Never-ending problems with WB Greenstar 4000 15Kw system boiler

Iso

We are having problems with our brand new WB Greenstar 4000 15Kw system boiler on mains gas. It worked without any problem for 3 weeks then started malfunctioning. Error codes 2951 and 227. The engineer is adamant it is to do with the condensate pipe. He has "cleaned" the condensate pipe several times but the boiler malfunctions within 24 / 48 hours. The condensate pipework is inside so it is unlikely to have frozen (it hasn't been that cold around here). The engineer says the condensate pipe is clear but refuses (claims he "isn't allowed") to rod it through or use compressed air due to the "glue used on the joints". Any suggestions?

FreeBear

Error code 2951 is "Loss of flame too many times" and causes the boiler to shut down.

Error code 227 is "No flame detected after ignition". The manual then goes on to give a list of things to check.

Tip: Check the ceramic insulator is not damaged, this can cause the spark to earth, twist
and pull the ceramic insulator to ensure it is not broken.
▶ Check the gas supply to the property and the inlet on the gas valve.
▶ Check for low pressure when the gas valve opens.
▶ Gas valve failing to open: check for voltage to the valve and for possible blockage on
inlet filter of the gas valve.
▶ Obstruction in the air intake to the fan leading to incorrect CO2 ratio.
▶ Condensate siphon is blocked or restricted. Condensate pipe is frozen.
▶ Flue is blocked or restricted.
▶ Heat exchanger is blocked or restricted.
▶ Check the burner for damage.
▶ Check the spark electrode/lead for failure.
▶ Check the flame sense/lead for failure.
▶ Check the rectification ground (black wire to heat exchanger).

Checking the condensate pipe is easy enough - Just connect a flexible length of hose to the end and blow down it. All the other checks require the removal of the cover and the right test equipment. Any competent WB trained Gas Safe engineer should be able to run through the list pretty quickly. If this "engineer" of yours has failed to fix the fault, I'd give WB a call and get one of their guys out - A new boiler, so it should be fixed under warranty.

Eldi_Dos

When engineer cleaned the condensate pipe what was in it that needed cleaned.

Is the condensate pipe connected to the same pipework as kitchen sink, washing machine, dishwasher.

Just a thought if they are, could the flow from these passing the condensate pipe be enough to bring on the codes seen on the boiler.

Lorian

Call the Worcester help line, the will likely diagnose that over the phone. Could be a faulty gas valve.  If they think it is a boiler issue they should send an engineer assuming the warranty is registered.

Any grinding noise from it while it's failing to light?

I'm not an engineer but I have a few Worcesters

Iso

FreeBear said:

Error code 2951 is "Loss of flame too many times" and causes the boiler to shut down.

Error code 227 is "No flame detected after ignition". The manual then goes on to give a list of things to check.

Tip: Check the ceramic insulator is not damaged, this can cause the spark to earth, twist
and pull the ceramic insulator to ensure it is not broken.
▶ Check the gas supply to the property and the inlet on the gas valve.
▶ Check for low pressure when the gas valve opens.
▶ Gas valve failing to open: check for voltage to the valve and for possible blockage on
inlet filter of the gas valve.
▶ Obstruction in the air intake to the fan leading to incorrect CO2 ratio.
▶ Condensate siphon is blocked or restricted. Condensate pipe is frozen.
▶ Flue is blocked or restricted.
▶ Heat exchanger is blocked or restricted.
▶ Check the burner for damage.
▶ Check the spark electrode/lead for failure.
▶ Check the flame sense/lead for failure.
▶ Check the rectification ground (black wire to heat exchanger).

Checking the condensate pipe is easy enough - Just connect a flexible length of hose to the end and blow down it. All the other checks require the removal of the cover and the right test equipment. Any competent WB trained Gas Safe engineer should be able to run through the list pretty quickly. If this "engineer" of yours has failed to fix the fault, I'd give WB a call and get one of their guys out - A new boiler, so it should be fixed under warranty.

The engineer has put his mouth to the pipe and blown through it - apparently this proves there is no blockage. What I can't get my head around is that the boiler worked for 3 weeks and suddenly this issue arose. There is a lot of gurgling when the boiler is trying to light so they are adamant this is an issue with the condensate pipe. They say the condensate pipe links to the toilet  (but we cannot be 100% sure as it is all under floor and they are reluctant to look under the floor). They say the condensate pipe probably runs uphill under the floor: if that is the case how come the previous boiler worked fine and how come the new boiler worked fine for three weeks? I am just trying to get my head around why is it "definitely" the condensate pipe when it seems it could be a whole raft of other issues (as you have listed above) but all those issues have been dismissed out of hand, without inspection. We have had WB out and they took one look at the condensate pipe, which had four 90 degree bends that we could see and said "it's the condensate pipe". The four 90 degree angles have now been replaced with two 45 degree bends but the boiler gurgled a bit before lighting this morning.

Iso

Eldi_Dos said:

When engineer cleaned the condensate pipe what was in it that needed cleaned.

Is the condensate pipe connected to the same pipework as kitchen sink, washing machine, dishwasher.

Just a thought if they are, could the flow from these passing the condensate pipe be enough to bring on the codes seen on the boiler.

The only "cleaning" they have done is to blow through it with their mouth. They have not done anything else. They did it when they installed the new boiler and several times since but they refuse to rod it or use compressed air. We think the condensate pipe is attached to the toilet (the boiler cupboard is next door to the toiler, both on the first floor). We have tried drain clear in all sinks etc but that has not made any difference. The dishwasher and washing machine use the same drains as the kitchen sink. 

Iso

Lorian said:

Call the Worcester help line, the will likely diagnose that over the phone. Could be a faulty gas valve.  If they think it is a boiler issue they should send an engineer assuming the warranty is registered.

Any grinding noise from it while it's failing to light?

I'm not an engineer but I have a few Worcesters

We called WB who thought it was unlikely it was the condensate pipe as the boiler had worked for three weeks before starting to play up. They sent an engineer - the paperwork left says 

“the product is not installed in accordance with manufacturers installation instructions”

-              “An external factor was the root cause of us attending to your product”

-              “Incorrect installation”

-              “Condense pipework installed sharp bends and blocked”

-              “Replace, clear condense run”.

We reported this to our installers who were upset that we had spoken to / called out WB. Our installers say they have spoken to a WB director and that the director refutes the 90 degree bends is an issue: all very defensive. 

The WB engineer and our installers all say the gas supply is fine.

A new flue was installed at the same time as the boiler. Apparently that is fine.

We have really lost confidence with all involved as it just doesn't make sense that it is the condensate which worked for three weeks then started playing up. The boiler makes a gurgling sound when it is failing to light. Is there anything OTHER than the condensate pipe that could be causing this?

JohnB47

This is all very strange. So a WB director is saying that their engineers conclusion is wrong? Perhaps you could get the name of that director from your installer and speak to them yourself and as ask, what do I do now if you, the manufacturer, can't agree what's wrong? Get another WB engineer out?

It might help to know that the condensate water on the Greenstar range (and some others) is first stored in a little internal tank and when this tank has filled to a certain level, siphonic action drains it down the condensate pipe. There is no pump as such I believe. It takes a while for the condensate to build up to the point of siphon, so that might explain the three week delay to the problem showing.

I know you shouldn't have to do this (the engineer should have) but if it was me, I would look under the boiler and find the white plastic pipe running vertically down at the back. I would look at the top and find how it was fitted to the boiler - probably some sort of compression joint - and undo it. I would then move the pipe to the side and put a container under the fitting to catch any drips or flow and turn the boiler on. If it fires up as normal, then the condensate pipe is indeed the problem. If it doesn't, it can't be the pipe, so I'd report that to WB.

As I say - the engineers should have checked the level and action of the siphon tank and tried running the boiler with the pipe disconnected. Basic fault finding technique really Did he do any of this, do you think?

Edit: I notice that one of the fault code reasons quoted earlier was "Condensate siphon is blocked or restricted." This doesn't mean that it is only the condensate pipe that could be the problem. It could be the condensate tank siphon mechanism that's faulty, hence my advice.

FreeBear

JohnB47 said: It might help to know that the condensate water on the Greenstar range (and some others) is first stored in a little internal tank and when this tank has filled to a certain level, siphonic action drains it down the condensate pipe. There is no pump as such I believe. It takes a while for the condensate to build up to the point of siphon, so that might explain the three week delay to the problem showing.

I know you shouldn't have to do this (the engineer should have) but if it was me, I would look under the boiler and find the white plastic pipe running vertically down at the back. I would look at the top and find how it was fitted to the boiler - probably some sort of compression joint - and undo it. I would then move the pipe to the side and put a container under the fitting to catch any drips or flow and turn the boiler on. If it fires up as normal, then the condensate pipe is indeed the problem. If it doesn't, it can't be the pipe, so I'd report that to WB.

The condensate trap should be primed at installation time by pouring ~200ml of water down the exhaust flue connection (before attaching the flue).

The white plastic pipe is usually a push fit over (or in to) a rubber spigot, so easy to disconnect. With my boiler (a Viessmann), it is a flexible length of pipe about 300mm long.

Iso

JohnB47 said:

1. This is all very strange. So a WB director is saying that their engineers conclusion is wrong? Perhaps you could get the name of that director from your installer and speak to them yourself and as ask, what do I do now if you, the manufacturer, can't agree what's wrong? Get another WB engineer out?

2. It might help to know that the condensate water on the Greenstar range (and some others) is first stored in a little internal tank and when this tank has filled to a certain level, siphonic action drains it down the condensate pipe. There is no pump as such I believe. It takes a while for the condensate to build up to the point of siphon, so that might explain the three week delay to the problem showing.

3. I know you shouldn't have to do this (the engineer should have) but if it was me, I would look under the boiler and find the white plastic pipe running vertically down at the back. I would look at the top and find how it was fitted to the boiler - probably some sort of compression joint - and undo it. I would then move the pipe to the side and put a container under the fitting to catch any drips or flow and turn the boiler on. If it fires up as normal, then the condensate pipe is indeed the problem. If it doesn't, it can't be the pipe, so I'd report that to WB.

4. As I say - the engineers should have checked the level and action of the siphon tank and tried running the boiler with the pipe disconnected. Basic fault finding technique really Did he do any of this, do you think?

5. Edit: I notice that one of the fault code reasons quoted earlier was "Condensate siphon is blocked or restricted." This doesn't mean that it is only the condensate pipe that could be the problem. It could be the condensate tank siphon mechanism that's faulty, hence my advice.

I have added numbers to your paragraphs so you can easily see my replies.

1. Apparently yes. Our installers say they called WB, spoke to a director, and the director said the 90 degree angles (four of them) would not be an issue. The WB engineer was horrified to see the 4x 90 degree angles. Very sensible suggestion, we will ask the installer for the name of the director they spoke to and try to get in touch with the director ourselves. 

2. Here is a photo of the condensate tank taken on Monday. We thought it showed the water was about half way up the down pipe on the right but, on closer inspection, that is a little ridge in the pipe. It seems the tank was, in fact, about five-sixths full. I wonder if the blockage is in the syphon mechanism?
 

3.  I am not sure we are up to doing that! But we will certainly ask the installer if they have done what you suggest and go back to WB if it doesn't fire up.   

4. I don't know but we will ask

5. Yes, I am beginning to wonder if it is the siphon mechanism.

Albermarle

The white plastic pipe is usually a push fit over (or in to) a rubber spigot, so easy to disconnect. With my boiler (a Viessmann), it is a flexible length of pipe about 300mm long.

I have a WB greenstar ( not the same model as the OP)

A short length of rigid plastic tube comes out from the bottom of the boiler at an angle. As you say this is connected to the white plastic outlet pipe by a rubber spigot. It is easy just to pull the white outlet pipe out of this spigot as I have done it before.