Central heating working but very little hot water

damo3000

Hello,

I have an issue where my gas boiler (non-combi) is heating the rads without issue but there is very little hot water to the taps/shower. Essentially, very little water is flowing out from the cylinder to the hot water pipe that is connected to the pump.

The boiler was serviced last month and around that time, the water did not seem to be fully heating up, maybe to about 80% of it's usual heat. We then had a Climote system fitted last week and since then, the water might get to about 20% of what it used to heat up to (not suggesting the service or Climote caused the issue, just coincidental timings).

The cylinder is an indirect combination unit.

There are two motorised valves (one for rads and one for hot water) and both are working fine from what I can tell (both open when boiler is switched on). The pipes connected to the cylinder for the rads all heat up, but the hot water pipe connected to the pump barely warms up.

The hot taps are flowing at regular pressure with no spluttering, so I assume no air locks and the boiler's pressure is sitting between 1 - 2 bar.

Anyone have any ideas?

Thanks

Damien

TECH85

Possible airlock in coil of cylinder.
Is there an automatic air vent on the flow , theres 2 pipes into side of cylinder, bottom is return back to boiler, top is flow from boiler.
Try the vent if there is one fitted.
Check both of those pipes are getting hot. The top slightly hotter than bottom is normal..

rightjob!

damo3000 wrote: »

Hello,

I have an issue where my gas boiler (non-combi) is heating the rads without issue but there is very little hot water to the taps/shower. Essentially, very little water is flowing out from the cylinder to the hot water pipe that is connected to the pump.

The boiler was serviced last month and around that time, the water did not seem to be fully heating up, maybe to about 80% of it's usual heat. We then had a Climote system fitted last week and since then, the water might get to about 20% of what it used to heat up to (not suggesting the service or Climote caused the issue, just coincidental timings).

The cylinder is an indirect combination unit.

There are two motorised valves (one for rads and one for hot water) and both are working fine from what I can tell (both open when boiler is switched on). The pipes connected to the cylinder for the rads all heat up, but the hot water pipe connected to the pump barely warms up.

The hot taps are flowing at regular pressure with no spluttering, so I assume no air locks and the boiler's pressure is sitting between 1 - 2 bar.

Anyone have any ideas?

Thanks

Damien

Open the balancing valve at the coil one full turn and see what way it heats for a few days.

damo3000

Hi guys,

Thank you both for your responses.

I'm not sure if there is an automatic air vent on the flow. Where would I find that/what would it look like?

The same goes for the balancing valve, where should I see that?

This is what the bottom half of the cylinder looks like...

IMG_20181015_064932.jpg

IMG_20181015_064941.jpg

Damien

damo3000

Ok, just a very quick update. I tried opening the tap coming from the bottom of the cylinder fully and I now have hot water flowing to the showers/taps again! I assume this is the valve you guys were referring to, right?

If so, would this have pushed the airlock through and should it now be closed again? Is there any reason why it would have remained closed for so long without an issue?

Thanks again!

Damien