Leaking Grant Boiler

Alfster

Hi guys,

Anyone any idea what could be leaking as per photos? There aren’t many local oil boiler specialists and they are all fully booked. Just want to know if I should switch it off and not use it? It’s definitely not oil as I have smelt it.

It’s leaking on the left side (opposite side to condenser). 

The above photos were from the other day but today it has leaked more:

Annoyingly it was only serviced in April and it is only two years old. 

matt_drummer

Who installed that?

It seems to be sitting on a wooden pallet.

Is that normal?

What is with the plastic piping?

Have you checked the joints?

Maybe the base isn't stable enough/

Could it be moving or be able to be moved accidently/

It looks like rusty water.

Is it a pressurised or vented system/

If it is pressurised I would assume your water pressure is falling?

FreeBear

Alfster said: Annoyingly it was only serviced in April and it is only two years old. 

Still under warranty ?

Give Grant a call and get one of their engineers out to inspect & repair.

Alfster

matt_drummer said:

Who installed that?

It seems to be sitting on a wooden pallet.

Is that normal?

What is with the plastic piping?

Have you checked the joints?

Maybe the base isn't stable enough/

Could it be moving or be able to be moved accidently/

It looks like rusty water.

Is it a pressurised or vented system/

If it is pressurised I would assume your water pressure is falling?

Previous owners had it installed when selling house which we bought 2 years ago. No! Everyone who has serviced or done something to it has commented about the wooden pallet. When I contacted the people that installed it they said ‘Grant told us to put it on the pallet it came in” 🤔 

The plastic piping I believe to be for the condenser as it’s a condensing oil boiler. 

No I think it is stable currently and I don’t think it could have been knocked. It’s in the cellar and we rarely go down there. 

What joints would you check? 

Yes I would describe it as rusty water. 

It’s a vented system so cold water fed from the loft. The pressure gauge for the hot water cylinder appears to be where it normally is (1.2-1.5bar when the boiler is off and 2.0 bar when it’s on). 

Do you think the crate situation is bad enough that I should get an engineer to take it off and put it into a new base. What I wanted is for it to go where the old oil boiler appears to have been which is a main chimney. Engineers that have been round think the previous owners do it on the cheap because the new boiler is condensing so they said if they left it on the original concrete plinth it would have required lining the chimney to avoid moisture damage compared to to the old non condensing boiler which would have burned much hotter. It’s really annoying as not only do you get a plastic tacky flue outside the front door but the boiler is kind of in the middle of the room rather than tucked into a fire place. 

Thanks for the advice. 

matt_drummer

I would turn the electric supply of and have a good look and feel around.

It is a fair amount of water and it should be easy to find.

Start at the top and work down until you find moisture, that is where it is coming from.

I don't see why you have a pressure guage on a vented system?

If you are not losing pressure then there is no leak.

Could this just be condensation not being disbursed where it is intended to be?

I have to say, I don't like the pallet, hardly secure with oil, water and electricity.

I would not have done that and would never accept that as in installation had I commissioned it.

lohr500

I would also start by checking the condenser drain situation.

I think that external white unit in your third photo will be the condensate pump which should pump the condensed water back up to ground level and away. It will contain a pump motor actuated by a float or sensor which should cut in as the level of condensate in the pump unit rises. If you are comfortable with electrics and basic plumbing you should check that unit first. Locate the power supply though first and make sure it is isolated before messing with the unit. Hard to say for sure, but that pump unit looks to be older than two years, so it may have been in use on the old boiler that was replaced.

The only thing that makes me think it may not be the condensate drain is the fact that the water is dirty. That could point to a leak from the boiler circuit. Either from a loose pipe fitting or worst case from the boiler internals.

If it has been installed and serviced by Grant approved engineers in the past then it should be covered by Grant's warranty at two years old.

As suggested in the previous posts, start with an inspection of that condenser drain arrangement and then look around the internals to see if you can see where the water is coming from.

Hopefully it is a simple thing like that condenser pump not working or a loose pipe fitting inside the housing.

Alfster

Thanks to all for your help. I did check the condensate pump and couldn't see anything. However, the engineer who was booked up until the end of next week had a cancellation today so he came round (I am out at work). My wife said there is a fault with the external flue so it's rain water coming in and mixing with the intake. 

matt_drummer - yes I'm not sure why it is pressurised when it is vented (cold water fed). Here is a picture inside the airing cupboard:



The pressure gaugue sometimes falls a bit over time so needs topping up with the filling loop otherwise the rads on the end of the line are barely even warm. Needs to be at 2 bar when the central heating is on to heat every rad. Does anybody know if there is a limit of rads for this Grant boiler? We have 15 rads plus wet UFH in the kitchen and utility. I sometimes feel it struggles. I think it is because most of those rads are large too. I have played around with trying to balance them by closing off the ones at the start of the line and fully open ones at the end but is always needs 2 bar no matter how much I fiddle. Online it says 1.5 bar should be enough. 

I told my wife to mention about moving it off the crate and he said the plumbing company they work with will look into it but it depends on the condition of the chimney flue. He said the plumbing company is also the people to contact today to arrange sorting the faulty flue. If the old boiler was using the chimney the current one is right next to surely that would work even if it means it needs a liner? The concrete plinth is already there underneath it. 

Could anyone kindly give an opinion on what I should do about the crate situation? Like I suggested, would you get someone to move it to the old spot with a chimney liner?

What I'm sure will amaze you all is that Oftec inspected the boiler install a year or so after we moved in and approved it! No menioned in the report of the wooden crate being unsuitable. 

matt_drummer

I think you have a pressurised non vented system.

I assume you have no feed and expansion tanks in the loft?

FreeBear

Alfster said:  We have 15 rads plus wet UFH in the kitchen and utility. I sometimes feel it struggles. I think it is because most of those rads are large too. I have played around with trying to balance them by closing off the ones at the start of the line and fully open ones at the end but is always needs 2 bar no matter how much I fiddle. Online it says 1.5 bar should be enough.

Get yourself a couple of thermometer modules along with a couple of pipe clips. Assemble as shown in the piccie below. Turn up all the TRVs to max, and close off all the lockshields. With the boiler running at normal temperature, start with the radiator closest and open up the lockshield a tad. Using the thermometers, you want to aim for a ~10°C difference. Repeat for all the radiators in turn, and don't forget the UFH. You may have to go back and tweak some of the radiators once things settle down.

Having radiators that are "too large" is actually advantageous with a modern condensing boiler - It means you can turn the flow temperature down for a higher boiler efficiency without getting cold.

FreeBear

[Deleted User] said:

FreeBear said:

Get yourself a couple of thermometer modules along with a couple of pipe clips. Assemble as shown in the piccie below. Turn up all the TRVs to max, and close off all the lockshields. With the boiler running at normal temperature, start with the radiator closest and open up the lockshield a tad. Using the thermometers, you want to aim for a ~10°C difference. Repeat for all the radiators in turn, and don't forget the UFH.

I like the pipe clip sensor holder 

That sensor looks like a 'waterproof' DS18B20; these caused me no end of grief when I tried building my own differential temperature gauge (the main issue being, that they were very slow to react, when used in a 'contact' application). My trials and tribulations are to be found HERE if anyone is interested.

I entered up buying a commercial meter that uses Type K thermocouples instead. (Like this one)
I also bought a pair of Pipe Clamps containing said thermocouples. (Like these).

In the end, I came to the conclusion that the classic procedure for balancing radiators, really DOESN'T WORK!

The problem I encountered on my previous (non-modulating) Gas boiler and my current (non-modulating) Oil boiler, is the difficulty in getting the system into a stable state (i.e. the boiler is forever 'short-cycling'). Other components in the system don't seem to help either - eg the pump changing its flow rate, and the Bypass short-circuiting the flow.

The sensor on those LCD modules are a little smaller than a DS18B20, so I assume it is a PTC/NTC sensor - They certainly react quicker to temperature changes than the DS18B20s I've used. The other problem with the LCD modules is calibration - None of the modules I have give the same readings, and there is no way to adjust the offset. So one ends up having to add/subtract mentally.

And yes, I do agree that trying to balance radiators when the pump or boiler is moving the goal posts is problematic (apologies for teaching you how to suck eggs, but the brief how-to may benefit others). I have a fan assisted wet heater, and switching between Hi & Lo settings makes a big difference to the temperature drop - Best I can do is adjust the flow to "meh, near enough" and leave it at that. With a new boiler fitted earlier this year (modulating output, smart pump), I'm waiting for a cold spell so that the system can be tuned & balanced. With so many variables, I know I won't get it perfect, so will try to balance comfort against fuel efficiency.