Hi,
has anyone any experience?

I bought these to solve a problem regarding noise and frequency of the
need to bleed a CH system.

They seem fairly ineffectual, blowing through the things prior to
fitting didnt seem to cofirm an airflow, but the noise from the system
and the amount of "air"? expelled seems to have increased.

If anything It would seem that they draw air in.

AB

On 14/05/2018 23:18, Archibald Tarquin Blenkinsopp wrote:
Hi,
has anyone any experience?

Yes, not impressed.

When first fitted to a drained down system they worked well and as shown
in the advertising Youtube videos.

I assume that these have a membain that expands when wet to seal the
valve. In my experience once sealed they never seem to open again.

When draining down the system subsequently these valves remain closed,
possibly because they take years to dry out in ambient temperatures, so
that on refilling a system a day or two later they don't work.

On an old system refilling a system may also disturb the sludge in the
radiator and this gets into that pin-hole in the valve. When I removed
one it wasn't clean!

If anything It would seem that they draw air in.

Or they are stuck closed and the air is just building up as you are
bleeding less often in the mistaken belief that the Alladin valves are
working.

I note that Allidin do replacement cartridges for their more expensive
look-alike professional devices which may indicate a fairly low life
expectancy.

--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

I guess the broader question is why you have to keep bleeding them in the first place.

On Tue, 15 May 2018 01:36:58 -0700 (PDT), wrote:

I guess the broader question is why you have to keep bleeding them in the first place.



Yes,
I always had a slight problem, I installed the basic unit
myself, but had a heating company fit a boiler/ stove.

The back boiler came out and so did the HW tank.

They also removed my 3 port valve, Honeywell and instead of taking the
feed to the radiators from the delivery side of the pump, the
radiators go to the suction. Frrom that point the air became
troublesome.

Recently the air in the system has increased despite using generous
amounts of inhibitor, I suspect a leak, but I didn't get around to
checking whether the gas is Hydrogen. When the pump kicks in, it
sounds like a mini waterfall for a few seconds. I have an auto vent
which I do not like to leave unattended in case the seal gets
contaminated.


I can isolate the rads, so I will build a pressure tester. I assume
theres nothing on the market for DIY use?

AB

Based on what you have said, given the timing, it does sound like there may well be a leak where they removed the valve and it is sucking in air.

What type of system do you have? Do you have a header tank for topping up the CH system or is it a pressurised system?

Assume you have fully bled the system and it continues to suck in air?

On Tue, 15 May 2018 02:50:33 -0700 (PDT), wrote:

Based on what you have said, given the timing, it does sound like there may well be a leak where they removed the valve and it is sucking in air.

What type of system do you have? Do you have a header tank for topping up the CH system or is it a pressurised system?

Assume you have fully bled the system and it continues to suck in air?

Hi
Thanks for the interest.

Yes the system has a header tank, I am not sure if I "fully" bled the
system, but it has been a couple of years since the upgrade and the
problem has actually worsened.

The system is in a bungalow, so each rad is dropped from the loft,
Ideally I should have used a level for setting a high spot, but space
was very restricted, the roof has a shallow angle.

I stuck a auto bleed valve at what seemed like the highest point.

I put isolation valves on the feed and return to the rads, so I think
I will drain the system, flush it and pessure test it with air.

I have put on a few stone since the initial installation, so listening
for leaks will take some intensive low calorie preparation :-(

The problem is compounded by the fact that I only use the house
intermittently, I cannot inspect tank levels since the introduction of
insulation and due to the acidic nature of the supplied water, I have
kept the mains water off when not present.

I have checked the pH of the incoming water and for the last year or
so the company seem to have got their act in order and the pH is at
7.0, so I would doubt that the water is reacting with the inhibitor.

On the assumption that there isn't a fundamental design issue with your system I would assume the more obvious reasons and rule them out first. When you are next there I would try the following

1. Check the header tank to ensure it has water in it and the ballcock hasn't stuck and is working correctly (likely to be the cause I am guessing )
2. If that is ok. With the hot water and heating off, bleed all the radiators. Check that the header is filling correctly to ensure it never goes below the top of the feed pipe during this process.
3. If this doesn't fix it and / or as an extra test, put something over the vent pipe (ie the one that dumps any expanded water into the header tank) so you can tell whether water is being pumped out of it or air sucked in. Could use a cloth for the former. For the latter you could seal a bit of balloon or similar over the end and you would see it getting sucked in or suspend a tub of water such that the end is submerged. If it is sucking water will be sucked out of the tub.

If none of this works post the results here and we could go to phase 2