Water pressure in Boiler

Discussion in 'Plumbers' Talk' started by koolpc, Oct 14, 2015.

  1. koolpc

    koolpc Super Member

    Guys, i topped up the pressure in my boiler (Worcester 28 CDi) about a bar to 1.5 yesterday as it has slowly been going down. This has happened constantly as every few months i have to top it up a bar. (6 Years)

    Thing is, the pressure has gone back down to where it was yesterday! It was .5bar and i topped it up to 1.5. Came home today it was back down to .5bar.

    I have checked all rads and all dry.

    Pressure relief that goes outside is and has always been bone dry!

    Big problem i have is that all the piping is under the floors (Suspended floors in a Bungalow).

    Now, i do have Central heating cover with BG. Anyone know where i stand with that?

    A plumber i know did put some stuff in the system a long time ago that is supposed to seal any tiny air leaks but i have still had to top up every few months.

    What can i do as i dont fancy taking all the floors up as i do have some access below but it is limited to the bathroom as there are brick supporting walls under the floors!!! No through access to every room! Help!
     
  2. tore81

    tore81 Screwfix Select

    Have you checked the bleed valves on the rads that they are tight.
     
  3. tore81

    tore81 Screwfix Select

    Also there is normally two valves on the Worcester boilers. To fill up the pressure.
     
  4. Top it up run the heating for fifteen minutes and then re-check the pressure relief I went to one today which was bone dry outside because of the breeze, I ran the heating and fifteen minutes later it started p1ssing out.
     
  5. koolpc

    koolpc Super Member

    Guys, bone dry!

    Just one place to top up on my boiler as far as i can see.

    Where do i stand if i call British Gas out?
     
  6. Dave does Gas

    Dave does Gas Screwfix Select

    If you have a contract with them and are paying for breakdown cover then you have every right to call them. The main exclusion they try and use is sludge in the system and this does not sound sludge related.
    Have a read through your BG paperwork check the small print but this sounds like a mechanical failure to me and it what your paying them for.
    One good way to test if it is the heating side, is to top the pressure up to 1.5 bar, then isolate the heating flow and return under the boiler. At no stage now should the heating be run. Just use it for hot water. 24 hours later check the gauge if there is no drop then no fault on the boiler, likewise if it has dropped fault is on the boiler. Now open both flow and return valves and check for a drop. Usually if there is a leak on the heating circuit it will drop instantly.
     
  7. koolpc

    koolpc Super Member

    Would BG be willing to rip up floors to get to the pipes? Is that included in the contract?
     
  8. koolpc

    koolpc Super Member

    If it was a faulty boiler, where is the water going? Must be a leak somewhere? Nothing coming out of pipe going to the outside as that is always bone dry.
     
  9. Dave does Gas

    Dave does Gas Screwfix Select

    You can either try this tried and tested method of proving its eiither the boiler or the cuircit or not, totally up to you. You came on here asking for advice we have given you some.
    You either call BG and get your moneys worth or you continue to try and resolve it yourself. Just because its not discharging via the PRV does not mean its not on the boiler, you could have a faulty heat exchanger and the water is going down the condensate drain. The method I have outlined eliminates one or the other.
     
  10. I agree with Dave.
    What does it cost to get your BG guys out?
    I would always advise that unless you are a competent person then leave it to the professionals
     
    Dave does Gas likes this.
  11. koolpc

    koolpc Super Member

    I dont have a clue when it comes to boilers. The needle has not dropped now. It is stable at just over .75 bar. I thank you for one way to test boiler but i am not sure what is what under the boiler!

    What is the minimum i should have the pressure at?
     
  12. Dave does Gas

    Dave does Gas Screwfix Select

    You have an insurance policy with BG just use it.
     
  13. Hi Koolpc.

    Step one: read through your policy and see whether it covers your whole system, or chust the boiler. Are the rads etc included?

    Step two: if the answer to Step one is 'yes', then proceed no further on here - contact BG post haste. If it's "Blugger, it only covers the actual boiler...", then proceed to Step three.

    Step three: Post a photo of the underside of your boiler on here, showing all the pipes as they exit your boiler.

    Step four: There is no Step four at the moment, so stop reading this **** and go back to the beginning.
     
  14. joinerjohn1

    joinerjohn1 Screwfix Select

    Problem with BG is,, they'll send a salesman round (claiming he's an "engineer") He'll condemn the boiler telling you, that you do indeed need a new one. Or,,, "They can't get the parts needed." Bloody con artists. ;);)
     
  15. Rulland

    Rulland Screwfix Select

    And they also do the same with electrics, "Your consumer unit doesn't meet regs, we can change it for a grand".
     
  16. koolpc

    koolpc Super Member

    Only had a service 2 months ago. Told them about pressure dropping. Guy said its normal. I have cover for Boiler and rads etc.
     
  17. Rulland

    Rulland Screwfix Select

    There ya go, trying to get out of it already!.
     
  18. koolpc

    koolpc Super Member

    Pressure has stayed the same since i started this thread!
     
  19. koolpc

    koolpc Super Member

    Topped up system again yesterday and called BG too.

    Pressure dropped back down again today.

    Gas guy came and said leak in pipe system. Obviously he was not prepared to lift floors! He put inhibitor in system to find leak. I said what about expansion vessel? He said no that should be ok. He looked at it thats all. Then, he put heating on and the pressure was rising too much!!! Over 3 and tiny drop of water came out of pipe outside. Bingo!!! Problem found i think.

    He has pumped up Expansion vessel now and see how that goes. Could be faulty
     
  20. Thanks for the update. Interesting... :)

    If your pressure has been regularly going up to 3 bar when hot, then that will happily also explain the loss of pressure you've been having.

    'Cos when the pressure hits ~3 bar, your safety valve opens to dump the excess water (due to expansion when hot), and then when your system cools down again the pressure will fall to below the starting point ('cos some of the system water has been lost).

    You have then been topping the system pressure back up to 1 bar, turning on the boiler which raises the pressure to 3 bar which dumps the excess, and then when it cools down the pressure falls to below 1 bar.

    You then top up the system back up to 1 bar, turn on the b...

    It's called 'a viscous circle' (yes, I know what I said... :p )

    It'll be good news if it was all down to a de-pressurised exp vessel.

    Keep us posted :)
     

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