Hi,
Today is day#1 of our 4-day boiler replacement & CH overhaul. Plumber doing all the "wet" side, I'm supplying the HA control stuff.
Our plumber leaves the electrics bit to his a colleague who will be here on day #4 to wire up. In the meantime, the plumber (who freely says he doesnt know the elec side of it - he leaves it to the spark) is questioning how our planned way of doing things will interlock with the boiler.
I suspect this is because what we want is just a bit different (more sophisticated) than normal ....
If this is really so, all is not lost because I have a couple of days to get the conventional bits to keep everyone happy, but meantime I'm hoping to get some comments from your knowledgable people...
What is planned is based on the "old fashioned" zone valve & room stat approach, but with multiple zones and idratek relays replacing the "switching" part of a room stat. The live supply side of the idratek relay will be fed from a traditional timer (*), making the system even more analagous to a conventional one.
I was planning to get it wired as follows:
Time switched supply for each zone from the conventional timer/programmer;
Fed into the live side of one idratek relay per zone;
(Switched) Output from Idratek relays connected to motor drive on zone valve (one per zone);
Microswitch contacts on each zone valve connected to boiler's call-for-heat (contacts fed from perm live)
With all live/neutral connections coming from a single FCU (ie one point physical isolation and circuit protection).
I realise the call-for-heat could be driven directly by another Idratek relay (agregating the multiple zone requests) but figured that I may as well use the zone valve microswitches because (1) they are there (2) greater similarity with conventional systems (3) physical interlock instead of logical interlock.
Does anyone see a problem with this ?
Or am I right in thinking the plumber is just being cautious?
(*) as a first step.... as with many other HA HVAC, intention is to bypass this later on...
Today is day#1 of our 4-day boiler replacement & CH overhaul. Plumber doing all the "wet" side, I'm supplying the HA control stuff.
Our plumber leaves the electrics bit to his a colleague who will be here on day #4 to wire up. In the meantime, the plumber (who freely says he doesnt know the elec side of it - he leaves it to the spark) is questioning how our planned way of doing things will interlock with the boiler.
I suspect this is because what we want is just a bit different (more sophisticated) than normal ....
If this is really so, all is not lost because I have a couple of days to get the conventional bits to keep everyone happy, but meantime I'm hoping to get some comments from your knowledgable people...
What is planned is based on the "old fashioned" zone valve & room stat approach, but with multiple zones and idratek relays replacing the "switching" part of a room stat. The live supply side of the idratek relay will be fed from a traditional timer (*), making the system even more analagous to a conventional one.
I was planning to get it wired as follows:
Time switched supply for each zone from the conventional timer/programmer;
Fed into the live side of one idratek relay per zone;
(Switched) Output from Idratek relays connected to motor drive on zone valve (one per zone);
Microswitch contacts on each zone valve connected to boiler's call-for-heat (contacts fed from perm live)
With all live/neutral connections coming from a single FCU (ie one point physical isolation and circuit protection).
I realise the call-for-heat could be driven directly by another Idratek relay (agregating the multiple zone requests) but figured that I may as well use the zone valve microswitches because (1) they are there (2) greater similarity with conventional systems (3) physical interlock instead of logical interlock.
Does anyone see a problem with this ?
Or am I right in thinking the plumber is just being cautious?
(*) as a first step.... as with many other HA HVAC, intention is to bypass this later on...
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