For the last 20 years or so, most people in the UK have not needed a hot water tap for their washing machine. So what should you do with yours? Just ignore it – or blank it off?
What should you do with the unused hot tap?
There are 4 options. Some may seem inconvenient, but there could be good reasons to consider them –
- Just forget about it and leave it where it is
- Cap it off with a blanking cap
- Remove tap and all pipework branching off from the main pipe
- Leave hot hose attached and regularly flush hot water through the unused pipework (my personal choice)
Leave everything as it is and do nothing
1: This is the easiest option, already taken by most people, who just stopped using the hot tap and forgot about it. For most people, it’s probably OK to do this…
However, when I found out that dangerous bacteria could build up inside the unused pipes, and contaminate the water supply, I became concerned (explained later…)
Fit a blanking cap to cap it off
2: If leaving everything as it is, but just no longer using the hot tap, you might want to fit a blanking cap to ensure no water can escape from it as it’s not connected to anything. You may be concerned that someone could inadvertently turn it on, causing water damage.
Or, depending on where the tap is situated, you might worry that it could get slightly knocked, and start dribbling water. This is especially true if the tap is inside a cupboard and has plastic levers to turn it on.
Don’t fit a blanking cap without understanding this entire article first
Buying a blanking cap for the old hot tap
If you decide to cap off the unused tap, you need a specific size of blanking cap. The size you require if you want to source one from a shop is – 3/4″ (which is around 19 mm). You could also buy it from Amazon (paid link) – Buy 3/4″ Brass blanking cap and washer
You should also be able to buy one from any plumbers merchant or DIY store. The cap should come with a rubber seal. If it doesn’t, try using the old seal from the hot water pipe.
You should consider removing the unused tap and pipework
3: When a water tap is not used any more, water ceases to flow through all the pipework that branches off from the main pipe to the tap. The water trapped inside becomes stagnant.
If conditions allow, bacteria and other microorganisms can grow inside that can break off and get into the rest of the water supply.
I did a lot of research about this issue, and became convinced that there could be a potential health issue for some people. (There’s a link at the bottom of this article to fully explain this).
Leave hot hose attached – and flush regularly
4: This is a solution if you are concerned about the potential growth of microorganisms and bacteria described in my companion article (link at end of this article) – but you don’t want to have unused pipework removed. It doesn’t need a plumber, and the hot tap is retained in case it’s ever needed again. You never know if hot and cold fill washing machines might return.
I’ve left my hot fill hose connected to the hot tap, but just hung up out of the way. I have a monthly reminder set up on my phone to run the hot water tap until piping hot water flows through it. This kills bacteria and replaces the stagnant water.
You could flush the hot water into a sink, a bucket, or the washing machine’s standpipe. The point is to have (60 degrees) hot water flowing through all the dead pipework. This should flush away stagnant water, and kill off and remove any microorganisms, or bacteria.
By the way, this option is easy for me. My washing machine is in the garage. It’s easy to access the hoses and standpipe. But it may not be practical for everyone. If it isn’t for you, then you’ll need to choose one of the other options.
How long do I run the hot water for? I usually do it for 30 seconds of hot water flow, but I’ve seen advice saying run for longer – and once a week! We all need to make an informed decision, which should be based on a proper understanding of the issue, and the configuration of our own plumbing setup.
If you believe there is a potential health risk, you should have the dead leg pipework removed properly. Read on for a much better understanding of how real this risk is for you, and your circumstances.
Is the dead leg health risk a genuinely serious issue?
Read my follow-up article, which explains the issue in full detail, so that you will be able to make an informed choice – potential health risks in not using old hot water tap.
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Thank you for the advice. The pipe dripped even after turning off the tap so I got one of these jobbies from the firm you suggested. It was delivered quickly and Hey Presto no more drips.
Tony
Good advice Kev, but no need to go hunting for old bike tire. When disconnecting old hose save rubber washer and reuse to seal 10p coin against fitting. For the avoidance of doubt washer goes between coin and fitting , not between coin and plastic screw on nut recovered from your old fill hose .Also works on redundant waste hose connections to sink waste etc.
Thank you so much. You are an amazingly generous person to share your knowledge for free, whilst a plumber would have charged me in excess of £100 (call out fee and unnecessary parts and obligatory cuppa). Thank you is not enough. But thank you.
I’ve just purchased a new washing machine and only has the cold water pipe. I closed the hot water tap off and it still has a small drip from the tap. Can I just fit a blanking cap or do I need a plumber to fit a new valve or close the pipe off??
Hello Robert. I understand your concern. As the cap has a rubber seal I would expect it to be OK especially as there is no real pressure, just a small drip. Keep an eye on it and check it regularly until it’s been on several weeks. If the tap is one with the red plastic levers though I would unscrew the plastic lever and try tweaking the valve shut more with some pliers, which may stop the drip altogether. Those type of taps commonly don’t close off 100% at times.
Hi Andy, Currys refused to fit my new washing machine friday, my 12+ yr old Hotpoint finally passed on :( but he had cold & hot, new one is just cold, but they refused to fit because I have NO taps on my pipes at all, the words he used were ‘broken off’??? hot & cold hoses were screwed on! I assumed that was the norm. Plumbers are quoting me 70 quid!
This is a housing assosiation place, am I right that it’s their responsibility to fit taps? Or is it easy for me to do myself?
Any advice gratefully received.
Damsel in distress! x
Hello Caroline. Unfortunately these retailers claim to “install” a washing machine but if there’s a single slight issue the “installers” refuse to do it. They will usually only screw the hose on and connect the drain hose as long as it’s dead easy to do. If there’s any awkwardness or difficulty they refuse. However, if there were no taps, that’s pretty rare and unusual. I can’t remember coming across such a thing. If there were no taps it means to disconnect the hoses you’d have to turn off the mains water, then drain all the hot water from the system to get the hot hose off. In such circumstances I can understand them saying they can’t do that. The terms and conditions usually say they will connect as long as it’s straight forward.
If there are taps, and they just didn’t look properly I’d be inclined to complain and get them back. I have two articles on installing a washing machine which you should read.
How to install washing machine
Install washing drain hose
Awww thank you for replying hun, I had no joy with the landlord, they don’t get involved in washing machines apparently, but they said taps aren’t essential so I went & got a cap this morning, but it still leaked, so I have a plumber coming over soon as I now have the water off. He’s charging 50 quid to cut pipe back a tad, put tap on & totally blank the hot off x
My cold water fill tap has broken. I thought I would be able to swap it for the red tap but it does not fit. My friend also gave me another black tap and that doesn’t fit either. I resorted to use pliers to switch the cold water on but can only partially turn the valve. There is a small trickle of water going into my washer but it is obviously not enough pressure. Is there anything else I can do myself before calling a plumber?
Babsie, hot and cold taps are identical apart from the colour of the levers or caps (red and blue). If the valve is stiff it needs replacing.They are known to seize up inside.
Can I use a self tapping cold water tap or do I need to get a plumber to put a complete new tap in for me?