Halogen Lamp heating system, diversity?

[timhoward]

I'm in the middle of preparing a quote for installing 12 x 3Kw and 4 x 2Kw halogen heaters in a church.
The system design was provided by a specialist company.

This sort of thing:

The system is specified to be split into five zones to be turned on depending on occupancy. Unless the church is packed it's likely only 3 zones will be in use. I'm trying to work out what degree of diversity I can reasonably apply to the total possible load of 44Kw.
I'm currently erring on very little as it seems possible to fire all up 5 zones at once. I'm not yet clear on whether they are thermostatically controlled.

Which leads onto the next topic. I turned everything on (lighting, organ blower, under pew bar-heating which they are retaining, water heaters etc) and measured 45 amps max demand.
The existing supply is a little 'curious'. At present the supplier fuse is unknown but likely 60A and only one phase is connected and metered on the customer side.
There's:
- two phases coming in using newer tails (only one in use)
-a phase coming in using an older cable (not in use)
-the neutral using another older cable.
-One of the fuses in the newer head is linked to another one.
It feels as though something prompted an upgrade but it's curious the Neutral is still an old cable.
I've confirmed all 3 phases are present with 400v between them all.

What I intend to do, unless wisdom from you fine bunch tell me I'm being silly, is ask them to apply for a supply upgrade to the (worst case) 55KVA and seeing what the DNO make of the current setup.

My hunch is that this project will need a 3x100A supply and if phases are carefully balanced that leads to max demand of 80 amps per phase.
Am I over-estimating max demand? The under pew heating is a constant load with just an over-heat safety stat on each unit.

 

[Mikegh]

Never thought of that

Something tells me burst-firing is expensive here ?

 

[timhoward]

That would be something to raise - if they won't allow reinstatement of radiators, how on earth are you going to get permissions for all those radiant heaters ?

At the moment I'm expecting the size of the desktop (darts board generated) quote from Scottish Power to upgrade the supply will come as a surprise and may lead to a reassessment of options.

Conceptually the upgrade probably amounts to 2 new tails and some 100A fuses. However I haven't traced back the many metres of tails (it was dark and I gave up after about 15m when they rose to 5m high clipped to external wall) and I have a feeling that it won't be allowed to be upgraded as it stands without ground works or a span getting bringing things nearer. We'll see.

The faculty application has not yet been submitted and from past experience this will open up a new round of fun.

I've now gently said that until they have approved the supply upgrade costs I won't prepare a quote.
The next stage will be chicken and egg - a detailed enough quote for Listed Building Consent, without spending hours and hours on it...!
The company that designed the proposal have installations in other Gd1 listed churches which helps a bit.

 

[nicebutdim]

Went to investigate and found no less than SIX electric kettles, all used simultaneously and plugged into three 2G sockets, along with a microwave and a small table top oven - all on a 20A MCB. I split the circuit and installed a second 20A feed to half of the sockets, along with a bit of advice on loading.

Given that the heater pictured is designed to heat people using the infra red light spectrum and not the space around them it cannot be controlled via a thermostat
Fitted quite a lot of these back in the late 80's and early 90's mainly in commercial and industrial buildings with some success especially when controlled with PIR / microwave movement detectors and staff / people are moving around, as mentioned

When your sat down in an area and it is difficult to move around you can end up overheating / irritating people

Another thought would be how they may affect any photography or video during weddings or other special occassions given the operating light spectrum of these heaters

Heating churches is always a difficult one especially given the high / vaulted ceilings I have often thought that pasteurisation fans would help push some of the lost heat down but they may not fit in with the character and architecture of the church

I'd initially wondered why this type of heater would be thermostatically controlled, but a quick google informed me that many are. Seems odd, but my assumption is that they'll cut out when the space is heated to the level at which their stat is set. In the case of a open ceiling church I imagine that would take quite some time.

Halogen heating seems to have become very popular and, for the life of me, I can't understand why. Certainly in the case of smoking areas or beer gardens, where there's an insistance on heating the atmosphere, these would provide some warm to bodies. Otherwise I view them as a gimmick initially sold through shopping channels and better buy catalogues, which inexplicably gained popularity.

 

[Vortigern]

Get a pellet stove that will do the trick.

 

[timhoward]

Get a pellet stove that will do the trick.

They are currently running a giant diesel heater!

 

[SparkySy]

They are currently running a giant diesel heater!

A church I do work for ended up using one of those, trouble was it was noisy when running and went cold as soon as it turned off, also a few of the elderly parishioners started to complain about feeling dizzy, so that got switched off. They finally got two new boilers installed and went back to gas.
The pellet boilers are ok, I have a customer who has just had theirs taken out as it kept getting clogged and shutting down, they have just gone ground source as they have a sizeable paddock they could install the loop in.

Churches are usually high and cold places, always expensive to heat and there is no one size fits all option.
Sy

 

[SparkySy]

Looking again at the IR type heaters, I have used them before for commercial applications and they have been very effective, as someone mentioned usually controlled by a Pir or occupancy sensor.
The biggest complaint we use to get was on picking PC stations in cold warehouses, the pickers would stop by the station to swap code readers and get warm then feel colder when they went off picking again.
I can see the point raised above, of those Sat close to them will roast while the further away will feel little benefit.
I have seen fans on heating as @Simon47 describes above installed in a church before, they had to get it all running an hour before it needed to be warm but once working did a good job, they also had heating pipes under the pews to add some upward warmth.
That was oil fired and was a reasonable system. Probably one of the better system I have seen installed in a church so far but not without limitations, if it was really cold for a few days you could feel it creeping into the building.

I think most of these buildings you have to use a variety of methods to heat various different areas within the building.
Some I go to have a right mix of sizes and shaped rooms that all present different challenges!

 

[brianmoooore]

There's a church in a town near me that has solved the heating problem for most days by building what is essentially a large timber and glass conservatory inside the church, which I estimate could seat about thirty people.
I've only ever been inside the place once, and that was for the funeral of a local sparky, who had also been the town mayor. The whole place was packed that day, and it was summer, but after the service I ventured into the 'conservatory', and was impressed. it hardly detracted from the experience of being inside a full size church at all, but I'll guarantee it could be made nice and warm in there in winter.