The gauge on my Central Heating Boiler appears to have gone very high 3.5bar..... Do I have a problem, and how do I sort it..... Normally it used to sit around 1bar. Only just noticed it, and it goes up to around 4bar when it switches the heating on for the radiators, which is at the top of the scale.


Its a Gloworm Swift Flow Model.........(For those in the know.... )

 

have you topped up the tank? is it automatic or manual fill?

i would drain the system before any damage/leaks occur

BTW am only an apprentice

 

SCOTTP: Thanks for that, I haven't touched it, and its been working ok (And still appears to be) since new. Don't know if it's automatic or manual fill.

I know nothing about them, except that the pressure seems much higher than normal (It normally operated around 1bar)

 

If this is a sealed system it could be the filling loop is passing/open, you need to make sure the filling loop is closed (The filling loop is a braided piece of hose usually located near the boiler)

 

if it is auto fill there is a problem with the valve meaning it has filled itself up. I have known of system leak well below 3.5 bar - drain it ASAP

you wont get much heat into the system at that sort of pressure, a common misconception is: more pressure = more heat. it is the total opposite (i am not saying you have done this personally)

if its manual fill there should be some sort of tap or a filling loop so you can top it up,
if it has a loop there is no way any more water could get into the system, meaning there is another problem, maybe a pressure release valve fault??

To drain down there should be a valve like this


put a hose pipe on it and then open the valve. MAKE SURE THE OTHER END IS DOWN A DRAIN

Scott

 

right things to check
1st make sure the fill pipe is shut and remove it ( the hoze part ) and see if any water is leaking from it, if that is ok

2nd when cold make sure the level is on about 1

3rd you will have an expanshion vessel ( built in to boiler ) this has a tyre valve on top of it check the pressure on this as if it is 0 you will not have any room for the system to expand in to, if so look at your boiler manual to see what to pump it up to ( use a bike pump ) probley about 0.5 bar

hope this helps

 

valve on filling loop is a favourite,prob either passing or been caught and turned on slightly,assuming the loop has been left connected of course

 

mines is rattling is little bag off at the moment!! quite a modern house (well mid 80s) with microbore piping

seems to hit some resonance or something and vibrates the pipes. around the pump in the airing cupboard I think, seems worse.
only if been on for ages?

sorry for hijacking but thought whilst you were all there lol

 

Thanks Guys...........Will do it tomorrow and let you know how I get on.

Many Thanks.

 

OK....Found the fill pipe (Braided Hose leading from undersink water mains)...It was very slightly open and a very small jet of water was constantly coming out when I disconnected the Braided Hose. Now i've turned it of (just a very slight movement on the tap) and the supply is now totally closed.


What now.........???? Lol

According to user manual.... Gauge should be reading 0.8 bar

 

2 choices mate either find the pressure relief valve, normally at back of boiler and normally red and release pressure or drain from a drain off, usually on pipe going to a rad, you want about a bar/ bar and half when system is cold, also remove that flexi pipe so it dont happen again

 

Can I drain/reduce the pressure from one of the rads.....????

 

what you need to do jim is drain the pressure off the system until the gauge reads zero.

then get a good look at the top of the boiler for red round vessel with the car tyre valve.

with the drain for the CH still open pump the red vessel up to 1 bar.(the pressure gauge onthe boiler might move at first but just keep lettingthe water drain out until the vessel is at one and the gauge is at zero.)

if you are successful close the crain and top presure up to 1.5 bar on gauge.

turn heat on max and you should only see a slight movement maybe up to 2 bar on the gauge.

if this process doesnt work its time to call in the pros mate.

 

Can I drain/reduce the pressure from one of the rads.....????

 

can get messy, if you have no drain points look in manual for pressure releif valve and release it that way

 

Sorry to hi jack ur topic but its kinda the same subject.
A few weeks ago, i rang up and reported a problem with one of my radiators.. they came out n looked at it and said the valve is broken (cant remember what the exact name of it was) could of been timer? Oh i dont know
Just wondering is it a expensive thing to buy an fix?
Could i do it myself?? Ojk!!

 

Yep.... I have a drain tap on one of the radiators.......Can I use this to reduce the pressure/drain.....?

 

if just one rad you probably mean trv, means draining down whole system, change valve and refill, if not sure dont try could end up getting very messy and rather expensive

 

yeah mate stick hose on it and other end of hose down a drain or somewhere and open the valve

 

yes but will take ages..

have a look outside at ground level for a drain cock...

there are other ways of doing it but involves removing casing from boiler etc.

what has more than likely happend is that the red vessel(expansion) has lost its charge.(normal over time)

this controls the water pressure as it heats up.

the vessels can burst mate which means your "proper fooked"

 

most of the stuff with drainng and filling systems isnt rocket science but can do alot of damage if you get it wrong.

best to call someone that knows what they are doing

 

Thanks Guys,

I owe you a couple of beers I think.....

Will drain it just a bit, to try and reduce the pressure, and then get a service booked on it tomorrow.

Cheers Again

Jim

 

if you can reduce the pressure jim it should continue to give you heat.

the PRV(pressure relielf valve) is designed to open at 3 bar so you are safe enough mate.

also worth turning the thermostat down abit to give the boiler an easier time until its fixed.

might help reduce pressure too

 

Opened drain tap on one of the radiators, let about two liters of water out...............and gauge now reading 1bar............ Did I do the right thing ??????

 

for the time being yes mate

 

try the procedure mentioned above inthe morning.

make sure the boiler is switched off while you do it.

 

And still got hot water and rads working.........

 

everything should stay working unless the pressure drops to zero.

best to get it looked at sooner rather than later as you dont want to introduce too much untreated water into the system.

 

Thanks again guys, all appears ok at the moment and the pressure is down to a max (When Heating) of 1.7bar, and settles just over 1bar when it's off.

I'll get it serviced this week though.

Many Many Thanks

 

no worries jim