Hi All,

A flat that I've been looking at with a view to purchasing is heated by an
old hot air blower system. I'm not familiar with these systems but they
don't strike me as very efficient are they straight forward to replace or
are there likely to be some lurking issues (I appreciate that it will
obviously depend on the actual system but in principle might there be some
problems)?

Cheers

Endulini wrote:
Hi All,

A flat that I've been looking at with a view to purchasing is heated by
an old hot air blower system. I'm not familiar with these systems but
they don't strike me as very efficient are they straight forward to
replace or are there likely to be some lurking issues (I appreciate that
it will obviously depend on the actual system but in principle might
there be some problems)?

Cheers
they are in fact very efficient. But if run on leccy, not necessarily cheap.

Or are these hot water fan blown convectors?

In message , The Natural Philosopher
writes
Endulini wrote:
Hi All,
A flat that I've been looking at with a view to purchasing is heated
by an old hot air blower system. I'm not familiar with these systems
but they don't strike me as very efficient are they straight forward
to replace or are there likely to be some lurking issues (I
appreciate that it will obviously depend on the actual system but in
principle might there be some problems)?
Cheers
they are in fact very efficient. But if run on leccy, not necessarily cheap.

Or are these hot water fan blown convectors?

I presume its a Johnson & Starley gas system

It'll be a complete rip it out and start from scratch job

--
geoff

On May 30, 12:49*am, The Natural Philosopher
wrote:
Endulini wrote:
Hi All,

A flat that I've been looking at with a view to purchasing is heated by
an old hot air blower system. I'm not familiar with these systems but
they don't strike me as very efficient are they straight forward to
replace or are there likely to be some lurking issues (I appreciate that
it will obviously *depend on the actual system but in principle might
there be some problems)?

Cheers

they are in fact very efficient. But if run on leccy, not necessarily cheap.

Or are these hot water fan blown convectors?

All electric heating is 100% efficient by default. If it's gas it may
well be in poor or even dangerous condition. The heat exchangers can
perforate allowing combustion products into the rooms.
Best got rid of.

However, before dashing to gas consider heat pumps. There is to be a
government initiative subsidising their installation and running cost
for 20 years. (Tax free)
Google Renewable Heat Incentive. Not sure of the exact position at
the moment but ones installed now will qualify I believe, the scheme
is to start next year.

In message , Endulini
writes
Hi All,

A flat that I've been looking at with a view to purchasing is heated by
an old hot air blower system. I'm not familiar with these systems but
they don't strike me as very efficient are they straight forward to
replace or are there likely to be some lurking issues (I appreciate
that it will obviously depend on the actual system but in principle
might there be some problems)?

'60's build?

Off peak electric, *concrete block*, ducted air. My wife has inherited a
flat which originally had such a system.

There were two main problems. The heater elements age and need
replacement. The system is probably undersized for maintaining comfort
levels by late evening which encourages occupants, particularly tenants,
to minimise ventilation leading to condensation on cold outside walls.

Flat ownership is a bit of a minefield in that what you can do to the
outside walls may depend on others. Cavity wall insulation operators
would not look at ours, there was a great to do over fitting plastic
double glazing, gas fired wet heating was initially resisted although
most have now been converted.

The gas fitter who installed our system said he had found asbestos
insulation but I did not see any evidence and there was no disposal
charge.

You could look at other flats in the block and see what other owners
have done. Gas flues, double glazing etc. There will be a *management
organisation* who will have final say on such matters.

regards

--
Tim Lamb

On May 30, 12:42*am, "Endulini" wrote:
Hi All,

A flat that I've been looking at with a view to purchasing is heated by an
old hot air blower system. I'm not familiar with these systems but they
don't strike me as very efficient are they straight forward to replace or
are there likely to be some lurking issues (I appreciate that it will
obviously *depend on the actual system but in principle might there be some
problems)?

Cheers

Cue resident loony extolliing their praises.

cynic wrote:
On May 30, 12:42 am, "Endulini" wrote:
Hi All,

A flat that I've been looking at with a view to purchasing is heated by an
old hot air blower system. I'm not familiar with these systems but they
don't strike me as very efficient are they straight forward to replace or
are there likely to be some lurking issues (I appreciate that it will
obviously depend on the actual system but in principle might there be some
problems)?

Cheers

Cue resident loony extolliing their praises.

Hot air systems are very very good at getting a space up to temperature
quickly with very few hot spots.

They also are compact.

Their efficiency and cost depends on how they are driven..

cynic wrote:

On May 30, 12:42 am, "Endulini" wrote:
Hi All,

A flat that I've been looking at with a view to purchasing is heated by an
old hot air blower system. I'm not familiar with these systems but they
don't strike me as very efficient are they straight forward to replace or
are there likely to be some lurking issues (I appreciate that it will
obviously depend on the actual system but in principle might there be some
problems)?

Cheers

Cue resident loony extolliing their praises.

My heavens, but you have the gift of prophecy!

On Mon, 30 May 2011 10:20:59 +0100, The Natural Philosopher
wrote:


Cue resident loony extolliing their praises.

Hot air systems are very very good at getting a space up to temperature
quickly with very few hot spots.


We had a Johnson & Starley gas system. It did indeed heat the room air
very quickly. Unfortunately all the furnishings and fittings etc
stayed cold to the touch for just as long a time as a wet CH system.

They also are compact.

Absolutely untrue of the "Electricaire" systems.


Their efficiency and cost depends on how they are driven.

The joints in the ductwork in our system were sealed with ("Waddya
Know!) duct tape which dried out, went crispy and dropped off, leading
to loss of hot air.

It also blew dust about the house and the main circulating fan was
unbalanced, hence noisy, from day one.

Derek G

On Mon, 30 May 2011 10:20:59 +0100, The Natural Philosopher
wrote:

Hot air systems are very very good at getting a space up to temperature
quickly with very few hot spots.

The one we had in Scotland certainly did that. When it came on the
cat was flung across the room and left clinging to the curtains.
Conversation became impossible and TV could only be understood by lip
readers.

They also are compact.

I'm not sure the 8ft x 4ft x 4ft container of bricks heated by
electric elements which filled what would otherwise have been a useful
storeroom by the front door could by any stretch of the imagination be
called "compact".

Their efficiency and cost depends on how they are driven..

The room the bricks were in was very warm, very useful for helping
epoxy glue to harden. Unfortunately the heat loss during the day
(when no one was in) was such that by the evening nothing much
remained. Fortunately the design was so bad that the large contactor
used to change from peak to off peak had fused shut into the off peak
mode.

In message , Derek G.
writes
On Mon, 30 May 2011 10:20:59 +0100, The Natural Philosopher
wrote:


Cue resident loony extolliing their praises.

Ssh ...

resident loony's been quite for a while


Hot air systems are very very good at getting a space up to temperature
quickly with very few hot spots.


We had a Johnson & Starley gas system. It did indeed heat the room air
very quickly. Unfortunately all the furnishings and fittings etc
stayed cold to the touch for just as long a time as a wet CH system.

They also are compact.

Absolutely untrue of the "Electricaire" systems.


Their efficiency and cost depends on how they are driven.

The joints in the ductwork in our system were sealed with ("Waddya
Know!) duct tape which dried out, went crispy and dropped off, leading
to loss of hot air.

It also blew dust about the house and the main circulating fan was
unbalanced, hence noisy, from day one.


Although modern J&S systems have an electrostatic dust collection system

As for the fan - you should have rejected it if it was new - the
additional problem is resonance in all that metalwork

Not sure I'd want one


--
geoff

Derek G. wrote:
On Mon, 30 May 2011 10:20:59 +0100, The Natural Philosopher
wrote:


Cue resident loony extolliing their praises.
Hot air systems are very very good at getting a space up to temperature
quickly with very few hot spots.


We had a Johnson & Starley gas system. It did indeed heat the room air
very quickly. Unfortunately all the furnishings and fittings etc
stayed cold to the touch for just as long a time as a wet CH system.

They also are compact.

Absolutely untrue of the "Electricaire" systems.

Their efficiency and cost depends on how they are driven.

The joints in the ductwork in our system were sealed with ("Waddya
Know!) duct tape which dried out, went crispy and dropped off, leading
to loss of hot air.

It also blew dust about the house and the main circulating fan was
unbalanced, hence noisy, from day one.

Derek G

well don't blame a class of heating for one badly implemented system


I was merely trying to make the pit that there is nothing wrong with hot
air blowers per se. Its how they are installed and what they run off,
that makes for a good or bad system.

I've got blown convectors plumbed into the hot water circuit. Neat and
compact, just a bit noisy.

Peter Parry wrote:
On Mon, 30 May 2011 10:20:59 +0100, The Natural Philosopher
wrote:

Hot air systems are very very good at getting a space up to temperature
quickly with very few hot spots.

The one we had in Scotland certainly did that. When it came on the
cat was flung across the room and left clinging to the curtains.
Conversation became impossible and TV could only be understood by lip
readers.

They also are compact.

I'm not sure the 8ft x 4ft x 4ft container of bricks heated by
electric elements which filled what would otherwise have been a useful
storeroom by the front door could by any stretch of the imagination be
called "compact".

Their efficiency and cost depends on how they are driven..

The room the bricks were in was very warm, very useful for helping
epoxy glue to harden. Unfortunately the heat loss during the day
(when no one was in) was such that by the evening nothing much
remained. Fortunately the design was so bad that the large contactor
used to change from peak to off peak had fused shut into the off peak
mode.

Sounds fairly typical of Scotlands approach to power.

On May 30, 11:26*am, (Steve Firth) wrote:
cynic wrote:
On May 30, 12:42 am, "Endulini" wrote:
Hi All,

A flat that I've been looking at with a view to purchasing is heated by an
old hot air blower system. I'm not familiar with these systems but they
don't strike me as very efficient are they straight forward to replace or
are there likely to be some lurking issues (I appreciate that it will
obviously *depend on the actual system but in principle might there be some
problems)?

Cheers

Cue resident loony extolliing their praises.

My heavens, but you have the gift of prophecy!

To be perfectly honest that wasnt the character I anticipated.

cynic wrote:

On May 30, 11:26 am, (Steve Firth) wrote:
cynic wrote:
On May 30, 12:42 am, "Endulini" wrote:
Hi All,

A flat that I've been looking at with a view to purchasing is heated
by an old hot air blower system. I'm not familiar with these systems
but they don't strike me as very efficient are they straight forward
to replace or are there likely to be some lurking issues (I
appreciate that it will obviously depend on the actual system but
in principle might there be some problems)?

Cheers

Cue resident loony extolliing their praises.

My heavens, but you have the gift of prophecy!

To be perfectly honest that wasnt the character I anticipated.

Yebbut, still a resident loony. No doubt the other loony will be along
as soon as nursey releases the strait jacket and attaches his headstick.

On May 30, 12:42*am, "Endulini" wrote:
Hi All,

A flat that I've been looking at with a view to purchasing is heated by an
old hot air blower system. I'm not familiar with these systems but they
don't strike me as very efficient are they straight forward to replace or
are there likely to be some lurking issues (I appreciate that it will
obviously *depend on the actual system but in principle might there be some
problems)?

Cheers

You havent told us what trype of system this is yet.

If its gas fired ducted hot air, theres no reason to replace, as long
as you dont mind mild background noise when it runs. The boilers to
use in such systems are still being sold new, albeit by only one
company.

If its blower radiators on a water based system, these perform much
the same as ordinary CH, but the rads are much smaller and make a
little noise.

If its fanned storage heating, they're bulky and csot more to run than
gas or oil, and old units may not store enough heat to keep a place
warm all evening. Insulation can solve this, or replacement new
heaters are better at predicting heat needs and storing enough.


NT

On 30/05/2011 11:36, Derek G. wrote:

It also blew dust about the house and the main circulating fan was
unbalanced, hence noisy, from day one.


You didn't mention spiders. Or is that rumour not true?

Andy

On Mon, 30 May 2011 08:08:50 -0700 (PDT), Tabby
wrote:

On May 30, 12:42*am, "Endulini" wrote:
Hi All,

A flat that I've been looking at with a view to purchasing is heated by an
old hot air blower system. I'm not familiar with these systems but they
don't strike me as very efficient are they straight forward to replace or
are there likely to be some lurking issues (I appreciate that it will
obviously *depend on the actual system but in principle might there be some
problems)?

Cheers

You havent told us what trype of system this is yet.

If its gas fired ducted hot air, theres no reason to replace, as long
as you dont mind mild background noise when it runs. The boilers to
use in such systems are still being sold new, albeit by only one
company.

If its blower radiators on a water based system, these perform much
the same as ordinary CH, but the rads are much smaller and make a
little noise.

If its fanned storage heating, they're bulky and csot more to run than
gas or oil, and old units may not store enough heat to keep a place
warm all evening. Insulation can solve this, or replacement new
heaters are better at predicting heat needs and storing enough.


NT


I bought a new house in 1970 that had a warm air CH system, originally
oil-fired, from a central distibution storage tank. There was no gas
in the small town at the time. The downstairs ducts were all under the
suspended floor. When town gas was supplied about 10 years later,
most of my neighbours changed over to gas-fired boilers, and many also
changed to radiators. I eventually bought a new gas-fired warm air
boiler and retained the ducts. I found that they were perfectly
effective - although I realised later that the original design was
technically flawed.

If you study a/c systems in hotel rooms, you will see both inlet and
outlet ducts for good circulation. Our builder had installed only
inlet ducts - assuming that the return air would find a way back via
gaps around the doors. Bad design that, just to keep the costs down.

David

On May 30, 9:58*pm, David J wrote:
On Mon, 30 May 2011 08:08:50 -0700 (PDT), Tabby
wrote:



On May 30, 12:42*am, "Endulini" wrote:
Hi All,

A flat that I've been looking at with a view to purchasing is heated by an
old hot air blower system. I'm not familiar with these systems but they
don't strike me as very efficient are they straight forward to replace or
are there likely to be some lurking issues (I appreciate that it will
obviously *depend on the actual system but in principle might there be some
problems)?

Cheers

You havent told us what trype of system this is yet.

If its gas fired ducted hot air, theres no reason to replace, as long
as you dont mind mild background noise when it runs. The boilers to
use in such systems are still being sold new, albeit by only one
company.

If its blower radiators on a water based system, these perform much
the same as ordinary CH, but the rads are much smaller and make a
little noise.

If its fanned storage heating, they're bulky and csot more to run than
gas or oil, and old units may not store enough heat to keep a place
warm all evening. Insulation can solve this, or replacement new
heaters are better at predicting heat needs and storing enough.

NT

I bought a new house in 1970 that had a warm air CH system, originally
oil-fired, from a central distibution storage tank. There was no gas
in the small town at the time. The downstairs ducts were all under the
suspended floor. *When town gas was supplied about 10 years later,
most of my neighbours changed over to gas-fired boilers, and many also
changed to radiators. I eventually bought a new gas-fired warm air
boiler and retained the ducts. I found that they were perfectly
effective - although I realised later that the original design was
technically flawed.

If you study a/c systems in hotel rooms, you will see both inlet and
outlet ducts for good circulation. Our builder had installed only
inlet ducts - assuming that the return air would find a way back via
gaps around the doors. *Bad design that, just to keep the costs down.

David *

Easily solvable though, with louvre style grills in doors


NT

On Mon, 30 May 2011 10:20:59 +0100, The Natural Philosopher wrote:

Hot air systems are very very good at getting a space up to temperature
quickly with very few hot spots.

But unless all the rooms are conveniently arranged directly around the WA
unit there may be permanently cold spots. Some otherwise very nice 60s
Modern flats round here have the unheated bathrooms because they don't
adjoin the WA units!

They also are compact.

Er, eh?! A full-size cupboard devoted to the WA unit and ducting compared
to a suitcase-sized gas boiler? Plus a HW cylinder and storage tank
because you don't get 'combi' WA units.

Their efficiency and cost depends on how they are driven..

The gas-fired units I've seen have permanent pilot lights on both the
main WA unit and the separate water heater part, hence dinosaur levels of
efficiency. I'd guess newer models might get up to standard efficiency.
Do they even make high-efficiency (condensing) models?

--
John Stumbles -- http://yaph.co.uk

It's bad luck to be superstitious.

On Mon, 30 May 2011 19:13:09 +0100, Andy Champ
wrote:

On 30/05/2011 11:36, Derek G. wrote:

It also blew dust about the house and the main circulating fan was
unbalanced, hence noisy, from day one.


You didn't mention spiders. Or is that rumour not true?


The fan only runs in the heating season.

We did gcome across the occasional crispy specimen dessicated by the
hot air at 75C.

Derek G

On May 30, 11:01*pm, Tabby wrote:
On May 30, 9:58*pm, David J wrote:





On Mon, 30 May 2011 08:08:50 -0700 (PDT), Tabby
wrote:

On May 30, 12:42*am, "Endulini" wrote:
Hi All,

A flat that I've been looking at with a view to purchasing is heated by an
old hot air blower system. I'm not familiar with these systems but they
don't strike me as very efficient are they straight forward to replace or
are there likely to be some lurking issues (I appreciate that it will
obviously *depend on the actual system but in principle might there be some
problems)?

Cheers

You havent told us what trype of system this is yet.

If its gas fired ducted hot air, theres no reason to replace, as long
as you dont mind mild background noise when it runs. The boilers to
use in such systems are still being sold new, albeit by only one
company.

If its blower radiators on a water based system, these perform much
the same as ordinary CH, but the rads are much smaller and make a
little noise.

If its fanned storage heating, they're bulky and csot more to run than
gas or oil, and old units may not store enough heat to keep a place
warm all evening. Insulation can solve this, or replacement new
heaters are better at predicting heat needs and storing enough.

NT

I bought a new house in 1970 that had a warm air CH system, originally
oil-fired, from a central distibution storage tank. There was no gas
in the small town at the time. The downstairs ducts were all under the
suspended floor. *When town gas was supplied about 10 years later,
most of my neighbours changed over to gas-fired boilers, and many also
changed to radiators. I eventually bought a new gas-fired warm air
boiler and retained the ducts. I found that they were perfectly
effective - although I realised later that the original design was
technically flawed.

If you study a/c systems in hotel rooms, you will see both inlet and
outlet ducts for good circulation. Our builder had installed only
inlet ducts - assuming that the return air would find a way back via
gaps around the doors. *Bad design that, just to keep the costs down.

David *

Easily solvable though, with louvre style grills in doors

NT- Hide quoted text -

- Show quoted text -

Not good in a fire that idea.

On Mon, 30 May 2011 21:58:12 +0100, David J
wrote:


I bought a new house in 1970 that had a warm air CH system, originally
oil-fired, from a central distibution storage tank. There was no gas
in the small town at the time. The downstairs ducts were all under the
suspended floor. When town gas was supplied about 10 years later,
most of my neighbours changed over to gas-fired boilers, and many also
changed to radiators. I eventually bought a new gas-fired warm air
boiler and retained the ducts. I found that they were perfectly
effective - although I realised later that the original design was
technically flawed.

If you study a/c systems in hotel rooms, you will see both inlet and
outlet ducts for good circulation. Our builder had installed only
inlet ducts - assuming that the return air would find a way back via
gaps around the doors. Bad design that, just to keep the costs down.


Our 1972 Wimpey house (so presumably centrally specified) had flow and
return vents (The *big* return vent) in the through lounge, but all
the rooms upstairs had a couple of inches removed from the lights over
the upstairs doors to create an unimpeded path back to the big vent in
the lounge. It had no adverse aspects.

Derek G

In article ,
harry writes:
On May 30, 12:49*am, The Natural Philosopher
wrote:
Endulini wrote:
Hi All,

A flat that I've been looking at with a view to purchasing is heated by
an old hot air blower system. I'm not familiar with these systems but
they don't strike me as very efficient are they straight forward to
replace or are there likely to be some lurking issues (I appreciate that
it will obviously *depend on the actual system but in principle might
there be some problems)?

Cheers

they are in fact very efficient. But if run on leccy, not necessarily cheap.

Or are these hot water fan blown convectors?
All electric heating is 100% efficient by default.

Since it is struggling to reach even 40% efficient when it
gets to you, that would be difficult. That's partly why it's
more expensive than gas.

If it's gas it may
well be in poor or even dangerous condition. The heat exchangers can
perforate allowing combustion products into the rooms.
Best got rid of.

I rented a house with a J&S warm air system many years ago, and I
quite liked it. Very quick warm up from a standing start. However,
it would be a disaster if anyone smokes, and it caused dryness
which one of the other occupiers claimed caused problems with
contact lenses.

I believe they do drop-in modern replacements for older systems,
if you do consider keeping the infrastructure.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

Hint: Electric storage heaters & panel heaters work fine for flats -
once you have 50mm Celotex on the walls.

I would fix the insulation first.

Oil really is likely to be 300$/barrel by 2020 which basically means
the average heating bill will be £2800-3700.

"Derek G." wrote in message
...
On Mon, 30 May 2011 21:58:12 +0100, David J
wrote:


I bought a new house in 1970 that had a warm air CH system, originally
oil-fired, from a central distibution storage tank. There was no gas
in the small town at the time. The downstairs ducts were all under the
suspended floor. When town gas was supplied about 10 years later,
most of my neighbours changed over to gas-fired boilers, and many also
changed to radiators. I eventually bought a new gas-fired warm air
boiler and retained the ducts. I found that they were perfectly
effective - although I realised later that the original design was
technically flawed.

If you study a/c systems in hotel rooms, you will see both inlet and
outlet ducts for good circulation. Our builder had installed only
inlet ducts - assuming that the return air would find a way back via
gaps around the doors. Bad design that, just to keep the costs down.


Our 1972 Wimpey house (so presumably centrally specified) had flow and
return vents (The *big* return vent) in the through lounge, but all
the rooms upstairs had a couple of inches removed from the lights over
the upstairs doors to create an unimpeded path back to the big vent in
the lounge. It had no adverse aspects.

Derek G
Cheers everyone that answered. Have offered on a different flat for a number
of unrelated reasons, however grateful for the advice all the same. And
sorry for releasing the resident looney

"Endulini" wrote in message
om...

Hi All,

A flat that I've been looking at with a view to purchasing is heated by an
old hot air blower system. I'm not familiar with these systems but they
don't strike me as very efficient are they straight forward to replace or
are there likely to be some lurking issues (I appreciate that it will
obviously depend on the actual system but in principle might there be some
problems)?



Some warm air heating systems, especially but not only pre 1980s system I
believe, may contain asbestos in the ducting.

I would recommend for £100 to £200 asking for an asbestos survey of the
system before you touch the ducting.

Other than that I wouldn't let the warm air system put you off and I
wouldn't necessarily replace it in terms of efficiency unless you really
don't like it. It's also possible to replace older boilers with more
efficient and modern warm air boilers.

--
* I promise I will format my posts properly in the future.
* Windows Live Mail just can't quote! Luckily, I have found this:
* http://www.dusko-lolic.from.hr/wlmquote/