Heat flow metering

[YAPH]

Anyone know of any off-the-shelf heat metering systems? I'm looking at an application in a house converted into flats with a shared boilers + hot water system, as an alternative to one combi for each flat and separate gas meters. Obviously one could home-brew it and I've seen something like this with Kent water meters with an add-on digital reader, plus temperature sensors strapped on to flow and return pipes. I'll see if I can find a lead on this system, but wondered if our clued-up friends here knew of other, ready-rolled and reasonably priced (FSVO "reasonable" :-)) systems out there in the wild.

[andrew]

http://195.49.61.77/landisgyr/landisgyr/Europe/_www/en/pub/productssolutions/heatandcold/ultraheat_2wr5_der_hochpraes.htmAre the ones fitted to a biomass boiler I service, I log the date time and reading each visit and try to relate this to woodchip deliveries but no one else seems interested.

Apparently the same sort of thing is fitted in the landlord's cupboard of a social housing biomass powered flats in Brixton, one for each of 12 flat but they've lost the key so I've never had a look in. AFAIK they've never been accepted by the tenants so I don't know who foots the heating bill.

I'd be interested in how much they cost.

AJH

[Dave Liquorice]

A similar thought went through my mind having read the OP. I would definately not be happy being billed by a home brew energy metering system. I'd not be overly happy about a commercial meter either but could be persuaded provided evidence of it's calibration could be provided.

There may be things in the letting regulations that mean that "proper" meters have to be used anyway.

[Andy Wade]

Danfoss comes to mind (district heating being a Big Thing in Denmark):

[Bill Wright]

heating scheme. It was abandoned, one reason being that many meters registered unfeasibly low room temperatures. Each main room had a thing on the wall that looked like a normal thermostat. The tenants learnt to keep a plastic bag full of ice hanging on the wall just above the 'thing'. In one case I witnesses the use of an ancient packet of peas for this purpose.

Bill

[YAPH]

http://195.49.61.77/landisgyr/landisgyr/Europe/_www/en/pub/productssolutions/heatandcold/ultraheat_2wr5_der_hochpraes.htmThanks for the link.

I think I'd be rather scared to know ;-)

[YAPH]

("Sounds like Mexican food. Don't tell them I said that") in Southampton. Andy at Tacanova priced me 22mm Sonometers with necessary fittings at about £450 inc. They also do Aqualux units comprising one or two PHEs and a metering unit plus flow-switches, valves etc necessary to make a module that sits on a heat main and supplies metered CH and DHW to a consumer (house, flat etc). These work out around 1250 (one PHE) to 1600 (2 PHEs) which is probably peanuts for their intended market but is slightly eye-watering for my prospective customer.

The Sonometer units can have various interfaces to enable integration into BMSes or remote reading etc, and to this end have pulse inputs so you can connect (suitable) water & leccy meters into them and have one device that relays all metering info to wherever.

In my application the units would be standalone and A Little Man would come along and read them from time to time. They store metering data (in EEPROM) for a given period, depending on how frequently you configure it to sample - intervals of anything from a few minutes to a day IIRC.

[John Rumm]

Sounds like something that ought to be easy enough to cobble together if one could get a reasonably accurate flow rate[1] indication. Combined with a bit of differential temperature sensing, you could computer heat transfer. Validation against the total energy bill would give a good indication of accuracy (which would not need to be precise - just good enough to establish the ratio of split between the various users).

[1] a flap valve acting against a spring in the flow would probably do it. Sensing the valve position using either a magnet and hall effect device or a LDR and light source with a moving blind positioned between them.

[YAPH]

To answer my own question (for the sake of googlers coming later) I've just found that BES do one. Page 97 of the current (Sept 2009) catalogue, p/n 17955 for the meter itself at £173.25 ex VAT, to which you must add a separate flow meter such as p/n 13771 (3/4", for hot) at £44.42 ex VAT.

[newshound]

Never seen it here, but I visited someone in Holland in the 1970's in "retirement flats" where they had little open ended vertical tubes of volatile oil near the radiators. The tenants were billed according to the fall in level of these sensors.