Recommendations for Village Hall

We've been referred here by a friendly refrigeration engineer for advice on heating (and cooling) our Village Hall... and specifically to get an idea of what size budget we might need to be setting for fundraising and grant-writing.

The Hall dates from the 1840s and is a standard, clay lump (thick walled) former school-building (single room, currently single glazed) measuring approximately 12m x 6m (4m ceiling, insulated) with cupboards / toilets / a kitchen off to the side (2.4m wide, 2.1m high extensions along one side and one end).

Heating is currently by 14 x 1.5KW radiant heaters (drawing on 3 phase, 60 Amp supply): this was installed as suitable for a Hall with occasional use... but the Hall is now commonly used from 9.00am-3pm (Playgroup) and from 7pm-10pm (community use) and we've been getting through up to 130KwH PER DAY!!!!

Our friendly engineer says installation of any number of ceiling mounted cassette units (or of 2-3 wall mounted units) would be pretty straightforward but wasn't sure how many we'd need... what specification we'd need... or what this sort of solution would cost.

We could do with a very rough idea of cost to throw into the discussions at a meeting this coming Tuesday evening - suggestions welcome!

First of all,
Here in UK the cheapest way of heating is by using gas fired appliances.
(The gas is just too cheap compared to electricity. How long this will be the case is anybody's guess and heat-pumps will be greener, how much this is worth I leave up to you)
Generally a hall measuring 12x6m would have 2 gas fired space heaters, one in each end. This set up will give the lowest running costs here in UK.

If you then requires cooling in the summer months, I would still recommend gas fired heaters and then 2 A/C units.
Let's look at some figures....
12x6= 72m2
72x150=10.800 (150w/m2)

So, as a minimum (site visit and "proper" calculations are required) you are looking at 10kW of cooling capacity, this does not allow for rapid cooling (i.e. if you arrive to the hall at 3pm on a hot summer day and start an event 15min later and want to quickly reduce the temperature).

If the hall looks anything like I envisioned it, I would recommend that you install 2 one way blowing under ceiling units,one in each end of the hall. Each unit with a minimum cooling capacity of 7kW.


Costs:
(BUT SEE MY NOTE ABOVE ABOUT SITE VISIT)

Space heaters ------ ~£4.000 each
A/C systems -------- ~£3.000 each

It is possible to get reversing A/C systems that would provide heating as well as cooling (Heatpumps) but the running costs will be higher than the gas fired option.


P.S. Have a look at my website www.the-viking.eu click on [air conditioning] then [end users enter here], lots of useful tips there for people in your situation.

Hi All

I would agree with the Viking 10.8 kw sensible cooling.
A site visit is essential to determine exact requirements and correct selection of equipment to suit the application.
Hope this helps

Regards


PP

That's great feedback... though I've one obvious concern: we're miles from anywhere and have no access to mains gas - does that change anything? Is a tank of propane significantly more economical than heat pumps? And what heat output you'd get from space heaters costing approx. £4,000 each?

I'd still appreciate some indication of the cost of reversible units as a means of heating that space: as we're a registered charity and provide community use we may actually find funding "green" heat pump technology rather easier than funding something more conventional.

Grant-giving bodies tend to like that sort of thing.... even if the running costs don't make sense!

Would 2 x 7kW reversible units be suitable as a primary source of heating? I'm assuming we'd need more capacity for heating than for cooling given that the inside to outside temperature differential in winter could be far greater.

ps. I take it a 7kW reversible unit costs rather more than a dedicated cooling unit....

pps. I'm also assuming that £3,000 / unit is "fitted": if not, my fundraising and grantwriting targets need revising upwards rather a lot!

OK,

That changes the balance a bit.
LPG heaters will still be cheaper to run compared to electrical heat-pumps, but only marginally so. Which would mean that the cost for the installation of the heaters would take many years to recoup...Assuming you do need cooling.

A Heat-pump system will save money on your heating bill but remember that it will cost you a similar amount to run them for cooling in the summer. Therefore you might not save any money at all, compared to your current heaters.
Locked controls and some thoughtful set up will assist in reducing the energy bills. For example, if you set the system up to heat to 21 degrees in the winter and cool to 26 degrees in the summer, most people would be happy AS LONG AS THEY DON'T THINK THERE IS AN OPTION!

As a rough guide, a 7kW A/C "Heat-Pump" system would provide 10.5 kW of heating.
(But this is fan assisted and therefore more efficient than your old radiating heaters)
It is worth to remember that this capacity will be reduced as the ambient temperature drops but with the average winters we currently experience here in UK this will not be an issue.

The cost for under ceiling units, as I mentioned in my previous post starts in the region of £3.000 each, installed +Electrical supply ~£700. (Even if they are reversible heat-pumps).

Without having seen the job, I would say allow ~£7.500 + VAT, in total, for budget purposes.


To get accurate figures, both on capacities and costs, you will need to get a reputable contractor to visit site and give you a proper quote.

When you get to the point of placing an order make sure that your new systems are inverter driven and operates on a gas called R410a. Also, considering the usage, make sure they been designed for a commercial market. (See my website for further explanation of this)
Good luck,

Hi Greg,
I take it that Heating is the main requirement, and airconditioning/cooling secondary to the equation, but possibly "nice to have".

Do you / does your electricity supplier offer a night rate tarrif? Could it possibly be cheaper to put in night storage heaters and improve the building insulation. The existing heaters then become boost heaters, mainly for evening use.
The commercial storage heaters have fans for delivery of the heat which is easy controlled by programmable thermostats.

I have installed such heaters for a playgroup which started using a cricket club pavillion and clubhouse. We used pre-insulated plasterboard to line the walls, which was easy to finish. (All the big rigid insulation companies offer similar products eg. Kingspan, Celotex, Knauf).
The increased insulation lowered the heat loss and ongoing running costs, and made it possible for storage heaters to meet the requirements (only on single phase supply).
Single glazed windows can be improved with secondary glazing.

I think LPG might work out more expensive than electricity. Access for tanker? Site for tank?

The other costs to consider are maintenance and repair costs. Although I am pro-airconditioning for energy efficiency, they do require regular maintenance to keep them in warranty and also working correctly, and a compressor on a large unit can set you back somewhere up in the high hundreds.

If you do go down the AC route, it would be better to go for x2 (or more) smaller independant units in order to give you redundancy in case of a breakdown, especially when the playgroup are relying on heat! (Although the existing heaters might still be operational, in which case the last point could be ignored, however smaller systems could work out cheaper!)

Have just picked up on Vikings last post. As you're a charity, you should get charged VAT at 5% on Heatpumps...not 17.5%. Something else to consider!

Edit: Reply to "The Viking"...

OK... this sounds like an excellent solution. Two x 10.5 kW heat pumps could consume as much electricity as all 14 of our radiant heaters... but if my reading of heat pumps is right the efficiency could be hugely improved.

Even allowing for a few weeks of every year when the ambient temperature is just too low for maximum efficiency... we might be looking at 2-3 times more heat-input from the same electricity consumption... but I'm wondering if the actual efficiency gain will be even greater given that we're replacing radiant heaters.

A lot will presumably depend on us maximising bulk-heat loss through drafts (and on us replacing the windows)... but losing air-temperature due to cold walls and draughts still strikes me as more efficient than using running radiant heaters that merely heat the walls, floor and fittings to the point where air passing by them warms up.

I'm not exactly confident in my thinking here...but could I suggest to my committee that our energy savings should be at least 50% and quite possibly better than 75%?

Hmm,
Right thought but wrong maths....

14 of 1.5kW heaters will consume 21kWh per hour when working flat out.

2 of 7 kW A/C heat-pumps when working in heating mode, will produce ~21kW of heat, they will consume roughly 7kWh of electricity per hour when working flat out.
(This is on the conservative side, most manufacturers are claiming higher COPs/higher savings)

Your energy saving should be about 66%.
Or, to put it in context, your electricity consumption would drop from 130kWh/day to about 43kWh/day, all things being equal. (There are also other savings by using a fanned system, blowing from high level)

Assuming an electricity cost of 10p/kWh, that's a whooping saving of £8.70 every day you are using the heating.
(But see my post about summer use above)

Quote:

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Originally Posted by Electrocoolman

I take it that Heating is the main requirement, and airconditioning/cooling secondary to the equation, but possibly "nice to have".

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Yup. Clay lump buildings seem to be pretty thermally-efficient, and short periods of extreme hot weather are not a huge problem. On the other hand, our 2-5 year olds have very little access to shade in the outside area... the option of a cool interior would be a pleasant one!

Quote:

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Originally Posted by Electrocoolman

Do you / does your electricity supplier offer a night rate tarrif?

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We currently have a 15.24 / 13.9p / kwh rate from 7am-7pm on weekdays (higher for 1st 750 units / quarter)... and pay 7.6p / kWh the rest of the time.

Quote:

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Originally Posted by Electrocoolman

Could it possibly be cheaper to put in night storage heaters and improve the building insulation [...] We used pre-insulated plasterboard to line the walls, which was easy to finish [...] The increased insulation lowered the heat loss and ongoing running costs, and made it possible for storage heaters to meet the requirements (only on single phase supply).

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Certainly seems possible. I suspect our basic insulation levels (though not draught-proofing) are pretty high anyway... but I've no figures for clay lump walls... and there's still the issue of "greener" heat-pumps being more attractive to grant-giving bodies...

Quote:

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Originally Posted by Electrocoolman

Single glazed windows can be improved with secondary glazing.

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We mayhave to resort to that.... but the case for replacing the crittal windows with wooden windows is reasonable so we're still hopeful of getting funding for this.

Quote:

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Originally Posted by Electrocoolman

I think LPG might work out more expensive than electricity. Access for tanker? Site for tank?

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All feasible enough...

Quote:

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Originally Posted by Electrocoolman

The other costs to consider are maintenance and repair costs.

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Any suggestions on what we'd need to budget on a year by year basis? Assuming 2 units as suggested above...

Quote:

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Originally Posted by Electrocoolman

If you do go down the AC route, it would be better to go for x2 (or more) smaller independant units in order to give you redundancy in case of a breakdown, especially when the playgroup are relying on heat! (Although the existing heaters might still be operational, in which case the last point could be ignored, however smaller systems could work out cheaper!)

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I suppose the radiant heaters should last pretty much indefinitely even if rarely used... so could be retained. We'd perhaps need a switching arrangement to ensure they were not ALL used at the same time as the other heaters... but retaining a backup / aixilliary system strikes me as a very good idea.

Quote:

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Originally Posted by Electrocoolman

Have just picked up on Vikings last post. As you're a charity, you should get charged VAT at 5% on Heatpumps...not 17.5%. Something else to consider!

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Ah.. I'd not realised that: great news! I wonder if we could pay the same rate on replacing our consumer units if we wrote it up as part of "rewiring associated with providing heating" :)

Maintenance costs?

That will vary a lot across the country.
If you are willing to clean the filters monthly yourselves then you should be able to get a maintenance contract from a local company for about £300 per year.

OK... doing a bit to help ourselves is not a problem (we managed about £20,000 worth of refurbishment work for peanuts with 40+ volunteers last summer)... but £300 / year is a significant sum.... and I'm now wondering about replacement schedule.

How long would we go before having to find another ~ £7,500+ vat? We should build that into our costings!!!

The systems should last well over 10 years if of good manufacture, correctly installed and well maintained.

Ok... 10 years to raise £7,500 means £750 / year.... and a service contract of £300 / year takes us into 4 figures.

Our savings on electricity might be in the order of... just a little more than that amount - net gain... we'd be greener, we'd have draughts instead of all or nothing radiant heat, we'd have air-con where we had none... but the finances would not be hugely affected!

I'm still up for it... but the savings suddenly start looking less impressive given that maintenance of radiant heaters seem to amount to just about nothing and seeing as they appear destined to live forever unless we decide to rip them out!!!!

Quote:

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Originally Posted by Greg Spencer

Ah.. I'd not realised that: great news! I wonder if we could pay the same rate on replacing our consumer units if we wrote it up as part of "rewiring associated with providing heating" :)

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Yes Greg, I think that if all work is lumped together and associated with the A/c installation then the VAT comes in @ 5%....but please confirm this independantly.

Hi, Greg Spencer :)

Welcome to RE forums...

Quote:

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Originally Posted by Greg Spencer

Ok... 10 years to raise....

Our savings on electricity.... - net gain... we'd be greener, we'd have draughts instead of all or nothing radiant heat, we'd have air-con where we had none... but the finances would not be hugely affected!

I'm still up for it... but the savings suddenly start looking less impressive given that maintenance of radiant heaters seem to amount to just about nothing and seeing as they appear destined to live forever!!!!

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....big savings and nice accommodation cannot walk hand by hand.....;)

....maybe to forget savings and just enjoy in life:) nothing last forever...

Best regards, Josip :)