Issue with Boxt boiler install - Need advice

D-Ranged

D-Ranged

D-Ranged

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Hi all,

Just got our knackered old conventional boiler system replaced with a new Worcester combi.

Install happened over two days and seemed to go ok. He tested it and showed me it working then after a while it had dropped pressure. He refilled it and said it happens sometimes. Then finished off the last bits like the drain outside etc.

Signed everything off, misses had a shower. I went to have one after and no hot water. Boiler had dropped to 0 pressure. Refilled it again, had a shower and checked it again. Pressure has dropped slightly but left it.

Checked a few hours later. It's back at 0. Spoke to the engineer who came the next day with some leak sealant. Ran that through the system for 30 mins with the heating on and left. Within a few hours, it was back at 0 again.

His last message was telling me to isolate the heating so it doesn't leak. I asked him which parts to do but he hadn't replied for two days and not answering the phone.

I know the added pressure can show leaks, so before I go in all guns blazing, does anyone have any advise on what I should do or am I **** out of luck, and have to rip the floor up and see if I can find the leak?
 
It looks like it's a fault with the installation, so hope that you can contact the installer shortly and they should be sorting it out.

It might be worth refilling it to get the system back to pressure, and then watching the pressure to see how quickly it drops to zero (without using any hot water), as this might help with your diagnosis. Then try the same thing and using hot water, and see what happens to the pressure.

I think 0 pressure can be caused by a number of things, but really they should be sorting it out.
 
radderfire said:
It looks like it's a fault with the installation, so hope that you can contact the installer shortly and they should be sorting it out.

It might be worth refilling it to get the system back to pressure, and then watching the pressure to see how quickly it drops to zero (without using any hot water), as this might help with your diagnosis. Then try the same thing and using hot water, and see what happens to the pressure.

I think 0 pressure can be caused by a number of things, but really they should be sorting it out.
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I have been on to them this morning and they're sending a different engineer out tomorrow afternoon.

I have refilled it multiple times. It does drop pretty quickly.

The weird thing is, sometimes it will last a while other times or will drop within an hour or so. Sometimes it will get down to 0.4 and then slowly drop down other times it will drop down to 0 very fast.

I work from home and I don't really use hot water much at all, I usually have cold showers, so that's the more confusing thing.
 
If it wasn’t leaking before and now it’s leaking following a boiler change. The obvious culprit is the pressure relief valve in the boiler.

You’d know if the heating system was leaking that much water elsewhere because you’d have water everywhere.
 
b0rn2sk8 said:
If it wasn’t leaking before and now it’s leaking following a boiler change. The obvious culprit is the pressure relief valve in the boiler.

You’d know if the heating system was leaking that much water elsewhere because you’d have water everywhere.
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There were no leaks from before, that I know of. Never heard the tank in the loft constantly filling up.

Other than the one tap in the upstairs bedroom (bungalow with loft conversion) all our pipes are under the floor, but yes, you're right, if it was leaking that bad I'd be able to hear it coming out somewhere, which I certainly can't.

I have checked all the pipes up there and they are ok.

It does seem to fill it's pressure very quickly to 1bar, it's almost instant after pulling the lever, which seems a little weird to me, then takes a about 3-5 seconds to get to 1.2bar after that
 
The expansion vessel (presumable in the boiler) could well be broken which is casing the water to be dumped by the pressure relief valve.

It’s really not that uncommon of a fault and anyone competent should be able to identify the issue in minutes.
 
b0rn2sk8 said:
The expansion vessel (presumable in the boiler) could well be broken which is casing the water to be dumped by the pressure relief valve.

It’s really not that uncommon of a fault and anyone competent should be able to identify the issue in minutes.
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Fingers crossed this guy coming tomorrow can work it out!
 
b0rn2sk8 said:
The expansion vessel (presumable in the boiler) could well be broken which is casing the water to be dumped by the pressure relief valve.

It’s really not that uncommon of a fault and anyone competent should be able to identify the issue in minutes.
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This, 100%. Or the vessel has no pre charge from the factory.
 
Had the other engineer round earlier.

He said the workmanship looks fine, but noticed there is no shock arrestor which is apparently a requirement for the Worcester boilers. So that is most likely causing the issue with the cold taps turning the boiler on.

He doesn't think there is a leak in the system and potentially a fault with the boiler itself.

I am waiting to hear back from boxt on what they're going to do about it now.

Funnily enough, I had a message from the previous engineer not long after the new one arrived, so Boxt must have said something to him!
 
Could be a leak on a heating pipe somewhere. Open vented system water pressure is 0.1 bar. Switching to a combi is ten times that. Also putting Sentinel leak sealer in a combi boiler system is really not a good idea.
 
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henry hoov3r said:
Could be a leak on a heating pipe somewhere. Open vented system water pressure is 0.1 bar. Switching to a combi is ten times that. Also putting Sentinel leak sealer in a combi boiler system is really not a good idea.
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Yeah I did ask and the engineer didn't seem to think so, but it's a possibility.
 
D-Ranged said:
Yeah I did ask and the engineer didn't seem to think so, but it's a possibility.
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Quick and easy way to rule it out would be to turn off the heating isolation valves underneath the boiler. You just need a flat screwdriver. The hot water will still work perfectly fine and if it doesn’t lose pressure you know it’s system related.
 
henry hoov3r said:
Quick and easy way to rule it out would be to turn off the heating isolation valves underneath the boiler. You just need a flat screwdriver. The hot water will still work perfectly fine and if it doesn’t lose pressure you know it’s system related.
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I did this, this morning and so far it hasn't dropped pressure, so looks like it is probably a leak in the heating system somewhere. At least it gives me a little time to pull the floor up and have a look before I'd need the heating.

I feel like the guy that came yesterday was just trying to get some work. Boxt called me this morning and said it doesn't need a shock arrestor for the cold water issue and to just adjust some settings on the boiler, which I did and it has stopped that issue.

IAmATeaf said:
I’d also check to see if adding a leak sealer affects your boiler warranty?
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From what I can see, it doesn't. I have told Boxt, so they have it noted in their system. So I would hope it would be on them, should anything like that come up.

The engineer only put one bottle in which I don't think is enough at all from looking at the instructions in the vack. And the amount of times a day it was dropping pressure, I imagine most of it is under the floor somewhere now.
 
Did the new engineer confirmed if the over pressure valve is faulty? That would let the water out via a pipe rather than leaking it into the house at a joint.
 
How long does it take to lose pressure? If it’s dropping one bar overnight then it’s more than likely on the downstairs circuit. You would think losing that much water if it was on the upstairs circuit it would likely show up on the ceiling somewhere. So if you was going to lift the floor up boards up i would start there.
 
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