Hot water baseboard heat repair tips & troubleshooting FAQs:
Here in a question and answer format we give simple steps to get that cold or not warm-enough hot water heating baseboard back to snuggly warm again. We report on frequently-asked "cold heating baseboard" questions and answers that can help diagnose and fix baseboard troubles in your building.
This article series provides common hot water heating baseboard questions and answers that will help diagnose & repair most common heating baseboard troubles including no-heat or leaks or other problems.
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These questions & answers about troubleshooting and fixing problems with forced hot water baseboard heat were posted originally at BASEBOARD HEAT.
Interesting I can't find any published data on how much dust and dirt reduces the efficiency of radiant fin tube. Dirty coils have a significant effect on forced air systems.
I would expect the the negative effect would not be as much, but who knows for sure. Does anyone know the approximate percent reduction in efficiency form dirty and dusty fin tube?
I have not seen quantitative analysis, but take a look in the photo shown here. When the baseboard is dust clogged like shown you're probably blocking at least 50% of the air flow through the heater.
The five diagnostic steps above still apply for hot water radiators, but you've got an additional advantage: there may be a radiator control valve (red circle in our photo) to check (is the radiator turned on?), and there may be a handy air bleeder valve near the top of the radiator (blue circle in our photo).
If your heat is not from a heating baseboard (like the unit shown at the top of this page) but instead is coming from a hot water radiator (shown at left) or steam radiator then you need to see one of the two articles given immediately below:
Complete details about diagnosing and fixing cold radiators are found
at COLD HOT WATER BASEBOARD / RADIATOR
at COLD STEAM HEAT RADIATORS
(Dec 8, 2014) Rob said:
Hello,Having a problem in my basement heating system.Circulaing hot water with seperate t stat and pump for this area. Baseboard. so the problem is that the system piping gets hot and the basement remains warm even though the basement stat is off or set very low.
There are 2 other zones(pumps) on the boiler.My thinking id that there might be some kind of flow though this area from one of the other zones.Rhanks in advance for your help Rob email@example.com
Check if the circulator is a separate pump for this zone then you don't have a zone valve.
There may be a flow-control valve that is stuck open or manually opened, letting hot water circulate by convection or when other pumps are running.
(Dec 9, 2014) Anonymous said:
thanks for your quick response.Yes the circulator only serves this area.There are no zone control valves in the system.There are no check valves either
(Dec 12, 2014) Missy said:
I have fin baseboard heat(building built in 1974) in an apartment. The dining room bb heater is not working at all, the rest are working fine. Can I make an adjustment on this particular model to get it working and how?
Missy If the baseboard is air-bound it won't get hot - to read about easy homeowner repairs
(Dec 18, 2014) Kim Bogert said:
I have a horrible smell coming from a baseboard. The smell is strongest after bleeding the lines. Any idea what can be causing it?
Kim during bleeding of air in a hydronic heating system, air bled from a hot water heating system can be stinky but the odor should quickly dissipate and not return. That's normal.
(Jan 7, 2015) Anonymous said:
I don't have heat in the first 3 rooms where the water comes up to my baseboard, but I do have heat to the last 2 rooms at the end where in returns. How does that happen? It is cold out. Could there be a blockage and where? And how am I getting heat to the end of the system?
see AIRBOUND HEAT SYSTEM REPAIR - live link given below
2016/02/13 Felix said:
Hi my boiler has 2 zones, 1 is for my second floor apartment and the other is for the attic. The pipes past both zone valves are burning hot but the baseboards are not getting hot all. What might be wrong? Can you help?
Search InspectApedia for AIR BOUND RADIATORS as I suspect that the rads or in your case baseboards or piping to them are air bound
(Mar 3, 2015) Joe said:
We have a hotwater radiator system which is a combination of regular radiators with a couple of baseboard radiators. Last week we had a furnace problem and had to shut down and drain the system for repair. It is now fixed and everything is working EXCEPT one baseboard radiator.
The system has been bled several times. I can bleed the non-working baseboard radiator, and get hot water, but as soon as I stop bleeding the baseboard radiator cools back down. The rest of the radiators are working fine. Any thoughts?
Check for an air source that you've not found in the piping system or for incomplete system air removal.
(Mar 12, 2015) Doreen Corn said:
I keep smelling a burning smell in my baseboards..I have vaccum them , what is making that burning smell throughout my home, and who should i call?
(Mar 14, 2015) Mark said:
Hope someone can answer Joe and Doreen's questions (and mine). Here's mine: My mom thinks if you open the movable cover on her baseboard hot water radiators she'll get more heat.
I figure they were made such that when you keep the cover as it should be (practically closed, about 1/4 to 1/2 inch open from the side piece), this allows heat to build, and so more heat is generated. Any confirmation/thoughts on this? Thanks!
Doreen and Mark:
there's nothing combustible on the baseboards themselves: copper, aluminum, steel components make up the unit. Check for a spill or for something that has fallen into the baseboard unit.
Unless the smelly baseboards are actually leaking, the smell is most likely from something that is being heated such as a spill on the baseboards or nearby, or paint or wall paneling or even something Iin the wall or floor cavity near the baseboards. Search InspectAPedia for. SMELL PATCH TEST to see a low cost method that might help pinpoint the source.
Opening the hinged louver along the top of a heating baseboard increases the heat output by permitting more air to circulate through the unit, entering at the bottom, exiting at the top, moved by convection.
Closing the louvers along the top outlet of a heating baseboard will reduce the heat output as it slows convective air movement across the finned tubing of the baseboard.
Your mom is right.
The heat is generated at the boiler, not in the baseboards.
You are right that if you closed the louver the baseboard piping would feel hotter. But that's because you are no longer cooling it by moving room air across it. It's cooler because it's not sending heat into the room.
(Mar 15, 2015) Jeff D. said:
I have baseboard, hot water, furnace heating and shortly after my heating system turns itself off I hear a loud banging noise that comes from the last convector in the loop. I'm guessing that its bound up air but I frequently bleed the air from this last convector yet I still hear this banging noise. What else can it be?
You should not have to be frequently bleeding air pit of a baseboard. Either there is air left in the system that finds its way to the baseboard or there is a leak to find and fix.
A loud bang may be water hammer caused when a circulator of zone valve closes. InspectAPedia has articles on BANGING PIPES and also on WATER HAMMER that offer solutions. Try the search function above.
Ask your heating company for some diagnostic help, banging pipes can ultimately be unsafe as it can cause relief valve leaks.
(Mar 21, 2015) Jerry Gray said:
I have a house with the baseboard hot water heat from an oil boiler furnance. The house run out of oil and the house had no heat. Leaks started throughout the baseboards for the circulating hot water heat.
Each time the repairs are made the there are more leaks each time the boiler is fired up. What can we do to solve the problem?
We need to start by finding out what is causing the leaks - an accurate diagnosis: if the problem is due to freezing pipes then one they're repaired you may want to use an antifreeze in the heating system. If the leaks are due to corroded piping then all of that will need replacement. If the leaks are due to poor workmanship the solution to that is apparent in the saying.
Keep in mind that heating baseboard copper pipes are thin-wall; if your heating system water is corrosive that could be the problem.
(Mar 22, 2015) Michele said:
I live in an apartment and suddenly my electric bill has doubled when I called ComEd they said that I must be using more heat - when I told them the building has hot water baseboard heat (a fixed fee paid for seperately) ComEd said that there is an electrically powered blower to push the heat into my apartment - REALLY?
I don't know what the heck your Con-Ed phone contact is thinking about.
There are indeed electrically operated circulator pumps and if your heat was from a water-to-air heating convector that unit would have an electric blower fan but geez you told them you had hot water heat.
You need an on-site electrician with an ammeter if you want to see what circuits are drawing unusual current, or you can experiment by turning off circuits and watching your electric meter spin.
(Mar 29, 2015) Joanncull said:
This is a problem with a hot water baseboard heating system with a gas furnace. I have hot water(so the boiler is working) and I can hear the water circulating through the baseboards in all zones, but they aren't heating up?
I'm stumped and none of the tips I've found on-line address an issue like this.
Anyone have any ideas?
At More Reading just above
AIR-BOUND HEATING SYSTEMS - home
(Sept 10, 2015) Jamesd said:
We are looking to find a splice plate and a bracket/hook to hold the spliced baseboard heater cover in place.
We have a very old system (1960's) and can't find replacement parts. Where might the best place be to start our search?
I think our system is the same one that's in the first photo at the top of the page. I can see the hooks that hold the covers on and there is a splice plate as well. If anyone knows where to buy replacement parts for that system it would be welcome advice.
James the part you need is sold by heating and plumbing suppliers - it's used in normal baseboard installation to cover the butt joint of two baseboard covers.
(Sept 27, 2015) Jerry said:
our Parsonage has a two zone baseboard system. a thermostat 1st & 2nd floor our first floor is getting heat but the 2nd floor is not. at the heater one regulator is hot on one side but at the regulator that feeds the 2nd floor is cold on both sides of that regulator ?
AIR-BOUND HEATING SYSTEMS - home - found by searching Inspectapedia for those words.
(Oct 5, 2015) Adam said:
What are the requirements for insulation between the base board and exterior wall. I have some suspicion that their is no insulation between the baseboard and cinderblocks on my bottom level.
Typically the heating system relies on insulation inside the wall cavity. I agree that if heating baseboards are run along a solid masonry exterior wall then there will be some heat loss into the wall itself; A retrofit adding solid foam and drywall on the wall would improve matters but it is troublesome as the heating baseboards would have to be removed and reinstalled. Ugh.
(Oct 18, 2015) Nic said:
concrete condo, 2nd floor, baseboard heating has constant sound such as a forced air system. Also, sections always radiate heat even when thermostat is way low and not calling for heat. Rooms are 23-25C all the time even with windows open.
When turning up the heat on thermostat the system clicks a bit indicating heating and provides heat. The building contractor says noisy and hot because my unit is located near and above the boiler.
Do I need to live with this constant sound for the entire winter or can I have it capped and replace with my own separate electric baseboard heating that I can control and have some quieter operating system when in use.
See AIR-BOUND HEATING SYSTEMS - home
(Oct 19, 2015) Kevin said:
What can be done if your copper pipes are clogged, probably calcium buildup. What is the recommended procedure for cleaning out the pipes. There are 4 different zones in the system. I can isolate each zone if I need to. I have purchased a water softener so once everything is clean, hopefully it will stay that way.
Kevin it's possible to acid-wash scaled copper piping but finding that problem in heating pipes would be very odd as the heating system does not normally keep taking in new mineral-containing water. Scaling may not be the problem.
If you are asking about water supply piping (not heating piping) search InspectApedia for WATER PIPE SCALE REMOVAL for advice.
(Oct 30, 2015) Andrew said:
So I have a hot water fed cast iron baseboard heating system. One of the baseboard units knocks at night when the heat comes on. I bled it and every unit in the house but found no air in them, straight stream of water from each one. Any other thoughts?
Sure, Andrew, just search inspectApedia website (see the search box just above) for BANGING HEATING PIPES RADIATORS to see some useful diagnostics for both hot water and steam systems. I suspect a noisy valve or a problem that's keeping you from successfully getting all of the air out of the rad.
and also see AIR-BOUND HEATING SYSTEMS - home
(Nov 19, 2015) Leanne said:
How do you bleed a boiler heat lines
Leanne, see the details on air bleeder valves at AIR BLEEDER VALVES
(Dec 13, 2015) Sharon said:
I live in an,apt bldg, and the heat is always kept up to high, which our thermostats do not control.how can i safely cover my hot water registers to block out the heat??please help!!
First talk with building management as heating costs are involved.
Then awe details found n
by searching inspectapedia.com for the article titled RADIATOR BASEBOARD or CONVECTOR COVERS
(Jan 4, 2016) Christopher said:
To Sharon, wrap parts of the fins in aluminum foil. DON'T DAMAGE THE FINS. Do it bit by bit until you get the desired result. The foil stops the circulation of air through the fins.
Christopher & Sharon:
Christopher's idea is attractive but unless your heating baseboards have a removable front panel you won't have access to wrap the fins to reduce air movement through them and thus cut the heat output.
On a standard heating baseboard the convection current (warm air rises) that occurs up through the baseboard draws cool air from the floor up through the finned copper tubing where it is warmed before exiting at the top opening of the baseboard.
To reduce baseboard heat output in a room or area within a heating zone, a standard step that is effective to simply close the hinged top cover along the basboard. By interrupting the air movement you significantly reduce heat output. Blocking air air entry at the bottom opening of the baseboard ( such as by carpeting ) has the same effect.
(Dec 31, 2015) Sal said:
I had New hardwood floors installed. The cast iron baseboard was already in place. The cut the hardwood to fit under the legs and the baseboard is almost flush with the floors. No gap in between. Is this ok? Will the heat of the baseboard damage that section of the wood due to constant high temperatures?
If you close off the space between the bottom of the heating baseboard and the top of the floor you will reduce the heat output from the baseboard as you interrupt convection air currents that are a basic part of baseboard design and operation. The result may be a room that's too cool, longer time to heat the room, or higher heating bills.
(Jan 4, 2016) Christopher said:
I have a two zone baseboard oil burning system. Burner starts and runs fine. The basement zone works fine. Upstairs i have replaced the thermostat and circulating pump. It seems like the pump is not getting the call for heat. Is there something between the thermostat and circulating pump i can check?
Please see CIRCULATOR PUMPS & RELAYS - home
Christopher: if your upstairs heating zone is not working check
1. that the thermostat is set above room temp and thus is calling for heat
2. that the circulator pump runs for that zone, or if zone valves are used, that the zone valve opens
If both 1 & 2 are working properly then the system is probably airbound - search InspectApedia for AIRBOUND HEATING SYSTEM to see how to diagnose and repair that problem.
(Jan 16, 2016) Anonymous said:
The hot water baseboard registers are staying hot eventhough the thermostat is turned off. New thermostat installed but problem still exsists. Usually you can head the water flow in and out but now you can't.
(Feb 23, 2016) New maintaince man said:
I have an apartment with baseboard water heat, only the heat won't turn off. I turned the thermostat off but you can still heat the water rushing through the pipes which are hot. I was told to check the wire running from the thermostat to the baseboard but I don't know what to look for.
(Jan 22, 2016) anonymous said:
Does the thermostat control the baseboard heating.
(Jan 22, 2016) Anonymous said:
Should heat be coming from the baseboard if the thermostat is turned all the way down.
2016/04/11 Robert said:
Informative site - thank you!
I live in a condo with a hot water heating baseboards. Heat in the summer months is always a big problem in the unit, getting roasting hot, and I notice that the heating baseboards are quite warm to the touch (although not scaldingly so - like traditional radiators can be).
The heat is on the middle section of the baseboad unit that has the radiator apparatus (metal sheets), and the baseboard is not hot where the copper piping is on either side of that.
This situation exists despite the fact that the thermometor is set to its lowest, and the baseboards are admittedly not pushing air out when the thermometer is set at its coldest.
Is this normal? Is there a way for me to cool down the baseboards further, so that they're cool to the touch, at least in summer ?
If you are sure that the circulator pump itself is not running, then the most likely explanation of the problem you describe is that a flow control valve or check valve above or near your boiler has been manually left in the open position or has been stuck open. The results of this condition is that hot water will circulate out of the boiler by convection even if the circulator pump itself is not running.
If the thermostat is set below room temperature, the heating system should stop sending heat - you may need to wait for the baseboard to cool down; if after 30 minutes it's still hot then heat is still circulating: there is then probably a problem with the zone control, thermostat wiring, or a check valve in the system.
New M. Please search InspectApedia.com for HEAT WON'T TURN OFF to see some specific diagnostic suggestions.
To check for a bad thermostat, just disconnect the thermostat wires at the boiler end of the thermostat circuit. That'd be at a main aquastat control or at a circulator relay. You'll recognize the thermostat wires. Follow them. Disconnecting them at the boiler end will eliminate possibilities of a bad thermostat or shorted thermostat wires. If the heat keeps running the problem is at the boiler controls.
Heat can also circulate when the circulator is off if the FLOW CONTROL VALVE (Search InspectApedia for CHECK VALVES, HEATING SYSTEM) is stuck open but that will usually give a much slower flow rate that wouldn't be likely to sound like water rushing.
If your thermostat is not calling for heat but the baseboards are hot, then either there is a control snafu or
- there is a valve or control at the boiler that's manually open or stuck in open; it could be a zone valve or a check valve at the boiler that is allowing hot water to circulate by natural convection even when the circulator pump itself is OFF. Your condo association is wasting heating fuel if this is the case. No it's not normal. But cooling down the baseboards at your end is not a good approach as the underlying problems of energy cost and waste continue.
Ask your condo association to get help from an experienced heating service tech to find which control or valve is open that should be closed.
Also see HEAT WON'T TURN OFF
(Jan 22, 2016) Ray said:
I am on the board of a six-story co-op in NYC. The Board requires anyone doing renovations involving their plumbing system to install shut-offs at all entry points to the apartment in order to allow servicing without impacting other share-owners.
Some Board members want to extend this to include manual shut-offs on entry and exit points for the hot-water baseboard radiator system. Is this a common practice? Are there any potential operational or maintenance issues?
I do not think that's a common practice. Also, depending on how the heating piping and zones are installed shutting off a units heat could shut off that of others too. Opinion,
I wouldn't bother.
(Jan 29, 2016) Gerry said:
Some of our baseboard vents keep closing on their own. Are there clips I can use to keep them open?
If you refer to the louvered vent along the top of a baseboard, try bending the hinge opening at the end of the vent to tighten it on its rotating pin
If you are referring to air purging vents on the heating piping,
There are two types of vents; automatic ones that include a float and vent if air is present, and manual ones that are manually opened to bleed air. The latter are normally left screwed shut. The former open and close automatically. The screw cap on the automatic vent should be left loose. If the screw cap is clogging with debris the vent may need replacement.
(Feb 14, 2016) Alex said:
Hi - We just bought an old farmhouse in New England. We have hot water baseboard heat and woodstove. I've been keeping the thermostat at 70 degrees and yet the tiny old rooms don't get higher than 55 degrees unless I'm cranking the woodstove.
I'm not even sure how to tackle this problem - it could be my furnace (though that seemed to be in good shape when inspected twice in the last 6 months - looks like it hadn't been cleaned in many years, but we had it serviced and were told it's in good shape),
it could be my thermostat (it's one of those really old round dial ones), maybe the baseboard to room ratio is not enough, or maybe our pipes are clogged (our water is acidic and the copper pipes are slowly corroding - we have plans to install a water neutralizer). How do I start to tackle this problem? I don't even know which kind of professional to call.
Take a look at your thermostat. If the room temperature is below the thermostat's set temperature then the heat should be running.
If the heat is running take a look at your baseboards. Feel for heat coming from them. If baseboards are cold or tepid then hot water is not circulating and repair is needed: perhaps to a circulator, control, or to remove air from the system piping.
If the baseboards are hot but the heating system cannot get the room temperature up to the thermostat set point, then your home is losing heat faster than your heating system can provide it.
In that case you need to improve the home's energy efficiency by finding and stopping drafts and perhaps adding insulation.
In any case it makes sense to have your heating boiler cleaned and tuned as that will reduce your heating cost.I'm guessing from your location that your heating fuel is oil. NO oil fired heating boiler will run properly nor efficiently if it does not receive an annual cleaning and tuneup. I've seen as much as a 25% reduction in heating cost from a cleanout alone.
Search InspectApedia for ENERGY SAVINGS PRIORITIES for more help.
(Feb 16, 2016) kathryn said:
We just moved into a townhouse with electrical baseboard heaters and one in our bathroom was replaced by an electrician (the heaters are 50+ years old) the one in my bedroom comes on when turned off it has a mind of its own.
They replaced the thermostat but it has continued to do this the electrician said something to the contracter about a valve malfunction or something he completely confused the contractor. What else could be causing this so I can be prepared when he comes in so I don't have to have him back a third time if whatever he does this time doesn't work
Kathryn the situation you described is unsafe, risking fire or shock. Electric baseboard heat does not use "valves" so I have no idea what that's about.
Electric heat is very simple: typically a resistance-type electric baseboard, running on 240V is powered through a line-voltage thermostat that basically acts as an on-off switch in response to the thermostat setting and room temperature.
I'd expect the electrician to confirm that the heater itself is undamaged and to track down a bad wire, connection, or thermostat.
Search InspectApedia.com for ELECTRIC BASEBOARD HEAT INSTALL to read details.
(Apr 2, 2016) D Munro said:
Can you send information on filter covers for electric baseboard heaters - where to find them, sizes and price list? I have seen them advertised at one time online, but haven't found them again since. Thanks very much! Here's my email address: firstname.lastname@example.org (The landlord will supply them if I can find them again.)
I'm not sure what you want nor what sort of filters are used on electric heating baseboards - that's not something I've seen.
(Apr 3, 2016) Jerry said:
Soot coming from my oil baseboard heaters. How do I remedy this problem
Your hot water heating baseboards contain water; they won't emit soot. But dust, including sooty dust, can accumulate on the fins and tubing inside the baseboard. *Careful* vacuuming with the baseboard covers off, using a soft brush, can clean the fins and tubing, but you might want to look further for a soot source in your home.
Start by checking that your oil burner is working properly - ask for service if it's smoky, rumbling, noisy, smelly, or if you have gone more than a year without service.
Continue reading at AIR-BOUND HEATING SYSTEMS or select a topic from closely-related articles below, or see our complete INDEX to RELATED ARTICLES below.
Or see AIR BLEEDER VALVES for how to find and operate those cute little controls on baseboards (or radiators)
Or see DIAGNOSE & FIX HEATING PROBLEMS-BOILER if the boiler is just not working like it should
Or see these
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