Keston problem and solution



I have a problem with mine where it seems to get into a "hunting" state where it can't seem to decide on the right pump speed. It does this when it starts up and full output is not required. This causes all the heating pipes to twitch and bang. I have consulted Keston about it but they say it is a problem with the system not the boiler.
What is the issue you refer to above?

The guys who installed mine just used solvent cement.
--
Tim Mitchell

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Mine, which is 2.5 years old IIRC, has a detector in the condensate trap. It is after the U-trap part, so it will only detect condensate blockage external to the Keston. If the U-trap blocks with debris, or if the heat exchanger drain blocks as mine did, the condensate won't get as far as the detector in the trap, and won't trigger that fault detector.

Several people have reported vibrations like you would get from a 32' organ pipe. I suspect this is either combustion oscillating back up into the pre-burner area or maybe an undamped feedback loop in the venturi gas valve. I had this on initial installation as the preset mixture adjustment was preset incorrectly.

I solvent welded it. However, my flue spigot turned out to be faulty (Keston's weld between the stainless steel and the muPVC collar wasn't water tight). I broke it apart (at which point you could see why -- the glue they used hadn't gone all the way round), and remade it myself. I roughed up the stainless steel and used a ring of solvent weld around the lower 3/4 of the area, and used a special acid-resistant high temperature silicone sealant in the top 1/4 to preserve the water seal even if the solvent weld didn't seal to the stainless steel.
When that had all set, I then solvent welded it to the muPVC flue as before.
I also used a non-setting sealant on the exhaust spigot gasket. (Initially I had thought that's where the leak was. However, it turned out the leak was in the manufacture of the flue spigot.)
Having had a leak, after I had fixed and reassembled it, I left the garden hose running slowly into the flue terminal for perhaps half an hour to be double sure there were no more leaks in the condensate path. Leaks of condensate will rapidly wreck the boiler as someone else reported here a while back. If I ever fit another Keston, I will do this check with the garden hose as a matter of course as part of the commisioning procedure.
--
Andrew Gabriel

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Andrew Gabriel wrote:

I think its a combination of a very powerful fan and the small diameter of the air intake. Your analogy of the pipe organ might not be too far out. The powerful fan is needed to overcome the maximum resistance from the 50mm system. The 'fix' chokes off the air intake pipe to the fan.

They now ship a new and improved spigot which extends a little way inside the gasket. Presumably to prevent the condensate seeping through gasket.
The reason I asked about the jointing compound was to see if anyone else used a non-permanent seal, to aid future maintenance. I've used LSX which is also smeared on the gasket. Its a pity there isn't a more robust method of connecting the flue to the unit. IMO this is the weak link in the chain. A male flue pipe should go into a female port on the unit, which is how almost all other boilers are designed.
martyn
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On Fri, 24 Dec 2004 02:24:18 -0800, Martyn Pollard wrote:

I must download the latest manual.

Well by the book the boiler is not room sealed until you do. but I'll confess that I don't either but I do check the trap is full before I leave.

Ah 'buzz bombing' as I call it. AFAIK after consultation with their technical dept it is due to the burner being slightly weak. You really need a combustion analyser to make sure that the CO2 values are in spec at both the minimum and maximum rates.

This is not intended to be a demountable joint [1]. So I use bog standard Black Swan brand 'solvent weld'.
[1] I'm nigh on certain that all of the flue joints (and air duct also) are required to be permanent. Should the flue need to be taken from the boiler then the flue spigot unit should be unbolted form the boiler.
--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at www.diyfaq.org.uk
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Def seconded on that one (running weak). I set mine up using their timed meter rate method (wot a joke) and as a result set it far too weak. I hired an analyser (HSS do them) and once it was set up properly it hasn't been a problem. Running weak also caused serious ignition problems.
--
fred

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ground beef 1 cup finely chopped onions 7 - 12 cloves garlic 1 cup seasoned bread crumbs cup milk, 2 eggs Oregano basil salt pepper Italian seasoning, etc. Tomato gravy (see index) Fresh or at least freshly cooked spaghetti or other pasta
Mix the ground meats together in a large bowl, then mix each of the other ingredients. Make balls about the size of a baby?s fist (there should be one lying around for reference). Bake at 400for about 25 minutes - or you could fry them in olive oil. Place the meatballs in the tomato gravy, and simmer for several hours. Serve on spaghetti. Accompany with green salad, garlic bread and red wine.
Newborn Parmesan
This classic Sicilian cuisine can easily be turned into Eggplant Parmesan If you are planning a vegetarian meal. Or you could just as well use veal - after all, you have to be careful - Sicilians are touchy about their young family members...
6 newborn or veal cutlets Tomato gravy (see index) 4 cups mozzarella, 1cup parmesan, 1cup romano Seasoned bre
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30 - 45 minutes.
Umbilical Cordon Bleu
Nothing is so beautiful as the bond between mother and child, so why not consume it? Children or chicken breasts will work wonderfully also.
4 whole umbilical chords (or baby breasts, or chicken breasts) 4 thin slices of smoked ham, and Gruyere cheese Flour eggwash (milk and eggs) seasoned bread crumbs 1 onion minced salt pepper butter olive oil
Pound the breasts flat (parboil first if using umbilical cords so they won?t be tough). Place a slice of ham and cheese on each, along with some minced onion then fold in half, trimming neatly. Dredge in flour, eggwash, then seasoned breadcrumbs; allow to sit for a few minutes. Saut in butter and olive oil until golden brown, about 6 minutes on each side.
Shish Kababes
As old as the hills, this technique has employed seafood, beef, pork, lamb, poultry, and vegetables; just about anything can be grilled, and young humans are no exception!
High quality marinade (Teriyaki and garlic perhaps) 1 inch cubes of tender meat, preferably from the nursery Onions bell peppers Wooden or metal skewers
Marinate the meat overnight. Get the grill good and hot while placing meat, vegetables, and fruit such as pineapples or cherries on the skewers. Don?t be afraid to use a variety of meats. Grill to medium rare, serve with garlic cous-cous and sauted asparagus. Coffee and sherbet for desert then walnuts, cheese,
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