....I've got my combi-boiler (Halstead ACE) protected scale wise by a Liff Combi-Flo (just the boiler).....every couple of months the plate heat exchanger seems to get clogged up (it's not very big on an ACE) by bits of debris....having removed a rad recently it didn't appear to be the water in the CH system that was full of the debris so my attentions turned to the Combi-Flo. Having looked at the device there is a filter on the connection from the mains but no filter on the connection to the boiler......is it possible that the Siliphos crystals are breaking up and clogging up the heat exchanger ? Anyone had similar problems ? Would a Combimate be a better option ?
Problem with Liff Combi-Flo ?
- Thread starter wanleg
- Start date
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have they been changed in the last 12 months ?
yes about mid December time.....I think the recommendation is every 12 months for a single appliance but I prefer to swap every 6 to be sure.
wanleg said:
I have had the exact same repetitive problem using a combination of a Halstead Ace High combi boiler and Liff Combi-Flo.
The Halstead engineer was out twice in the first two years under the warranty and this week BGas have been out under my new maintenance contract with them. The boiler is only two and a half years old and is becoming a pain in the hole.
If anybody can give a solution to this problem I will be eternally grateful.
Ta.
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I have mine on cover with BG also. You will find that BG will come out a few times then make noises that the problem isn't with the boiler and therefore they are not obliged to fix...I've been living with this now for over two years....for sure it's not the Liff Combi-Flo causing the problem as the side of the heat exchanger that has the mains cold is completely clear.....the only side that requires cleaning is the side from the primary heat exchanger. I've just (yesterday) put one of these www.magnaclean.co.uk on order having recently already tried an inline Y strainer (on the 22mm heating return) and cleaning and dosing with Fernox Concentrate Restorer and protector. I'll let you know how I get on.....until then keep cleaning every six weeks or so like I do.
The Siliphos is quite effective at reducing the effects of scale.
Apparently vaillant do not recommend them on their boilers because a "white jelly" like deposit can form on the cold water side of the plate HE.
The original poster did not say which side of the plate HE the blockage formed. I expect that it was on the primary ( heating ) side which is nothing to do with the combi-mate and caused because the rads were not power flushed when the boiler was installed.
An inline strainer should help to reduce this although the more expensive magnetic filter will be more effective. Really both components are required although its not too difficult to take out the HE and clean it as a DIY project.
Neither of these are adressing the real problem of dirt in the system. Power flushing is the real solution!
Tony Glazier
Apparently vaillant do not recommend them on their boilers because a "white jelly" like deposit can form on the cold water side of the plate HE.
The original poster did not say which side of the plate HE the blockage formed. I expect that it was on the primary ( heating ) side which is nothing to do with the combi-mate and caused because the rads were not power flushed when the boiler was installed.
An inline strainer should help to reduce this although the more expensive magnetic filter will be more effective. Really both components are required although its not too difficult to take out the HE and clean it as a DIY project.
Neither of these are adressing the real problem of dirt in the system. Power flushing is the real solution!
Tony Glazier
I'd agree (and disagree!) with Tony.
Yes - it seems very likely that the problem is on the PRIMARY side of the heat exchange and therefore NOTHING to do with the Siliphos gadget and / or the mains water.
(Black) Magnetite deposits in the Primary side of the Secondary (Hot Water) heat exchanger are very common and a serious problem. A magnaclean-type device WILL remove virtually all the magnetite out of the system mostly before it ever gets to the boiler.
A (simpler and cheaper) particle filter will remove particles over a certain size but is smaller and needs to be cleaned out more often.
BUT
Corrosion inhibitor is also needed to prevent magnetite being formed (inside the radiators) in the first place.
Magnetite DOES 'crystallise out' inside the boiler EVEN WHEN there is a particle filter. Problem is that magnetite is SLIGHTLY soluble in water, so it will tend to dissolve from the stuff held in the filter and then immediately redeposit inside the boiler.
The trouble with power flushing is that it takes a VERY long time to do properly and needs the right chemicals and a POWERFUL machine to get enough flow through each rad in turn to shift the corrosion deposits. If the CUSTOMER is prepared to pay the high cost - then no problem. It's entirely up to them. But there is NO SUCH THING as an effective and CHEAP flush.
Yes - it seems very likely that the problem is on the PRIMARY side of the heat exchange and therefore NOTHING to do with the Siliphos gadget and / or the mains water.
(Black) Magnetite deposits in the Primary side of the Secondary (Hot Water) heat exchanger are very common and a serious problem. A magnaclean-type device WILL remove virtually all the magnetite out of the system mostly before it ever gets to the boiler.
A (simpler and cheaper) particle filter will remove particles over a certain size but is smaller and needs to be cleaned out more often.
BUT
Corrosion inhibitor is also needed to prevent magnetite being formed (inside the radiators) in the first place.
Magnetite DOES 'crystallise out' inside the boiler EVEN WHEN there is a particle filter. Problem is that magnetite is SLIGHTLY soluble in water, so it will tend to dissolve from the stuff held in the filter and then immediately redeposit inside the boiler.
The trouble with power flushing is that it takes a VERY long time to do properly and needs the right chemicals and a POWERFUL machine to get enough flow through each rad in turn to shift the corrosion deposits. If the CUSTOMER is prepared to pay the high cost - then no problem. It's entirely up to them. But there is NO SUCH THING as an effective and CHEAP flush.
Having looked into this at the weekend I have been told by several people that it is actually a fault specific (if not unique) to the Halstead boiler that I have. Something to do with the way the heat exchanger is positioned inside the boiler and the size of the holes which are easily clogged.
The advice that I got was to maybe persevere with the boiler for another year or two but in the long term the only solution was to replace it as it was inherently faulty by design and also that the circuits on them fail with alarming regularity and repetition.
But I might try all of these other possible solutions you have mentioned in the meantime.
The advice that I got was to maybe persevere with the boiler for another year or two but in the long term the only solution was to replace it as it was inherently faulty by design and also that the circuits on them fail with alarming regularity and repetition.
But I might try all of these other possible solutions you have mentioned in the meantime.
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