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We look at the most common symptoms of bad recirculating pump in this guide
One of the most common reasons why you may not be getting hot water from your system is a failed recirculating pump.
Unfortunately, it is not always easy to tell that the part has malfunctioned- and indeed many people do not know the symptoms of a bad recirculating pump.
So below we look at the most obvious symptoms of bad recirculating pump to help you tell when this critical pump has malfunctioned.
Symptoms of bad recirculating pump [how to tell if hot water recirculating pump is working]
When the recirculating pump has failed, you’re likely to notice the following signs:
Hot water is in the cold line
Normally, if you have a dedicated return line, you should get hot water coming out of hot water pipes.
And so if you are getting hot water in your cold pipes, then it could be due to a malfunctioning recirc pump.
Specifically, the fault means that hot and cold water are, at some point, mixing
Remember that the issue should not worry you if your system has no return line(hot water will typically be in the cold lines in this case).
Also, it is possible that the problem is arising due to a broken pressure balancing valve(this Video explains it well).
Longer wait timer for hot water
You probably know this: If you suddenly have to wait more minutes for hot water to emerge from your faucets and showerheads, then chances are your recirc pump is troubled.
Just to be clear, a wait time of over 90 seconds is going to see you wasting quite a lot of cold water, which potentially translates to a rapid increase in your water bill.
Water is seen around the pump
Check to see if water could be leaking from around your recirculating pump. If yes, the most probable culprit is a bad vent(which is pretty cheap).
So try to replace that part.
You might also note water run down your recirculating pump pipe.
The good thing is that this can be a very minor fix too(simply clean up any build up you see, wipe the area dry, and re-seal all the leaking joints)
The pump is making some strange noises
If your recirculating pump is rattling, the odds are there is air in there.
But it is not a goner (most of the time it isn’t)- simply see if you can open your grundfos pump vent plug then run the circulator (to vent the pump).
It’s worth mentioning that other recirculating pump models are designed with similar air bleeding mechanisms so check what your pump’s owners manual says about purging air.
Higher power bills
Another thing you could notice is a jump in your energy bills and that’s because your recirculator could be wasting more power when it’s bad.
How?
This happens when it starts to turn on many more times due to a fault including when no one needs hot water – remember it comes on whenever it detects cold water in there.
But do not be too fast to condemn the pump- it might not have been installed the right way so inspect how it is installed.
4 Common recirculating pump problems and hot water recirculating pump troubleshooting
A dying recirculating pump can catch you off guard and you now know the tell-tale signs you should be on the lookout for.
Let us now discuss some of the most common hot water recirculation system problems and possible solutions for each of these issues (you might be a super DIY-oriented person):
Recirculating pump won’t start
If your pump won’t kick in after powering on, first verify if there’s power.
Now, if the power supply is okay, check the electrical wiring to it- it may be defective at some point.
A less common cause of starting issues is wrong installation.
So check and remove the pump then refit it correctly- call a pro., if necessary.
Hot water recirculating pump constantly running
Your recirc pump is probably constantly running because the return temperature is not really getting up -to the point it is set to- because there’s significant heat loss along the supply and return pipes(from poor/no insulation).
So without proper insulation -on your hot water piping-it is inevitably going to end up running 24/7 to compensate for the drop in temps.
That means you need to insulate the hot water piping appropriately.
Also see if you can install an aquastat(on the return leg) to control the pump- this will be shutting it off once the return temp reaches the set temperature.
Lastly, you may consider putting a timer to again control the recirculation pump during specific hours (during the day).
That way, your pump will only run in the morning/evenings when people are home(to cut down on energy loss).
There is no hot water!
When your circulation pump is on but it’s not pumping water through your plumbing, it’s the propeller or another component that’s stuck.
That being the case, you can just tap the pump gently to try and free up any part that has become stuck.
Your pump is leaking
If water is leaking from your circulating pump, it may be because there is a loose joint in your plumbing that you had failed to notice.
Firstly, check your piping to see if you can point out the leakage and tighten any loose joints using an adjustable spanner.
What if the leaking does not stop?
Well, should leaking continue, take a look at the recircle. pump itself since some parts may have corroded.
Now, if extensive corrosion is causing the leakage, you may have to replace your pump.
Recirculating pump is too noisy
If your circulating pump makes ears-splitting sounds, the first suspect should be an airlock in the pump. (We already said that an airlock can stall these pumps)
So try to bleed it (refer to your owners manual for complete instructions).
Quick Tip: If the noise remains, you may want to see if there’s a bad bearing inside. It could also be that your pump was not properly sized (it is either not powerful enough or excessively powerful). Contact a pro. here (there are no easy fixes here).
How long do hot water recirculating pumps last?
Well, depending on how well you maintain it, your hot water recirculating pump can serve you dependably for anything between 10-15 years!how long do hot water recirculating pumps last
Symptoms of bad recirculating pump – recap
I hope that by understanding how your water system behaves when the hot recirculating pump is bad, you can quickly troubleshoot it and that you’ll have hot water coming out instantly again soon.
Good luck.
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