Noticed some changes? You can read all about the improvements we've made on the Forum in our latest announcement. We also have a new set of Forum rules so please take the time to give them a read and familiarise yourself.

Stuck Lockshield Valve on radiator

edited 30 November -1 at 1:00AM in In my home (includes DIY) MoneySaving
8 replies 2.9K views
turboturbo Forumite
171 Posts
We had a new boiler in Summer 2018 and the system was power flushed. The radiator in the living room is slightly warm at the top only. No air in radiator. I've checked the TRV and it's not jammed. We have had the radiator for 14 years. The pipe that leads to the lockshield valve is warm. I've tried all types of spanners/pliers but have been unable to open the valve. Access is not good as the lockshield valve end is about three inches from the wall. I've looked at lots of videos that show how to turn the lockshield valve on or off. It's a square spindle on the lockshield valve. It's a 2m long radiator. Is there anything I can do to fix this.?

Replies

  • edited 30 November 2019 at 3:31PM
    neilmclneilmcl Forumite
    18.1K Posts
    Part of the Furniture 10,000 Posts Name Dropper
    ✭✭✭✭✭
    edited 30 November 2019 at 3:31PM
    Try a bit of wd40 down the spindle and leave for a bit before trying again with a pair of adjustables. Remember, it's anti-clockwise to open.

    Also, you say you've checked the TRV, have you actually took the TRV head off to see if the pin on the valve is stuck down.

    TBH, if the lockshield is seized then generally they're seized in either closed or fully open position and if you getting heat in the rad then it's probably already fully open which would suggest the problem is further back down the line and you need to balance the other rads, starting with the ones upstairs.
  • turboturbo Forumite
    171 Posts
    Thank you neilmcl. I did take off the head of the TRV and the pin was moving.
    I will do some reading about balancing radiators. My husband has a multimeter. Is that suitable for balancing radiators.? I have tried switching all radiators off apart from the living room one and that did not seem to make much difference. Thanks again for your reply.
  • EssexExileEssexExile Forumite
    5.2K Posts
    Sixth Anniversary 1,000 Posts Name Dropper Photogenic
    ✭✭✭✭
    turbo wrote: »
    Thank you neilmcl. I did take off the head of the TRV and the pin was moving.
    I will do some reading about balancing radiators. My husband has a multimeter. Is that suitable for balancing radiators.? I have tried switching all radiators off apart from the living room one and that did not seem to make much difference. Thanks again for your reply.

    If it still didn't heat up with all the others turned off then one of the valves is off or there is a blockage.
    Tall, dark & handsome. Well two out of three ain't bad.
  • turbo wrote: »
    Thank you neilmcl. I did take off the head of the TRV and the pin was moving.
    I will do some reading about balancing radiators. My husband has a multimeter. Is that suitable for balancing radiators.? I have tried switching all radiators off apart from the living room one and that did not seem to make much difference. Thanks again for your reply.

    A multimeter won't help, read up on balancing the system or there are some good videos on utube. Plumberparts and skill builder, Roger Bisby or something similar are two good plumbers on there.
  • BelenusBelenus Forumite
    1.7K Posts
    Sixth Anniversary 1,000 Posts Name Dropper
    ✭✭✭
    turbo wrote: »
    Thank you neilmcl. I did take off the head of the TRV and the pin was moving...

    The pin may well be free with the TRV head removed but the TRV head may be stuck in the closed position.

    That has happened a few times with our Myson TRVs.

    Leave the head off and see if the radiator warms up.
    A man walked into a car showroom.
    He said to the salesman, “My wife would like to talk to you about the Volkswagen Golf in the showroom window.”
    Salesman said, “We haven't got a Volkswagen Golf in the showroom window.”
    The man replied, “You have now mate".
  • turboturbo Forumite
    171 Posts
    Thank you Essex Exile, that is useful information.
    Thanks George333 for those plumber video recommendations.
    Thank you Belenus. I will try that.
  • BelenusBelenus Forumite
    1.7K Posts
    Sixth Anniversary 1,000 Posts Name Dropper
    ✭✭✭
    Belenus wrote: »
    ..Leave the head off and see if the radiator warms up.
    turbo wrote: »
    ...Thank you Belenus. I will try that.

    If it does prove to be a new head you don't need to change the valve.

    Just buy a new matching head or, if not separately available, buy a new TRV unit but just use the new head on the existing valve and keep the new valve for possible future use.
    A man walked into a car showroom.
    He said to the salesman, “My wife would like to talk to you about the Volkswagen Golf in the showroom window.”
    Salesman said, “We haven't got a Volkswagen Golf in the showroom window.”
    The man replied, “You have now mate".
  • turboturbo Forumite
    171 Posts
    Hello Belenus, I've taken the head off the TRV and it hasn't made any difference to the lack of heat in the radiator.
This discussion has been closed.