Hydronic heating: maintenance and repair: Cold radiators, or one room that never warms up?
Hydronic heating moves hot water through radiators, baseboards or loops under the floor. When air gets trapped in the lines or a zone valve sticks, some rooms go cold while others stay warm. We work on the water side of the system and get the heat moving evenly again.
- Open 24/7
- Free estimates
- Average arrival about 60 minutes
- Open 24/7 Call or text any time
- Average arrival about 60 minutes Across our service area
- Free estimates You know the cost before work starts
- Licensed & insured For homes and businesses
- 8+ years of experience Local to the Lower Mainland
In short
DrainX Plumbing Ltd. is a 24/7 plumber in Vancouver and the Lower Mainland, out to Langley. Maintenance and repair for hot-water heating: pumps, zone valves, air in the lines and leaking fittings. Call or text 778-794-1234. Average arrival is about 60 minutes, and estimates are free.
Last updated
What to watch for
Signs it’s time to call
- One room or one floor stays cold while the rest of the house is warm
- A radiator that's hot at the bottom and cold at the top
- Gurgling or trickling in the pipes when the heat comes on
- A circulation pump that has gone noisy, or gone silent
- Drips or green crust at a valve or fitting
- The pressure gauge keeps dropping and the system needs topping up
What we do
How we handle it
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Step 1: Find out where the heat stops
We go zone by zone, feeling the pipes to see which loops are getting hot water and which aren't. That tells us if we're chasing trapped air or a part that has failed.
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Step 2: Bleed the air out
Air collects at the high points and blocks the flow of hot water. We bleed the radiators and purge the loops until the water runs through without bubbles.
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Step 3: Repair pumps and zone valves
A circulation pump that has seized, or a zone valve stuck shut, leaves part of the house cold. We repair or replace the part and wait to see that zone heat up.
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Step 4: Check the expansion tank and fittings
The expansion tank takes up the extra volume as the water heats. When it fails, the pressure swings and fittings start to weep, so we test the tank and fix the leaks we find.
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Step 5: Annual maintenance check
Once a year we go over the pumps, valves, expansion tank and system pressure, and bleed any air. Problems are easier to fix in September than on a cold night in January.
Our work
Photos from our jobs
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Wall-hung boiler with copper piping, an air separator and expansion tanks -
Two heating zone valves on copper lines, labelled by room -
Wall thermostat set to heat, reading 23 degrees
What it costs
There’s no price list, because every job is different. Some jobs are a flat rate and others are quoted after we take a look. Estimates are free, and we explain the cost before any work starts.
Our work is covered by warranty. Coverage depends on the service, and we go over it with you when you book.
Offers on now
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$50 off your first service
Conditions apply. Call for details.
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5% off for seniors
Conditions apply. Call for details.
Mention the offer when you call: 778-794-1234
Before we get there
Walk through the house and note which rooms are cold and which radiators or baseboards are warm. That list saves time when we arrive.
Check that the thermostat for the cold zone is set to heat and turned up. A thermostat with dead batteries looks a lot like a heating fault.
If a fitting or valve is dripping, put a container under it and wrap a towel around the pipe. Leave the system’s own valves alone, since opening the wrong one can let out water that then has to be put back.
Clear a path to the mechanical room so we can reach the pumps and valves.
Hydronic heating: common questions
Why is one room cold when the rest of the house is warm?
Hot water isn't reaching that part of the system. Trapped air is the most common reason, and a zone valve that didn't open or a pump that has stopped pushing water will do the same thing. Tell us which rooms are affected and we'll start there.
Can I bleed a radiator myself?
If your radiators have bleed valves and you have the key, yes. Do it with the heat off and the radiator cool, hold a rag under the valve, and close it as soon as water appears. If the air is back within a few weeks, something is letting it in, and that needs a proper look.
Why does my system keep losing pressure?
Either water is leaving the system or the expansion tank isn't doing its job. A weeping fitting can lose water so slowly that it dries on the warm pipe and never makes a puddle. We test the tank and go over the fittings and valves until we find where the water is going.
How often should a hydronic system be checked?
Once a year is a good habit, and early fall is the best time, before you need the heat every day. The check covers the parts that wear, which are the circulation pumps, zone valves and expansion tank, plus a look at every fitting we can reach.
Guides on hydronic heating
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Hot water baseboard heater not working? What to check
Why a hot water baseboard or radiator goes cold: thermostats, trapped air, stuck zone valves and failed pumps. What to check and when to call.
Updated
Google reviews
What customers say
5.0 out of 5 on Google
From 23 reviews, as of November 2026
What reviewers mention
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Fair prices
Reviewers often say the price was reasonable. A couple say it came in well under what other plumbers had quoted.
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Quick to come out
Several mention the plumbers arriving when they said they would. Others describe a same-evening visit, and a call-out at short notice on a holiday.
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Careful, clear work
The work is described as thorough, tidy and professional. Reviewers mention clear explanations, upfront pricing and no pressure to buy more.
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Fixed what others couldn't
Two reviewers say DrainX solved a problem other trades had not. Several say they would hire DrainX again, and one already has.
A summary, in our own words, of the reviews on our Google profile as of November 1, 2026. The reviews themselves are on Google.
Reviews shown as written on Google.
Service area
Where we do this work
Need a plumber? Call or text us.
Tell us what’s going on and we’ll take it from there.
Open 24/7 · Free estimates · Average arrival about 60 minutes