Puma 80e pressure loss

[mlkey]

Hi all,

Long story but will try to keep it brief!

Recently our Puma 80e started making kettling noises. We called out the Direct Line people (who cover our boiler) and they said the heat exchanger was full of lime scale. Direct Line said this was not covered!

I then added Fernox DS40 to the system, and within an hour everything was working well. Within 4 hours, there was water pouring from the bottom of the boiler.

Direct Line let us down again so I fixed it myself... It was the 22mm isolating valves and an O ring on the CH water temp sensor all leaking.

Left the remainder of the DS40 in for the remaning time as per instructions. Drained, flushed lots and added the neutraliser for 2 hours.

Drained and flushed again, added Fernox Inhibitor. Everything was great.

Left the auto air valve on top of boiler open to remove last of air.

This was over a week ago!

I am having to top the boiler up every other day with around 0.5 bar pressure to maintain around 1.0 bar cold.

I have exhausted every avenue I can think of and cannot find any leaks anywhere, yet that amount of pressure is more than just a few drops??

I have checked:

The pressure relief valve - it did stick when I used it to drain the boiler, and was the prime suspect. I cable tied a clear plastic bag over the pipe - not a drop has entered the bag in 2 days - not even condensation.

Pipework & Rads. Unlike the boiler, these were all replaced just over a year ago - most of the pipework is the flexible plastic type except from the boiler and onto the rads. No visible leaks - even checked when cold to avoid evapouration.

Last night once the system had gone cold I shut the isolator valves and went to bed. This morning when I got up and opened them, the boiler pressure dropped indicating the pressure in the pipes and rads had fallen...

So, why can't I find any evidence of leaks? I would say I am having to add a pint of water (or thereabouts) every day. I still hear small amounts of air in the odd rad, but can't believe this is all going out of the auto valve?

Sorry it's a little long winded for a first post and I guess I know what the reply is going to be....

 

[taydo]

depends on the pipe work and how its routed but yes it is possible to carry on topping up for a week or more keep bleeding the rads. auto vent should always be open

 

[triva]

Hello All,
I've got similar problems with my potterton puma:

The low pressure light came on approx two weeks ago - and when I tried to increase the pressure via the filling loop the valve fell to bits inside and the pressure kept climbing!! after mild panic I turned the mains off, and got a replacement valve - fitted it, no prob.
Since then the pressure keeps dropping - if the heating is on all night It will have to be repressurised prob twice.
I've checked/Carried out:
No leaks thru overflow outside
radiators all bled
diaphram has air in rather than water
no leaks - the pipes are all in drylined walls rather than under the floor and the people below me have not complained of wet patches!!

One thing I have noticed is that the pressure drops a bit faster if the DHW is being used as well -is it possible that the heating water is leaking into the DHW in the boiler??

Also when you interpt the heating by turning on the hot taps, when you turn them back off, somtimes the boiler makes a boiling noise (like a bit of the water in the heating circuit bit has leaked out)???

Any help would be greatly appreciated!! I'm sick of glaring at it
Regards
triva

 

[goodtohelp]

Just keep auto open over time this will get rid of air. When you filled the sytem did you just fully opened loop and bled rads?

 

[triva]

Thanks for the response...

yes - when I refilled I just opened filling loop till the pressure went up to about 1 & 3/4 and bled the rads (till water started coming out).

Is the auto vent the thing at the top left side of the boiler stuck on the end of the pipe with a plastic grub screw in it??

Regards
triva

 

[goodtohelp]

Auto is usually located inside boiler near relief valve and usually has a car tyre like cap on it.

When filling system it is best to have all bleed screws closed. open filling loop a tiny bit starting on the ground floor bleed each one at a time until rad is half full then go do same up stairs, once that done go to first rad and fill it completely and repeat on each rad until all full. this could take upto 3 hours but will get rid of all air.