The 2007 Flair 8000 that we went to see at Bristol had only had one documented fluid change and that was by Travelworld in 2012. When we viewed the van, the salesman had already got the circulation pump running, although the heating was not on. We thought this was a bit odd. His explanation was that the pump sometimes didn’t want to start and that he knew it needed replacing. He had had the van in stock for over a year tho’ so surely he could have managed to replace the pump in that time.
Anyway, we got to thinking that it would be useful to know how to establish whether corrosion was present in an Alde system. I contacted Alde and they were very helpful so I thought I’d post their information here for others to read.
The only reliable test is to take a sample from the return on the boiler. This is best done by a technician.
They can clamp off the circulation pump and flow assembly, for example. Then, placing down old towels to collect leakage, unclip and remove the circulation pump mounted on the side of the boiler. The duct itself can be quickly capped by a 1900-030 blank. Much of this process is shown in the video below.
You can drain the pump into a glass. Then look inside the pump's port; it should be free of any sludge.
The fluid in the glass can be tested with a pH strip. It should be pH 7-8, no lower. Holding it up to the light, it should be clear of debris and a strong colour, not straw coloured, brown or black. It should neither smell of fish or vinegar. If you can't get a sample from the return on the boiler, these tests still apply to fluid in the expansion tank.
In theory both fluids should be the same. But if old, bad fluid has been topped up with new, good fluid, it might not have mixed yet.
I then asked roughly how long it would take for any newly added fluid to become well mixed with old bad fluid. Reply as follows:
It depends on the pump speed, but two cycles should do it, so about 20 minutes on full power gas and electric, desired temp set to 30 deg C on the Alde control panel.
It still won't give you an idea of the condition of the surfaces in the boiler, you'd need the sample from the return for that. But it will give you a good indication of the condition of the fluid.
This video's a pretty good, all-round guide on the subject:
So while I can’t see many dealers or private sellers being too keen on a prospective buyer taking the circulation pump apart, running the heating for 20 mins and taking a sample from the expansion tank should not be a problem - unless they have something to hide. At least it’s a good starting point if you are faced with a van with an incomplete or non-existent fluid change history.
Anyway, we got to thinking that it would be useful to know how to establish whether corrosion was present in an Alde system. I contacted Alde and they were very helpful so I thought I’d post their information here for others to read.
The only reliable test is to take a sample from the return on the boiler. This is best done by a technician.
They can clamp off the circulation pump and flow assembly, for example. Then, placing down old towels to collect leakage, unclip and remove the circulation pump mounted on the side of the boiler. The duct itself can be quickly capped by a 1900-030 blank. Much of this process is shown in the video below.
You can drain the pump into a glass. Then look inside the pump's port; it should be free of any sludge.
The fluid in the glass can be tested with a pH strip. It should be pH 7-8, no lower. Holding it up to the light, it should be clear of debris and a strong colour, not straw coloured, brown or black. It should neither smell of fish or vinegar. If you can't get a sample from the return on the boiler, these tests still apply to fluid in the expansion tank.
In theory both fluids should be the same. But if old, bad fluid has been topped up with new, good fluid, it might not have mixed yet.
I then asked roughly how long it would take for any newly added fluid to become well mixed with old bad fluid. Reply as follows:
It depends on the pump speed, but two cycles should do it, so about 20 minutes on full power gas and electric, desired temp set to 30 deg C on the Alde control panel.
It still won't give you an idea of the condition of the surfaces in the boiler, you'd need the sample from the return for that. But it will give you a good indication of the condition of the fluid.
This video's a pretty good, all-round guide on the subject:
So while I can’t see many dealers or private sellers being too keen on a prospective buyer taking the circulation pump apart, running the heating for 20 mins and taking a sample from the expansion tank should not be a problem - unless they have something to hide. At least it’s a good starting point if you are faced with a van with an incomplete or non-existent fluid change history.