Replacement combi for UFH installation help needed LONG POST

[matt1e]

hi don't if this will help but here go's
all the ufh systems I have worked on (and it ain't that many) have been on the same estate and used the same control systems
that consisted of a

dedicated control unit (cant remember the make)
8 port manifold with powered heads
room stat in every room
a secondary pump
a (3 port I think) thermostatic mixing valve with a capillary connected to the manifold
a pipe stat

basically the roomstats controlled the heating in each zone
via the control box ie stat one would open actuator 1 etc
the secondary pump was used to recirculate the useful heat in the underfloor pipes when the boiler and its pump was shut down via boiler stat or flow shut off by thermostatic valve
this recirculation was controlled by the thermostatic valve which regulated the flow from the boiler
there was also a bypass fitted and (I think) set to bring the return back up to a useful temp to preserve the HEX but this may have been controlled by the thermostatic valve cant really remember
cant remember if the pipe stat was fitted on the flow or return but it was wired as a overheat stat cutting off all power to the controller at a certain temp
sorry bit vague I know but it may help

matt

 

[EliteHeat]

I think I'd run a mile looking at the state of that pipework and wiring. If something goes wrong you'ld struggle like hell to work out what's going on.

Mike

Yes, it does look rubbish doesn't it.

 

[EliteHeat]

hi don't if this will help but here go's
all the ufh systems I have worked on (and it ain't that many) have been on the same estate and used the same control systems
that consisted of a

dedicated control unit (cant remember the make)
8 port manifold with powered heads
room stat in every room
a secondary pump
a (3 port I think) thermostatic mixing valve with a capillary connected to the manifold
a pipe stat

basically the roomstats controlled the heating in each zone
via the control box ie stat one would open actuator 1 etc
the secondary pump was used to recirculate the useful heat in the underfloor pipes when the boiler and its pump was shut down via boiler stat or flow shut off by thermostatic valve
this recirculation was controlled by the thermostatic valve which regulated the flow from the boiler
there was also a bypass fitted and (I think) set to bring the return back up to a useful temp to preserve the HEX but this may have been controlled by the thermostatic valve cant really remember
cant remember if the pipe stat was fitted on the flow or return but it was wired as a overheat stat cutting off all power to the controller at a certain temp
sorry bit vague I know but it may help

matt

So, would that 3PV be a blending thing then? Are those white doodahs powerheads? if so, presumably a number of them would be controlled by a single stat - there is an upstairs and downstairs one.

If that is the case, I can just quote for two new programmable stats, a new pump and replacement boiler.

 

[Norcon]

What's a 'U' plan pray tell?

See pages 10 and 11 of Honeywell Wiring Guide

Thanks for the link. Very informative.
I've fitted a few of Bassets systems and they don't use zone valves.
The thermic actuaters on the manifold are the zoning control.
Rehau use zone valves along with the thermic actuaters in their design.
The system without the zone valves will have a dedicated controller with output relays to the secondary and primary pumps and these will only energise after a delay to allow the actuaters to open. Typical delays could be 180 seconds for the secondary pump and 190 seconds for the primary pump as in the Rehau system.
This prevents the pump dead heading though in reality this does not cause serious problems. In older systems they usually left a loop open to act as a by-pass.


The OP's system might be the older Wirsbo system which uses an OJ Electronic controller ETZ which is like a heating / DEAD BAND/cooling thermostat.
Its was fitted along with a Drayton TA/M5 divertor actuater afaik.
Though I don't see any sign of a controller in the images.
Probably not much help to the OP.
Would run a mile if I came on that menargie of a mess also.

 

[Dick Puller]

Hmmmmmmmmmmmmmmm!!!!!!!!!!!! Nice!!!!
Ahahahahahaha!!!
Eh err sorry luv, I've a lot of work on at the moment, wouldn't be able to do anything for you for weeks!!!

 

[Dick Puller]

older Wirsbo system...........

Looks like a Hep system that some cowboy throw in from 33,000 feet!!

That has got to be the worst install I've seen in years, they should use it on CC courses, as a spot the mistakes contest!!!

 

[Norcon]

Todger tugger, the pipe from the manifold looks like hep yes.
That doesn't say it doesn't have the old OJ control set up that wirsbo commonly used. Unlikely but you never know.
Have you ran out of ccc's/cc's to wind up over on skrewbroke.com?

 

[matt1e]

So, would that 3PV be a blending thing then? Are those white doodahs powerheads? if so, presumably a number of them would be controlled by a single stat - there is an upstairs and downstairs one.

If that is the case, I can just quote for two new programmable stats, a new pump and replacement boiler.

hi elite
As said i'm not the best to advise on this but yes I think the 3pv looks like it could be the blending control though I would expect it to be thermostatically controlled maybe Norcon can advise better
The white "doodahs" were indeed power heads on the systems I worked on and if I remember correctly they were 230v so yes they could be controlled by a stat - but they may be thermostatic if so the norm is to supply with a two port which also fires the boiler

I think I would be tempted rip that lot out and quote for a new manifold kit too as some come complete with pump,blending valve,gauge,etc but they're not cheap so up to your customer I suppose

Heres a link to one manufacturer with some wiring etc dont worry if the system seems slightly different to yours as they all seem to differ slightly but it might give you a few pointers

http://www.begetube.co.uk/assets/applets/BEGETUBE_TECHNICAL_MANUAL_2006_WEB.pdf

matt