Johnson & Starley warm air units

[fred]

Does anyone have experience of this type of central heating? Good/bad/efficency/economy etc etc Any input much appreciated TIA

[Dave Plowman (News)]

Think it very much depends on the age of the unit - and how well the installation was done.

[laughing-at-phil]

It's a fairly new unit, replaced within the last 5 years, in a house we might purchase (designed around this type of system). The neighbour thinks it's great, but a friend of mine thinks warm air heating is ****** ****** or worse.

[fred]

Excuse the change of nick

[Dave Plowman (News)]

It generally has a poor reputation in this country due to poor design and installation which is where you're mate's views probably come from. But if your neighbour is happy could be 'yours' is one of the better ones. Could you check with other neighbours too?

[<me9]

I had one once. (well twice but the other one was identical apart from the name) It worked fine, fast warmup, full output could be diverted to one room (bathroom in morning) for extra quick warmup.

The second one was replaced after I extended my present house, it was inefficient with extra ducting to heat up on each burn. I replaced with radiators 15 years ago and haven't looked back.

Pros

Fast warmup .

Economical in a simple system.

good ventilation, reduced condensation.

Cons

less controllable than a wet system (only one zone).

Uneconomical with long ducting to some rooms.

needed return air path, circulating smells, pollen etc.

Temperature fluctuations.

[GMM]

Well, I have an old version of this - probably getting on for 40 years old - and it's not great. I'm currently thinking about putting in a wet system before it finally gives up the ghost. Apart from the inefficiency of my old system, I would say the problems are incomplete coverage (ie if it's not well designed, it isn't as easy to modify as a wet system), poor control (opening and shutting vents isn't as simple as setting a TRV and leaving it, plus the thermostat seems to have a mind of its own, although that could just be my one), sound transmission around the house through the ducting, inflexibility when it comes to furniture positions (if radiators get in the way here, remember that you need a clear path from the vent into the room) and an overly dry dusty atmosphere. In terms of capital cost, should the main unit fail, you can install an entire wet system for less than a direct boiler replacement.

The positives are a fast warm up (but an equally fast cool down) and the ability to circulate unheated air when the weather is very warm (should that ever occur again this summer!). I am toying with the idea of changing to a wet system, but keeping the vents and installing a decent fan for a sort of pseudo air con system, although I haven't found a suitable fan yet....

I hope that helps. In the end, I should think it's neither as bad or as good as some people would tell you. One thing's certain though - nobody wants to buy your house once they notice it, and that's what will drive my change.

[GMM]

=A0 London SW

[fred]

Thanks folks, yes, i'm quite prepared to have a wet system installed if necessary. The house we might purchase is actually a bungalow so i'd expect the pipework would be very obtrusive, sadly.

[Andrew Gabriel]

I rented a house with one -- the whole estate had been built with them in every house. Don't recall what make it was though.

I quite liked it -- the fast warm up was great if you don't have predictable occupancy times which suite a timeswitch.

Others in the house didn't like it -- got problems with the dryness it caused making peoples' throats dry and irritating contact lenses. None of us smoked, but that would have been a complete disaster. Only rooms abutting the central air plenum got heating, so the bathroom and third bedroom didn't. It's well beyond the average householder to work out how to balance the register plates so all the hot air doesn't just go into one room (just like you wouldn't expect them to be able to balance a radiator system, but they are expected to be able to balance a warm air system). Even just opening or closing doors can have a dramatic effect. We were one of the very few houses on the estate which hadn't had the system replaced with radiators, and they weren't old enough to have worn out, so that's probably the best indication you can get of what most people thought of them.