J
John949
OK I've registered and thanks to Chris for spotting that it's a thermal store not an unvented system - I understand more of what all the pipes are for now! To recap and elaborate:
My son has just moved into a new flat and this is my first experience of a thermal store!
His problem is that the water is initially very hot but then runs cold quickly - he has to be very fast in the shower, baths are not feasible.
The cylinder is heated by a conventional sealed system boiler (also does the rads) and this appears to be working fine. Selecting hot water causes the 3 way valve to divert hot water into the cylinder, but after about 10 mins the boiler begins to cycle against it's water temperature thermostat (which is set to 4 out of 5) so clearly the primary loop temperature is high but the thermal store thermostat (positioned near the bottom of the tank and appears to be non-adjustable) is still calling for heat.
The case is octagonal and the connections are a bit puzzling to a novice. The primary heating coil is clearly marked but the in /out connections have been reversed - output from 3 way valve goes to the connection marked heating coil outlet (the upper connection). Don't think will make huge difference.
The cold inlet and the hot outlet are in the middle of the tank and about 12 inches apart. I was expecting cold at the bottom and hot at the top! Of course they may go anywhere inside the case. There is also some sort of 'relief valve' (has a twist knob marked + -) between the cold in and hot out - I now know this is a blend valve
There are also two more pipes exiting at the top of the boiler - presumably these are the fill and vent for the header tank?
A stuck ballcock would mean that the store is low on water, but wouldn't the store thermostat still shut off the boiler?
As this is a rented flat I will be keeping my tools in the bag and getting the landlord to fix it, but my curiosity is getting the better of me. I've seen similar problems when a vented system tank gets completely clogged up with calcium deposits and the tank does look quite old.
Any ideas or explanations would add to my education.
My son has just moved into a new flat and this is my first experience of a thermal store!
His problem is that the water is initially very hot but then runs cold quickly - he has to be very fast in the shower, baths are not feasible.
The cylinder is heated by a conventional sealed system boiler (also does the rads) and this appears to be working fine. Selecting hot water causes the 3 way valve to divert hot water into the cylinder, but after about 10 mins the boiler begins to cycle against it's water temperature thermostat (which is set to 4 out of 5) so clearly the primary loop temperature is high but the thermal store thermostat (positioned near the bottom of the tank and appears to be non-adjustable) is still calling for heat.
The case is octagonal and the connections are a bit puzzling to a novice. The primary heating coil is clearly marked but the in /out connections have been reversed - output from 3 way valve goes to the connection marked heating coil outlet (the upper connection). Don't think will make huge difference.
The cold inlet and the hot outlet are in the middle of the tank and about 12 inches apart. I was expecting cold at the bottom and hot at the top! Of course they may go anywhere inside the case. There is also some sort of 'relief valve' (has a twist knob marked + -) between the cold in and hot out - I now know this is a blend valve
There are also two more pipes exiting at the top of the boiler - presumably these are the fill and vent for the header tank?
A stuck ballcock would mean that the store is low on water, but wouldn't the store thermostat still shut off the boiler?
As this is a rented flat I will be keeping my tools in the bag and getting the landlord to fix it, but my curiosity is getting the better of me. I've seen similar problems when a vented system tank gets completely clogged up with calcium deposits and the tank does look quite old.
Any ideas or explanations would add to my education.
