Y
YorkshireJumbo
We have a pressurised heating system with 3 circuits. The system is almost 13 years old, but has been regularly maintained. We recently had a new bathroom fitted with towel radiators, and had the whole system flushed as our original builder used porous plastic pipe where he could. At the same time, we had one of our pressure vessels replaced as it had failed. Since then, our hot water seems to be getting worse, and recently it seems to disappear very quickly. Today the hot water was "on" for several hours, then my daughter started running a bath. She stopped it to put in some lotion or other, but the water went cold soon after she turned it back on.
I've had a look at the tank and can't see anything running from the overflow. The pressure in the system seems fairly constant, so I don't think there are any leaks. There are five copper pipes into the top of the tank (sorry if this is blindingly obvious) - cold water feed, hot water take-off, overflow and 2 pipes for the heating circuit (see here). When the hot water is "on", one of the circuit pipes (smaller diameter pipes in pic) is hot to the touch, one almost stone cold. I'm assuming the coil isn't that efficient at heat transfer, so I was wondering if there was an airlock in the system. Could it be anything else?
I notice that both pipes have a T with an 8-inch upright capped with a knurled fitting which also has a slot in the top. I thought these might be bleed valves as they are the highest part of the circuit, but I was unable to turn them with a large screwdriver or wrench - I didn't try too hard in case I was wrong and I broke something.
Any help gratefully received. I'm happy to call someone out if needed, but I want to cover the obvious first. I'm OK with DIY and have done a couple of bit of maintenance with compression joints but haven't done any soldering since a brief demo 25 years ago!
I've had a look at the tank and can't see anything running from the overflow. The pressure in the system seems fairly constant, so I don't think there are any leaks. There are five copper pipes into the top of the tank (sorry if this is blindingly obvious) - cold water feed, hot water take-off, overflow and 2 pipes for the heating circuit (see here). When the hot water is "on", one of the circuit pipes (smaller diameter pipes in pic) is hot to the touch, one almost stone cold. I'm assuming the coil isn't that efficient at heat transfer, so I was wondering if there was an airlock in the system. Could it be anything else?
I notice that both pipes have a T with an 8-inch upright capped with a knurled fitting which also has a slot in the top. I thought these might be bleed valves as they are the highest part of the circuit, but I was unable to turn them with a large screwdriver or wrench - I didn't try too hard in case I was wrong and I broke something.
Any help gratefully received. I'm happy to call someone out if needed, but I want to cover the obvious first. I'm OK with DIY and have done a couple of bit of maintenance with compression joints but haven't done any soldering since a brief demo 25 years ago!
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