Baxi Gas Boiler-Pressure Problem

L

LimerickMan

Registered User
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Hi all,
The pressure keeps dropping on my Baxi system gas boiler (new house/heating system - 1 yr old). The manufacturer recommends maintaining the pressure guage between 1 and 2 bars but it keeps dropping below 1. The plumber (who installed the system) showed me how to increase the pressure (open a valve by turning a screw on one of the pipes feeding the boiler for a few seconds). He claims it's normal for this to happen but I have to top it up nearly every week.
Any ideas what the problem might be and what can I do?
Thanks!
 
Hello, it is OK to top a heating system up a couple times a year, as all pressurizes heating systems leak microscopically, but if you are refilling every week you are going to lose any inhibitor in the heating system or dilute it, which over time will lead to a sludged system, there is a couple of things you can do, first walk around the system and have a good look on all the joints checking for water, secondly put a bottle over your discharge pipe outside to check if you have any water passing your 3 bar pressure relief valve within the boiler to outside, lastly if you can't determine if the leak is on the system or at the boiler turn off the boiler isolation valves leave it a couple of days. then check if the boiler is still pressurized if it is boiler is OK open isolation valves , if pressure drops the leak is on your system pipe work and you will have to start isolating your system circuits to identify area of leak, good luck. Gary
 
Same topic Gary. I had a similar problem with my system. the (2nd) plumber thought the leak was within my tank and installed a new one. He also put in an automatic top up thingie. All went well for a couple of years until 2 days ago, my boiler failed. It was corroded to hell and basically fell apart. It had been serviced 18 months prior.

My question is does the auto top up hide any problem with leaks? As I have to get a new boiler asap will the same thing happen eventually? One other symptom was brown ish water from the hot water in winter only (with heating on) This stopped for the most part with the new tank..

Bit worried to be honest. Have found the plumbers I called out not interested in the bigger problem....
 
Hello, i hate auto fillers with a passion as they can be fitted to hide a leak in a sealed system, this will also mean the loss or dilution of any inhabiter in the system water to protect from the build up of sludge or other contaminants which will shorten the life span of a modern boiler,before you have a new boiler fitted, ask the plumber to have a look at the water in your rads for any contamination to decide how you need to flush your system. It is possible if the coil, which is inside of a hot water cylinder splits, heating system water can pass into the stored water in the cylinder which can show up as discoloration in the water at your hot tap and it sounds like if the brown water has gone then your old cylinder could be to blame.
I wouldn't worry to much, once the system is flushed you would be starting afresh and if you keep your inhibitor topped up you will be giving your boiler the best chance for a long life,Hope it helps, Gary.
 
Thanks for the reply Gary. Had an interesting conversion with my new plumber. He has agreed to swap the auto top up for a manual version so I can monitor the pressure drop myself. Hopefully I can then spot any leaks happening. I will get him to check the rads when he puts in the boiler also, I suppose thats the only real way to check any prior contamination. Any thing to protect my new shiny (expensive) boiler!

Just have to convince the insurance to pay out....hmmm tough one!
 
If you look at the sites for fernox ( ) or sentinel ( [broken link removed] ), you will find more information about problems with dirty system water. You may find you have minimal contamination and than the trick would be to keep it clean, if a system has the correct amount of inhibitor in and every 3-5 years it is topped up you will NEVER have the problems that go hand in hand with a sludged system.
 
Thanks Gary. I am properly educated now. Cost me thousands though, so I'll spread the word with the neighbours. The builder was a bit of a chancer!
 
Most system boilers come with a minimal pressure vessel that is often to small for the size of the system that it serves. Additional vessel capacity is appropriate in many cases.

By the time everyone has let a little air out of the vessel to see if there´s any in there it is depleted.

Air should only be released from a vessel by someone who has the means to put it back in.

Ask you plumber to study the boiler installation literature carefully.
 
Hi Plumber
My 18 year old natural gas, System Non Condensing boiler heating copper cylinder & radiators is giving trouble. Got heating installer to look at it. He advises replacing with the same system & a new Baxi Solo 3 boiler - cost €1900 incl VAT. Standard 3 bed terrace house - 18 years old. One bathroom, with bath & electric shower & downstairs toilet & wash basin - no en suite.
Any views on the price.
Also any views - should I go for -
1. System or Combi. Will change to Combi mean much new piping.
2. Condensing or Non Condensing.
 
In certain areas of the UK or Ireland mains water supply may sometimes be inadequate for a combination boiler to perform as it is intended.

Your Installer will be familiar with local water supply so it is probably best to take his advice. Also avoid using imported continental mixer taps ie those with the narrow flexible hoses. unless you are using pumped supplies.
I only give quotations for jobs that I am asked to do in south Dublin area
I would not comment on prices charged by other contractors.

Sorry about late reply
 
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Hi all,
I posted the original post here, I'm still waiting on the builders to send a plumber to look at this.
I recently noticed a short length of hose sticking out from the soffit and it's dripping water down the side of the house, by the looks of the wall I'd say this has been happening for some time, can't belive I didn't notice it before. I'm guessing the hose is some sort of overflow pipe from the water tank in the attic.
Could this possibly be connected to the water pressure problem in my heating system?
Thanks all.
 

its unlikely that these issues are connected.
If this is continuously dripping the get it seen to ASAP.

I had a similar problem, called by Bro-in-law, whos a plumber.
The reason for the problem wa sthe builders had closed the top of the water tank with a sheet of MDF. This had gotten wet (by condensation, as its covered in insulation). It had sagged in the middle, thus stopping the ball cock from closing properly so there was a continuous supply of water entering the tank. Luckly enough with 6 people in the house, the tank was being used very often so it didnt overflow, but that was a serious possibility.

my advice?? get it seen to straight away...
 
There is safety pressure valve on any central heating generally very close to the boiler itself (soemthign with a red plastic cap)
AFAIK, i can be activated manually for testing by turning it a quarter turn. This valve is suppossed to be contected to a hose in case system pressure goes to high.

Could it be a possibility that this valve be stuck open, hence poor pressure and water leaking outside?
 
I wouldn't advise testing a 3bar discharge valve as when you open it, you may find you can't close it, then you would have pressure issues.
 
Gary

I have the same problem with a Baxi combi. You say "It is possible if the coil, which is inside of a hot water cylinder splits, heating system water can pass into the stored water in the cylinder which can show up as discoloration in the water at your hot tap". I do not have a separate water cylinder but am I correct that there is a coil inside a combi boiler and this could have split? The symptoms that I see would suggest so; Symptom 1 = system loses pressure even if feeds to radiators are isolated (turned off), Symptom 2 = water from taps is often brown and murky. Thanks
 
in my first house i had that problem, th builder installed a valve slightly open to keep it fed,, seems to me that the continuos introduction of fresh water into a closed loop system will then allow in oxygen,, all adding up to corrosion later in time
 
my current boiler is cutting out every couple of minutes, i've had a plumber out to examine the problem yesterday (02.12.08) he's suggested the fan may be the problem and the approx cost would be 400 euro to replace this item. I have replaced the circuit boards twice in the last 5 years ( with different engineers) from what i remember these were costly items as well. The boiler is approx 12 years old. I've now decided on installing a new boiler and the plumber has recommended a 'baxi boiler megaflow system'. The boiler is situated in an outside brick shed and the supply and installation will cost 2200 euro. I have 12 radiators ( 4 bed house ) and the house is located in sth Dublin. Basically my question relates to the quality of the proposed new boiler, is it a quality product and is the price representative of market place.
kind regards
Niall
 
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