DIY - How To Repair A Leaking Radiator Valve
This article will guide you through the process of repairing a leaking radiator valve or lock shield. As we all know hiring professional tradesmen is an expensive business and it can be truly frustrating to be presented with a large bill after finding out that the job cost pennies to actually do and was simple enough to be done by yourself if only you'd have known how. I was faced with this particular issue earlier this week and after careful few hours of research (note that some webpages offering advice show a very expensive mistake that could cost you dearly), I spent a little under 10 minutes and a grand total of £1.25 (less than two US dollars) to fix this issue. As a bonus, this also fixed a long term problem with our boiler that has cost us two engineer visits and repair work without result (very expensive), obviously the leak had been there longer than we thought.
What You Need For This Project
The DIY plumbing tools required for this job are simple and many households will have these the items readily available.
You will need:
an adjustable spanner,
a pair of pipe grips or a stillson wrench,
a roll of PTFE thread seal tape.
It is vitally important that you not try this task without a pair of pipe grips or a similar tool. Doing so could well lead to damaging the radiator and requiring not only the hiring of a plumber, but also the replacement of a radiator; this mistake could turn a cheap and easy job into a messy and expensive disaster. Be careful, don't cut corners!
Diagnosing The Problem
This tutorial is designed to show you how to deal with a leak from either a standard manual radiator valve or a lock shield (a similar fitting to a valve, but without the control knob, which is fitted to the opposite side of the radiator from the control valve). This problem shows itself by a small amount of water trickling down the outside of the valve. When the part is examining (after drying) water will be seen to be coming through the centre of the fitting through the whole where the spindle sits. If the water is coming through in quantity under pressure, this is not a DIY job, call plumber.
Water coming from any other area on a radiator except those described in the above paragraph are not covered in this page; you will need to seek help elsewhere for these issues.
While the job itself is very simple, there are several things that can go wrong and so it is imperative that while you're doing this quick and simple task you are attentive to the job in hand. Make sure that you read the whole process through before you start the job; a print out or notes may be helpful as a reminder while you work.
1) Have a number of a local plumber to hand.
It is possible that you might discover during this job that the problem is more serious than you first thought or you may do something other than instructed and damage the system yourself, be prepared for things not being the way you thought they were.
2) Turn off the Radiator.
Working on a red hot radiator is never going to be a good idea, turn it off and allow it to cool down.
3) Remove the cap or radiator control knob/wheel and expose the spindle and the gland nut.
This is a brass nut with a brass rod coming through the middle of it, see photograph.
4) Firmly gripping the fixture with the pipe grips, slowly tighten the gland nut with the adjustable spanner to a maximum of a quarter turn.
You may wish to pad the grips to avoid scratching paintwork or a chromed fixture. Failure to use the grips here can result in strain being placed upon the main connecting joint between the valve and the radiator causing a leak which will require the radiator to be replaced, don't take shortcuts, they can be expensive. If the gland nut will not tighten, don't force it, or there is still seepage (wait a few moments to be sure) go on to step five.
5) Firmly gripping the fixture with the pipe grips, slowly loosen with the adjustable spanner and remove the gland nut.
You may wish to pad the grips to avoid scratching paintwork or a chromed fixture. Failure to use the grips here can result in strain being placed upon the main connecting joint between the valve and the radiator causing a leak which will require the radiator to be replaced, don't take shortcuts, they can be expensive. While doing this it is important that you pay attention to the gland nut, there should be very little increase in the amount of water coming out. If you find the flow of water or the pressure of the flow increasing noticeably, this is not a DIY problem, tighten the nut back up and call your plumber.
6) Take a small length of PTFE tape and twist it into a chord.
You will need no more than two or 3 inches of PTFE chord for this task, simply break off a suitable length of PTFE tape and twist both ends in opposite directions, you will have a chord of a suitable length for the task. It's always best to have too much rather than too little, if you not sure give it another inch or two if it's too long then there are always scissors, if it's too short throw it away and start again.
7) Wrap the PTFE chord around the spindle 4 or 5 times and push this down to the grommet at the base of the fixture.
You do not need a great deal of PTFE here, in fact too much may cause problems.
8) Firmly gripping the fixture with the pipe grips, slowly, with the adjustable spanner, replace and tighten the gland nut.
You may wish to pad the grips to avoid scratching paintwork or a chromed fixture. Failure to use the grips here can result in strain being placed upon the main connecting joint between the valve and the radiator causing a leak which will require the radiator to be replaced, don't take shortcuts, they can be expensive. Slowly and steadily is the key to this task, be certain not to over tighten the nut.
9) Replace the cap/wheel/knob, switch on the heating and observe the radiator for 1 - 2 hours to be certain that the problem is fixed.
This should have resolved the problem, as always with a DIY project if there is still a problem call professional plumber for help, you should have his number from step 1.