What do these pipes do?

[*rab*]

Hi all...

I'm not completely clueless about CH systems, and I have read up before asking, but my airing cupboard has got me stuck, and was wondering if someone could explain to me...

It's a gravity-fed open vented system (there's no valves, and the programmer is in 'G' position). The pump's flow direction in the diagram is going right.

Does this look like a normal system? I don't understand what a drayton TRV is doing in there? Why does the pump outlet tee and then go into the cylinder?

Cheers
Rab

 

[ArtfulBodger]

I don't think your diagram really represents what your system actually looks like.

However, the purpose of the thermostatic valve is to regulate the temperature of water entering the heating coil and thus controlling your DHW temperature.

You see them on systems without motorised valves and normally convince the owners to have them upgraded.

Incidentally, it might look like a TRV but costs a lot more.

 

[*rab*]

I don't think your diagram really represents what your system actually looks like.

However, the purpose of the thermostatic valve is to regulate the temperature of water entering the heating coil and thus controlling your DHW temperature.

You see them on systems without motorised valves and normally convince the owners to have them upgraded.

Incidentally, it might look like a TRV but costs a lot more.

Ok - i was confused about the TRV bit - especially considering that it was on a tee fitting. Cheers for clearing that up - But the rest of it - it really does look like that... (i didn't include the stopcocks) - that's what confused me. That's why I asked on this forum.

 

[*rab*]

Why do you say that it doesn't really look like that - because of where the pump is?

 

[ChrisR]

What's confusling me is the apparent pair of pipes going into the top of the cylinder. Is it just like that? Is one the temperature sensor from the TV? (often called Cyltrol valves - black knob?)

 

[*rab*]

What's confusling me is the apparent pair of pipes going into the top of the cylinder. Is it just like that? Is one the temperature sensor from the TV? (often called Cyltrol valves - black knob?)

Umm - that's just what they do - i thought one was supposed to be in the bottom and one in the top. Have a look yourself and see what you think...

 

[keego]

It's a hot rod, there's no coil as such in the cylinder. The hot rod is put in in place of an immersion & converts a direct cylinder to an indirect, it's just a loop of 15mm pipe inside heating the water up.

 

[*rab*]

It's a hot rod, there's no coil as such in the cylinder. The hot rod is put in in place of an immersion & converts a direct cylinder to an indirect, it's just a loop of 15mm pipe inside heating the water up.

Well I don't think I would ever figured that out. I've never heard of one of these. Do you know if this is common? Would it be advisable to change it? Would it explain why our water takes **ages** to heat up, even though the boiler circuit is baking hot?

As that's cleared up, can someone tell me is my pump in the wrong place? Why does the outlet tee and then go to the cylinder and (i presume) the rads both?

 

[chrishutt]

It's a fully thermostatic control system. The hot water temp. is controlled by the 3 port valve in the picture (which moves between DHW coil and by-pass positions - sensor strapped to side of cylinder). The heating circuit will doubtless be controlled by TRVs on the radiators. The only electrical control will be the timer.

Such systems were promoted in the past, particularly by Danfoss, who may still show such a set up on their web site. The "hot rod" was one of a number of immersion boss converter coils available, notably the "Micraversion" (?) by Wednesbury and one by Salamander. I would guess installation is 20+ years old.

 

[*rab*]

It's a fully thermostatic control system. The hot water temp. is controlled by the 3 port valve in the picture (which moves between DHW coil and by-pass positions - sensor strapped to side of cylinder). The heating circuit will doubtless be controlled by TRVs on the radiators. The only electrical control will be the timer.

Such systems were promoted in the past, particularly by Danfoss, who may still show such a set up on their web site. The "hot rod" was one of a number of immersion boss converter coils available, notably the "Micraversion" (?) by Wednesbury and one by Salamander. I would guess installation is 20+ years old.

Sounds like you well know your systems

Right about the age... 1977 it says it was installed. But no on the TRV front - when we moved in there was no TRVs or roomstat, and the hot water was hardwired to the pump. To say it was difficult to control would be a euphemism.

So am I right that the pump is pumping both the HW and CH, but no CH/HW valve? Could it easily be converted to a Heatshare/Y-Plan system you reckon?

 

[leakydave]

It looks to me as if its time to upgrade to foamed cylinder and more conventional system design...

what do you reckon? Am I being unromantic about your 'hot rod system' (that I'd never even heard of until now)

£££?