Warm Air Heating Systems - Do you have any experience with them?

matt.j_3

Hi All,

We are hoping to move house soon and have made an offer on a property. 

We have had the seller report come back from our solicitors today and it says that the central heating system is a Warm Air Heating System. I have never heard of these so I have done some basic research to understand what they are. 

The system has been well maintained and is on a service plan according to the information provided by our solicitors. The last service report (done a month ago) says that despite it being 15 years old it is in very good condition.

Has anyone had any experience with Warm Air Heating Systems? Are they costly to run, are the efficient for heating etc, are there any issues with them in general (other than keeping the vents dust free)?

Tallerdave

I lived in a flat with one once and would describe it as noisy and crap. Lukewarm puffing one minute, freezing the next.

You should budget to replace it with gas central heating including the cost of blocking off/removing all the vents.

Gerry1

Which fuel does it use?

matt.j_3

Gerry1 said:

Which fuel does it use?

I believe it is gas

Reed_Richards

Warm air heating is extremely common in North America and rarely seen in the UK.  Over there you would have a "furnace" in the basement so the warm air only has to go up, which it does naturally.  In summer you may be able to switch over to cool air for air conditioning; I don't really know how that works.

The way you heat the air is the most important factor for running costs so make absolutely sure you know how it works.    

macman

Am I the only person who is incredulous that you have viewed a property, made an offer on it, and started to spend money on conveyancing, without the slightest idea of how the property is heated and hot watered? And even now you are not entirely sure if it is gas, oil, LPG or electric? 
As others has intimated, hot-air heating was briefly fashionable back in the 1970's, mainly as an American import. It is effectively obsolete now, and spares and service will be expensive, if available at all. The actual running costs will be little different than the wet CH equivalent: i.e if it's gas powered, it will be similar to a gas boiler driving wet CH. If it's electric, the costs will be 300-400% more..
You need to budget for a complete new mains gas CH system and rads, plus removal of the air vent system, which will probably be upwards of £4K, depending on system size.

matt.j_3

macman said:

Am I the only person who is incredulous that you have viewed a property, made an offer on it, and started to spend money on conveyancing, without the slightest idea of how the property is heated and hot watered? And even now you are not entirely sure if it is gas, oil, LPG or electric? 
As others has intimated, hot-air heating was briefly fashionable back in the 1970's, mainly as an American import. It is effectively obsolete now, and spares and service will be expensive, if available at all. The actual running costs will be little different than the wet CH equivalent: i.e if it's gas powered, it will be similar to a gas boiler driving wet CH. If it's electric, the costs will be 300-400% more..
You need to budget for a complete new mains gas CH system and rads, plus removal of the air vent system, which will probably be upwards of £4K, depending on system size.

I am sorry you are feeling incredulous.

But, to put your mind to rest we have only made an offer and received back the initial sellers info pack. We love the house for size, perceived condition (before homebuyers survey), internal rooms and space, the house location, local schooling performance, price, amenities etc, so made an offer on it.

We have not conducted a full homebuyers survey yet as we needed further formal information that wasn't provided by the estate agent, therefore we have start a limited activity with our solicitor to collect the information the estate agent is unable to provide. 

Now the heating system is known to us we can do some research to be able to ask better questions of the current owners instead of guessing, that way it can form part of our decision to proceed (with the knowledge we may need to invest in a new heating system at a later date), get a formal survey done etc, or withdraw entirely before we spend money of the process. 

I hope that make feel a bit less incredulous, but thank you for your concern.

Reed_Richards

In principle an air-to-air heat pump would be a very efficient way of warming the air if your prospective house does not have gas.  But whether you could find a suitably sized unit and someone to fit it for you is a moot point.

macman

Yes, of course you can withdraw or amend your offer at any time. But I am surprised that knowing whether the heating cost might be £1,000 a year or £3,000 a year would not be part of your consideration in making your initial offer. Houses with mains gas wet CH are invariably sold at a premium over those without: where mains gas is available, those without it will prove much less attractive to most buyers, unless they are buying it to gut it anyway.
I appreciate that not everyone takes a practical approach, but the lack of radiators would have been a fairly obvious indication when viewing. And the EPC should describe the power source for the heating (eg, mains gas), although it probably won't specify it as a hot-air system.

matelodave

I've had a house with one and so has my Mum. Our had a fan to circulate the air, my Mum's just relied on convection. However you'd have to know how the one you are contemplating operates and is controlled.

Ours had a thermostat in the lounge which controled the gas valve and the blower would only come on when the plenum was hot so it didn't blow cold air (unless you specifically wanted it to, like in the summer). warm air would come out of the lower vents.

Mum's just had a thermostat inside the unit which controlled the gas valve in sympathy with the temperature of the air that wafted in through the lower vents. Warm air was convected past the heat exchanger and came out of the top.

In both places there were high level vents above the doors to help air circulation around the house and the unit was mounted centrally with vents into the rooms that required heating. Neither had ducting to heat upstairs, it just relied on warm air fighting out of the high level vents and getting upstairs so we both needed supplementart heating in the bedrooms.

They are reasonably effective at keeping the place warm but even though they have filters (which have to be cleaned regularly) they do cause a lot of dust.

I cant remember how much they cost to run, we left our place place in 1978 and my Mum had hers around 20 years ago and sorted her own bills out.

You'll also need to see how the hot water is heated - ours had a gas power hot water "circulator" (a bit like an Ascot for those who can remember them) which was controlled by a thermostat on the tank and heated water which circulated through the heating coils on the hot tank. My Mum's place just had a normal electric immersion heater for hot water.

TBH I thought they were OK and my Mum was quite happy with hers but if i were you I'd be looking at removing the unit and getting it replaced with a proper hot water gas system.

You'll gain the space where the unit was (be prepared for some building works to sort it all out though and work out where you'd put the boiler, rads and hot water tank.

st999

I used to have Johnson and Starley gas fired warm air heating and it kept the house warm enough.

I never had problems with dust and the fan was only noisy when the heating came on when the house was cold.

 However I had a BG maintenance contract and every year it was serviced, BG was the only company that would service it in my area, the engineer kept finding fault with the ventilation, one year keep door closed, the next remove door etc.

The final straw was when I had to knock a hole in an exterior wall as the floor ventilation was considered in efficient.

This caused an almighty draught in the kitchen every time the heating came on and my gas usage started to increase from the previous year.
Also the maintenence contract price was increased.

I had the heating system replaced with a combi and radiators and my gas usage decreased from 23,000 to 18,000 approx per year to 14,500 kWh per year and my kitchen was considerably draught free.

I am therefore saving anyting up to 8,500 kWh of gas and the £300 a year Bg want to maintain it.

I now use a local heating company to service it once a year though I am still waiting to get it serviced this year, for conciderly less that BG want.