Central Heating controller for multiple zones?
 

I'm trying to find a central heating controller for multiple zones.

I have an underfloor heating system, which leaks. (It's an old (~10 years)
Nu-Heat system with Contraflo rubber hoses. They don't use that material
anymore, but that doesn't stop mine rotting - so far mostly at the manifolds,
but it's going to spread.)

I am planning to replace upstairs with radiators, because I can't cope
with the idea of taking down every downstairs ceiling in order to fit
underfloor heating (nor of taking up all the carpets, routing grooves
in the T+G chipboard for new pipes, putting a hardboard floor on top of
that and taking a bit off all the doors to allow for the raised floor).

(Downstairs i) isn't leaking yet and ii) is wood block floor which is
easier to take up to get at the pipes, so the current plan is to keep
that as underfloor, replacing with new style pipes next summer.)

I did get a plumber in to quote for doing the radiator conversion,
but since he didn't pay attention and only quoted for half the job,
and given the amount of time I've spent fixing other plumbers work
in the past, I decided to do it myself.

At the moment upstairs has three heating zones, each with a Danfoss TP5
5/2day programable thermostat connected to the central control box,
which controls the zone valves at each manifold, and switches the
heating circuit pump when any zone thermostat switches, and is supposed
to switch the boiler pump when the cylinder thermostats switch, but
actually runs it the whole time at the moment (so the cylinder temperature
is actually set by the boiler thermostat - not ideal).

(The cylinders (two, paralleled) are thermal store types:
http://www.diyfaq.org.uk/plumbing/he...s.html#thermal
(except they are a sealed circuit, not open vented).)

What I would like, or at least what I think I would like, is to leave
the existing controller switching just the underfloor heating circuit
pump (based on the downstairs zone thermostats), and keep the upstairs
zone thermostats with two-port zone valves and a controller that will
switch the boiler circuit pump if any of the zones or the cylinder
thermostats are calling for heat.
Explaining this to local plumbing supplies results in quite a lot of
blank looks (having spent 15 minutes explaining the existing system
to a plumber with both a schematic and the actual pipework in front
of us before he finally got it, this didn't surprise me).
The Danfoss and Honeywell brochures I have only cover simple systems.

Any suggestions? A Danfoss FH-WC looks like it might do the job, is
there any reason not to use it for radiators rather than underfloor
zones? (http://tinyurl.co.uk/n4nk)

Central Heating controller for multiple zones?
 

"Alan Braggins" wrote in message
...
I'm trying to find a central heating controller for multiple zones.

I have an underfloor heating system, which leaks. (It's an old (~10 years)
Nu-Heat system with Contraflo rubber hoses. They don't use that material
anymore, but that doesn't stop mine rotting - so far mostly at the
manifolds,
but it's going to spread.)

I am planning to replace upstairs with radiators, because I can't cope
with the idea of taking down every downstairs ceiling in order to fit
underfloor heating (nor of taking up all the carpets, routing grooves
in the T+G chipboard for new pipes, putting a hardboard floor on top of
that and taking a bit off all the doors to allow for the raised floor).

(Downstairs i) isn't leaking yet and ii) is wood block floor which is
easier to take up to get at the pipes, so the current plan is to keep
that as underfloor, replacing with new style pipes next summer.)

I did get a plumber in to quote for doing the radiator conversion,
but since he didn't pay attention and only quoted for half the job,
and given the amount of time I've spent fixing other plumbers work
in the past, I decided to do it myself.

At the moment upstairs has three heating zones, each with a Danfoss TP5
5/2day programable thermostat connected to the central control box,
which controls the zone valves at each manifold, and switches the
heating circuit pump when any zone thermostat switches, and is supposed
to switch the boiler pump when the cylinder thermostats switch, but
actually runs it the whole time at the moment (so the cylinder temperature
is actually set by the boiler thermostat - not ideal).

(The cylinders (two, paralleled) are thermal store types:
http://www.diyfaq.org.uk/plumbing/he...s.html#thermal
(except they are a sealed circuit, not open vented).)

What I would like, or at least what I think I would like, is to leave
the existing controller switching just the underfloor heating circuit
pump (based on the downstairs zone thermostats), and keep the upstairs
zone thermostats with two-port zone valves and a controller that will
switch the boiler circuit pump if any of the zones or the cylinder
thermostats are calling for heat.
Explaining this to local plumbing supplies results in quite a lot of
blank looks (having spent 15 minutes explaining the existing system
to a plumber with both a schematic and the actual pipework in front
of us before he finally got it, this didn't surprise me).
The Danfoss and Honeywell brochures I have only cover simple systems.

Any suggestions? A Danfoss FH-WC looks like it might do the job, is
there any reason not to use it for radiators rather than underfloor
zones? (http://tinyurl.co.uk/n4nk)

I can't see what your problem is. The existing controllers and room stats
will be OK ro use with UFH or rads. You are replacing the upstairs UFH with
rads, so depending on who many zones upstairs you use a controller to suit.

Central Heating controller for multiple zones?
 

The message
from (Alan Braggins) contains these words:

At the moment upstairs has three heating zones, each with a Danfoss TP5
5/2day programable thermostat connected to the central control box,
which controls the zone valves at each manifold, and switches the
heating circuit pump when any zone thermostat switches, and is supposed
to switch the boiler pump when the cylinder thermostats switch, but
actually runs it the whole time at the moment (so the cylinder temperature
is actually set by the boiler thermostat - not ideal).

You don't need another controller if you have the programmable
thermostats wired up properly. IIRC the thermostat controls the zone
valve and the zone valve controls the boiler just as it would if you
only had one zone.

My experience is with radiators but I don't see why the basic controls
for underfloor heating should be different. (I only have 2 heating
zones. Downstairs controlled by a TP75 and upstairs by a cheapo from
Screwfix.)

--
Roger Chapman

Central Heating controller for multiple zones?
 

Doctor Drivel wrote:

I can't see what your problem is. The existing controllers and room stats
will be OK ro use with UFH or rads. You are replacing the upstairs UFH with
rads, so depending on who many zones upstairs you use a controller to suit.

The existing controller won't switch the boiler/radiator pump based on
the room thermostat input, only the underfloor heating circuit pump.
I'm not running the radiators off the existing heating circuit because
the radiators need to be hotter, and the existing underfloor heating
hoses aren't compatible with steel.

Central Heating controller for multiple zones?
 

In article , Roger wrote:
The message
from (Alan Braggins) contains these words:

At the moment upstairs has three heating zones, each with a Danfoss TP5
5/2day programable thermostat connected to the central control box,
which controls the zone valves at each manifold, and switches the
heating circuit pump when any zone thermostat switches, and is supposed
to switch the boiler pump when the cylinder thermostats switch, but
actually runs it the whole time at the moment (so the cylinder temperature
is actually set by the boiler thermostat - not ideal).

You don't need another controller if you have the programmable
thermostats wired up properly.

I could replace the existing controller rather than add to it, but
I don't think it's going to work with just the existing controller -
the logic needs to change for the new circuit.

Central Heating controller for multiple zones?
 

"Alan Braggins" wrote in message
...
Doctor Drivel wrote:

I can't see what your problem is. The existing controllers and room stats
will be OK ro use with UFH or rads. You are replacing the upstairs UFH
with
rads, so depending on who many zones upstairs you use a controller to
suit.

The existing controller won't switch the boiler/radiator pump based on
the room thermostat input, only the underfloor heating circuit pump.
I'm not running the radiators off the existing heating circuit because
the radiators need to be hotter, and the existing underfloor heating
hoses aren't compatible with steel.

You have the controller activate a zone valve or a relay. The end switch on
the zone valve switches the pump, or the relay switches the pump. A stab
can be in series to activate the relay or zone valve. Depending on how the
store in configured, the boiler operates independently on the store. Some
have the top switch by a DHW timeclock, and the bottom by a CH
controller(s). The CH controller switches in the CH section of the store
(boioer control) via time section of the controller. The CH pumps (or pumps
and zones valves) by the stats.

You need to think out the logic.

Boiler control - CH zones
Boiler control - DHW
CH control - zones
CH control - zones by stats

Central Heating controller for multiple zones?
 

Alan Braggins wrote:
I'm trying to find a central heating controller for multiple zones.

I have an underfloor heating system, which leaks. (It's an old (~10 years)
Nu-Heat system with Contraflo rubber hoses.


Santoprene (rubber) was the pipes that were the triple pipe contraflow
system ... originally sold & rights owned by Kee,
(http://www.keeheating.co.uk/) Nu-Heat were the UK agents for them.
When Nu-Heat went their own way they continued with twin pipe variant,
before swapping to Pex pipe.

Nu-Heat were advertising a 30yr warranty of Santoprene pipes, as long
as it was run with a Thermal store and at the correct 'warm' rather
than hot. (hence 'warm water underfloor heating')
Have you contacted Nu-Heat over this, worth trying ?


I have a 17 zone Nu-Heat system (pex) and found them a great company to
deal with, with good after sales service.

Rick

Central Heating controller for multiple zones?
 

The message
from (Alan Braggins) contains these words:

You don't need another controller if you have the programmable
thermostats wired up properly.

I could replace the existing controller rather than add to it, but
I don't think it's going to work with just the existing controller -
the logic needs to change for the new circuit.

Sorry, you have lost me. What logic? And in what way do your zone valves
differ from the bog standard 2 port zone valve?

You say in reply to Dribble (who lives in my killfile) "The existing
controller won't switch the boiler/radiator pump based on the room
thermostat input" but on my system the controller doesn't either. The
central heating is set to permanently on and the boiler controlled via
the microswitch on the zone valve which is itself controlled by the
programmable stat.

--
Roger Chapman

Central Heating controller for multiple zones?
 

In article , Roger wrote:
The message
from (Alan Braggins) contains these words:

I could replace the existing controller rather than add to it, but
I don't think it's going to work with just the existing controller -
the logic needs to change for the new circuit.

Sorry, you have lost me. What logic?

Of what gets switched when. At the moment the heating circuit runs off
the thermal store, and the boiler is independent. But the radiators
won't be running off the thermal store, so switching the underfloor
heating pump on won't do anything to the radiators.


And in what way do your zone valves
differ from the bog standard 2 port zone valve?

As it happens they are an unusual design, but I think that's irrelevent.


You say in reply to Dribble (who lives in my killfile) "The existing
controller won't switch the boiler/radiator pump based on the room
thermostat input" but on my system the controller doesn't either. The
central heating is set to permanently on and the boiler controlled via
the microswitch on the zone valve which is itself controlled by the
programmable stat.

"the zone valve" implies you only have one. I have three zones, and want
the boiler controlled by any one of them (or the cylinder thermostats).
I could have a wire going all round the house with the AUX contacts of
the valves in parallel, or I could have a central controller that does
it all neatly. I'm hoping for the latter.

Nu-Heat leaking underfloor heating ( Central Heating controller for multiple zones?)
 

In article om, Osprey wrote:
Alan Braggins wrote:
I'm trying to find a central heating controller for multiple zones.

I have an underfloor heating system, which leaks. (It's an old (~10 years)
Nu-Heat system with Contraflo rubber hoses.
[...]
Have you contacted Nu-Heat over this, worth trying ?

Yes. They offered a discount on a replacement system, and blamed Monsanto
for selling them unsuitable material with false promises. I'm not the
original house builder who had it installed.

(The materials cost for the replacement system is less than the cost
of radiators, but the work involved in getting it under the floor
would be huge. It was bad enough getting at a leak at one point under
a bathroom floor where the heating hose was resting on the then-unlagged
boiler pipe (luckily we wanted to take the carpet up anyway, but having
now laid tiles I'd rather not have to take them up).)

http://www.ebuild.co.uk/forums/messages/3322/6281.html has some other
peoples' experience. (The Nu-Heat engineer who came to see our system
also said that he'd seen the same problem in other Nu-Heat systems of
similar age.)

(They have been helpful with spare parts for fixing the leaks, and advice.
Last time they warned me they were running short of replacement hose
material.)

Nu-Heat leaking underfloor heating ( Central Heating controller for multiple zones?)
 

The message
from (Alan Braggins) contains these words:

Yes. They offered a discount on a replacement system, and blamed Monsanto
for selling them unsuitable material with false promises.

It's still their problem though. They may choose to take it up with
Monsanto, but that's a different matter.

--
Skipweasel
Pay no attention to that man behind the curtain.

Central Heating controller for multiple zones?
 

In article , Alan Braggins wrote:
I could have a wire going all round the house with the AUX contacts of
the valves in parallel

P.S. or I could if I swapped some of the valves - the originals don't
have the extra contacts, but the replacements for a couple of failed
ones do.

Central Heating controller for multiple zones?
 

Alan Braggins wrote:
I'm trying to find a central heating controller for multiple zones.

Try this lot;
http://www.kanmor.com/kaneng.html

Tekmar controllers, US (bigger houses, many zones) company. Maybe
contact Tekmar in the US detailing how many zones you want & the other
bells & whistles and ask them to recommend a controller. Never used
them, but they're reputedly very good.

Failing that, a UK BMS (programmable controller) contractor could
construct whatever you need, but BMS is aimed at comercial stuff & have
commercial prices (e.g., cheapest PC interface program £400 ish,
hardware extra) .

Nu-Heat leaking underfloor heating ( Central Heating controller for multiple zones?)
 

Owain wrote:
Guy King wrote:
Yes. They offered a discount on a replacement system, and blamed Monsanto
for selling them unsuitable material with false promises.
It's still their problem though. They may choose to take it up with
Monsanto, but that's a different matter.

But the contract of sale is with the original housebuilder (and would
have been a trade contract, allowing exclusions from consumer law) and
not with the current householder.

Owain

It would be worth looking at original contract, many 'warranties' are
transferable, which might assist you.

Central Heating controller for multiple zones?
 

The message
from (Alan Braggins) contains these words:

And in what way do your zone valves
differ from the bog standard 2 port zone valve?

As it happens they are an unusual design, but I think that's irrelevent.

That depends on whether or not they have the normal functions.

You say in reply to Dribble (who lives in my killfile) "The existing
controller won't switch the boiler/radiator pump based on the room
thermostat input" but on my system the controller doesn't either. The
central heating is set to permanently on and the boiler controlled via
the microswitch on the zone valve which is itself controlled by the
programmable stat.

"the zone valve" implies you only have one. I have three zones, and want
the boiler controlled by any one of them (or the cylinder thermostats).
I could have a wire going all round the house with the AUX contacts of
the valves in parallel, or I could have a central controller that does
it all neatly. I'm hoping for the latter.

No I have 2 zones (as I said in my previous post). I don't know about
the TP5 but with the TP75 and normal zone valves you can wire them so
the thermostat switches the zone valve and the zone valve switches the
boiler. In theory you could have any number of separate zones.

--
Roger Chapman

Nu-Heat leaking underfloor heating ( Central Heating controller for multiple zones?)
 

In article . com, Osprey wrote:
Owain wrote:
Guy King wrote:
Yes. They offered a discount on a replacement system, and blamed Monsanto
for selling them unsuitable material with false promises.
It's still their problem though. They may choose to take it up with
Monsanto, but that's a different matter.

But the contract of sale is with the original housebuilder (and would
have been a trade contract, allowing exclusions from consumer law) and
not with the current householder.

It would be worth looking at original contract, many 'warranties' are
transferable, which might assist you.

It was a self-build, so _might_ have been a retail not trade contract.
But they (allegedly, according to village gossip) left for Canada leaving
a lot of debts and taking some money that wasn't strictly theirs. We bought
the house from the people who bought it from them (and have had bailiffs
chasing their debts too).
So if Nu-Heat aren't volunteering it, my chances of finding the original
contract are small.

(Given that I don't have a contract and have no evidence of a warranty,
I haven't bothered asking a solicitor. Maybe I should.)

Central Heating controller for multiple zones?
 

In article , Roger wrote:
from (Alan Braggins) contains these words:

And in what way do your zone valves
differ from the bog standard 2 port zone valve?
As it happens they are an unusual design, but I think that's irrelevent.
That depends on whether or not they have the normal functions.

Most of them don't have switches, just two motor wires. But that can be
changed.


"the zone valve" implies you only have one. I have three zones, and want
the boiler controlled by any one of them (or the cylinder thermostats).
I could have a wire going all round the house with the AUX contacts of
the valves in parallel, or I could have a central controller that does
it all neatly. I'm hoping for the latter.

No I have 2 zones (as I said in my previous post). I don't know about
the TP5 but with the TP75 and normal zone valves you can wire them so
the thermostat switches the zone valve and the zone valve switches the
boiler.

That might be the answer. I'm almost certainly going to have to move some
of the valves, so can't use the existing motor wiring, so can add new
switch wiring that way. To the existing controller even, if I can work
out why it isn't switching the boiler at the moment, just add more inputs
in parallel with the existing cylinder thermostat inputs.

(I did find http://www.cm-zone.com/, which would give switching on individual
radiators, but the price adds up rather.)