jolt Electric & HVAC services steam heating systems throughout Litchfield and Southern New Hampshire. Steam is one of the oldest central heating systems still in everyday use, and plenty of New England systems installed before 1900 are still running. You find it in the older building stock around Manchester, Nashua and Milford: pre-war homes, schools, churches, and certain commercial or industrial properties. Steam is its own trade, with different diagnostics, different parts, and different failure modes than a hot water boiler. We work on it in homes and in commercial and institutional buildings.
We serve homeowners, property managers, schools, and churches throughout Southern New Hampshire, including Litchfield, Nashua, Londonderry, Milford, Merrimack, Hudson, Manchester, Amherst, Hollis, Bedford, Derry, Goffstown, Salem, and Windham.
Why Steam Systems Need a Different Skill Set
Installation, Maintenance & Repair
A steam system isn't a hot water system with different pipes. On a one-pipe system there's no circulator pump at all. The boiler makes steam, the steam finds its own way up through the mains and into the radiators by pressure, and the condensate has to find its own way back down by gravity. Some two-pipe, pumped-return and vacuum systems do use a condensate or boiler-feed pump, and knowing which one you have changes the whole diagnosis. Every part of it depends on pitch, venting, and pressure being right.
That's why a contractor who works on modern hydronic equipment all day can misdiagnose a steam system. Turning the pressure up to fix a cold radiator is the common instinct, and it's usually wrong. Residential steam runs on ounces, not pounds. Most one-pipe house systems cut in around half a pound and cut out near a pound and a half, and much over 2 psi usually means something else is wrong. Larger buildings run a little higher, though not by much, and vapor and vacuum systems run lower still, measured in ounces on a vaporstat. Air vents close when steam reaches them, and extra pressure then keeps them from reopening, so trapped air gets compressed instead of pushed out and the radiator stays cold while the boiler wastes fuel.
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Steam Heat Repair in Litchfield and Southern NH
Installation, Maintenance & Repair
We repair one-pipe and two-pipe steam systems, and we work on the whole system rather than just the boiler. Repairs we handle regularly include:
Water hammer. That banging is condensate trapped where steam is moving. It usually traces back to pipe pitch, a failed radiator valve, or wet steam leaving the boiler, not to the noise itself.
Cold or partially cold radiators. On a one-pipe system that's almost always a venting problem, because air has to leave the radiator before steam can enter it. On a two-pipe system it's usually a steam trap that's failed closed.
Failed air vents. Main vents and radiator vents clog and stick. Sizing them correctly is what makes a system heat evenly instead of room by room.
Pressure control faults. A pressuretrol that's drifted or failed sends a system into territory it was never meant to run in.
Low-water cutoff problems. It's the safety device that keeps the boiler from firing dry. It gets tested and serviced, never bypassed.
Near-boiler piping. Undersized or incorrectly configured piping carries water up with the steam, and that one fault causes hammering, uneven heat, and wasted fuel all at once.
Leaking radiator valves and supply unions, plus wet returns that have rusted through.
Licensed Fuel Gasfitters in NH
Unlike many HVAC companies, we hold a New Hampshire Fuel Gasfitters License, which saves you both time and money.
One Company, One Call
You don’t need to hire a separate contractor for your fuel gas connection.
Faster Installations
You save time with a streamlined installation process.
Peace of Mind
You know your heating installation is safe and complies with all state regulations.
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Steam Boiler Maintenance That Protects the System
Heating Installation, Maintenance & Repair
Steam boilers need more attention than hot water boilers, and the maintenance is different. Sediment and oil residue in the boiler water cause surging and carryover, so skimming and flushing matter more here than on a closed hydronic loop. Annual service on a steam system includes flushing the low-water cutoff, blowing down the mud leg, checking the water line and glass, testing the pressure control, running a combustion analysis, inspecting and replacing failed vents, and verifying that the system still heats through evenly across a full cycle.
Done consistently, that's the difference between a steam boiler that lasts decades and one that fails in the middle of a cold snap.
Steam Heat for Schools, Churches, and Commercial Buildings
We service steam systems in schools, churches, and commercial buildings as well as homes. Larger buildings are more likely to run two-pipe distribution with steam traps and a condensate or boiler-feed pump, and they run at somewhat higher pressure than a house. So service covers the traps, the return side, and the pump, not just the boiler. When heat is uneven from one wing of a building to the next, the cause is usually in the distribution rather than the boiler itself.
Steam heat has a reputation for being loud and wasteful. A properly balanced system is quiet, and it burns far less fuel than a neglected one. It won't match a modern condensing hot water boiler on paper. A steam boiler makes steam at roughly 214 to 218 degrees, so the condensate coming back is far too hot for the flue gases to condense, and flue-gas condensation is where a condensing boiler earns its last ten points of efficiency. But most of the complaints we hear come from systems that were patched by people who didn't know what they were looking at, not from the technology itself.
We'd rather repair and rebalance what you've got than sell you a conversion you don't need. Cast iron radiators outlast almost everything else in a building, and the original distribution is already in the walls. When a steam boiler has genuinely reached the end, we'll price a replacement in kind and walk you through your options so the choice stays yours.
With over 30 years of experience, our veteran-owned company is trusted for honest recommendations, quality work, and transparent pricing. We're a licensed and insured New Hampshire mechanical contractor, and we work with premium-quality parts. If your steam heat is banging, uneven, or costing more than it should, schedule a visit and we'll tell you what's actually wrong with it.
What Our Customers Say
At Jolt Electric & HVAC, we take pride in delivering top-quality workmanship and reliable service to every client. See what our satisfied customers have to say about working with us.
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Whether you need electrical, heating, or cooling services, Jolt Electric is here to help. Our team is dedicated to delivering high-quality work, transparent pricing, and unparalleled customer service to homeowners and businesses throughout New Hampshire.
Service Area:
We proudly serve homeowners and businesses throughout Southern New Hampshire, including Litchfield, Nashua, Londonderry, Milford, Merrimack, Hudson, Manchester, Amherst, Hollis, and Bedford.