Oil Aga - internal boiler choice & replacement

[simonl]

My mother's Aga has packed up after a mere 50 yrs continuous service. The boiler has failed. It's a curved copper lump held onto the side of the cast iron barrel. I have found several potential replacements, but seemingly none is made from copper. They are either steel/cast with no lining so only good for indirect systems with Furnox, or they are cast in 2 parts with a vitreous enamel coating inside. The existing setup has potable hot water passing through the Aga into a direct cylinder. No indirect bits.
Aga are quoting many weeks lead time so I'm thinking about getting one made up. Clearly copper will have the best heat transfer properties, but it'll be expensive for materials & harder to find someone with a TIG welder & the experience. The old boiler is approx 5mm thick copper plate! The outer half of the tank is in perfect order inside & out. The inside of the inner section is very badly corroded.
Here are my current questions. If anyone can answer any of them it'd be much appreciated.

1. What size is my existing copper boiler? Ideally in kW
2. When I took the boiler off it was held off from good contact with the barrel. Does it need rope behind it? Why? Does that lose heat? Does it save the boiler a bit?
3. Can I use stainless? How much worse for heat transfer?
4. Cast vitreous enamel vs copper? How much worse than existing copper tank for heat transfer.
5. Can anyone recommend a fabricator to work with copper?

Many thanks.

 

[levigsp]

A word of warning, please do not fit an aga.
I had an Aga fitted, it was fitted and serviced at 6 months by our local aga engineer [300mile]. 13 months in and it was going out every couple of days, Aga were contacted and this was there response, " you are meant to have it serviced by our engineers every 6 months, as you haven't done that an engineer would need to come out and check the aga for safety at a cost of £560 plus Vat then because of where you are the service will be £400+vat," My response if I am already paying extra for the call out for safety inspection, why am I paying again for the service?
" oh its not the same engineer who does both" my next question was, why do I need a service for the Aga every six months when it only runs a total of 8 months a year, and the last aga was in place for 50 years with a service about every three years? Answer "Our policy has changed" So a little over a year after it was fitted, it cost £1000 to get it working correctly, as I could find no independent engineer to work on an aga.
I had it serviced 6 months later and 5 month later it went out, I phoned and complained so they said they would send another engineer, but I would need to wait 1 month for a slot, "why" because your so far and you wont be paying for him to visit" . I bought new wicks fire valves etc of ebay and I do the bloody thing myself!!! but its going and being replaced with something reliable.

 

[simonl]

It's run pretty well for 50 years. I suspect anything new will be of lesser quality, hence my desire to keep it going. I certainly won't be using a blood sucking national firm to keep it going, that's for sure.

 

[windygun]

I’m no Aga expert and only work on them when I have to, normally after gas testing or working on another oil appliance in the same property. They are a total pain! To answer a couple of your queries, power output will be 10-17000 btu or 3-5 kw approx as they only heat the domestic hot water and 1 small heat leak radiator to prevent overheating. The gap between the heat exchanger and the combustion chamber will be to prevent condensation and subsequent corrosion between the 2 surfaces. Would it not be more cost effective to buy an off the shelf Aga heat exchanger and install an indirect cylinder and feed/expansion tank in the loft? The existing cylinder will probably be at the end of its life anyway.

 

[reiver]

Just be careful what you strip out/off your old Aga as they are often full of brown asbestos !!!

 

[simonl]

I’m no Aga expert and only work on them when I have to, normally after gas testing or working on another oil appliance in the same property. They are a total pain! To answer a couple of your queries, power output will be 10-17000 btu or 3-5 kw approx as they only heat the domestic hot water and 1 small heat leak radiator to prevent overheating. The gap between the heat exchanger and the combustion chamber will be to prevent condensation and subsequent corrosion between the 2 surfaces. Would it not be more cost effective to buy an off the shelf Aga heat exchanger and install an indirect cylinder and feed/expansion tank in the loft? The existing cylinder will probably be at the end of its life anyway.

Thanks for the response. It's a new tank in the loft. I Did some calcs to get power output - taking a nominal 6cc/min equates to 3.5kW of energy within the fuel for that flow rate. From that 3.5kW there's apparently 1.3kW going into the water. I've no idea how much of the remainder goes up the chimney. You mention condensation between the barrel & the boiler tank - are you only referring to when it gets switched off?

 

[Woodenbeam]

Just for balance - we have an oil fired Aga & wouldn’t be without. Can’t argue with comments regarding their service arrangements though - shocking & a pile of shite. Defo need a local guy who is reliable & able to do the job well - there is a bit of black magic to it but nothing too onerous.

That said our Aga is purely for cooking/heat source in the kitchen - no hot water involvement at all. The heating and hot water box was ticked with an external boiler.

 

[blaven]

AGA servicing was always pricey, but we had no complaints as the engineer is excellent. Latterly, however the pricing has become unreasonably high. I’m told that AGA was acquired by an American consortium in 2015 for £129million.
Seems their bean counters are fleecing the owners who are perceived to be well heeled Ideal Homes types. They take no account of those whose farmhouses and cottages have always had an AGA providing comfort in the home.
We’ve had a night storage one running now for 12 years, with one set of heating elements replaced under warranty and three fans. They are not everyone’s cup of tea, but the kitchen is always warm and the excess heat warms the house.
We wouldn’t have another though, knowing that we’re at the mercy of the firm. I sense that the engineers have been told to maximise earnings, and there is a degree of dismay in the company at how the Yanks are trying to squeeze profit out of it. Let’s be fair, they’re an expensive anachronism, not very well engineered and very inefficient,- but they do add soul to your home. I’d get an ‘Everhot’ next time. Like an AGA but better

 

[Ratwhiskers]

The Aga here is in it's third house (bought new by my parents, and brought with us every time we moved). lt too has what is known as a Saddle Boiler, and so far it's not misbehaved (45 years old, so far so good)
l can't help with the boiler OP/sir, this is just a heads up for those who suffer from power loss and continual service charges (l know they're terrible).

With oil fired Aga' it's an issue with the thermostat shutting the oil flow as the power cut strikes, then as the wicks cool and oil flow increases when power (electricity) returns the Aga inflow clogs with carbon and performance falls off and the engineer must be called.

You need to have the control box set to run constantly on the high fire setting and disengage the thermostat, the Aga will then run until it naturally carbons up (this can't be helped due to impurities/moisture in the oil it's self) at between 11 - 15 months.
Aga don't like folks knowing this, as they loose money on the service agreement (which is their biggest earner) but it can be asked for and once you've learned how (should you be inclined)..... Well, l've not paid a service charge in over thirty years, the house hasn't burned down and l'm toasty and warm.
BTW, my brotherinlaw is an Aga service engineer, haven't seen him in years......

 

[muddy42]

Get an electric Everhott, not an electric aga, ive heard bad things.

Ive had no problems so far with my EH after 4 years and no annual service required. What you lose in more expensive electricity you gain form being able to turn each oven and hob off and on as you need them.

 

[Bavarianbrit]

I bought a Lohberger wood stove 14 years ago and it still works and looks like new. Love using it, no need for pip feeds or oil tanks and wood supply near us is cheap, pallets are always given away free too.
Wood heats you twice, once when cutting it & second when in the oven.
Lohberger Varioline LC70 Classic 6kw Wood Burning Cooker - £4,138.80 :

 

[takbok]

Another Aga proponent. Keep the temperature up at optimum all the time and the burner issues go away. Ours in our new house has gone for 2 years until it needed a service. Then I simply removed the burner and cleaned it out and put in new wicks - maybe an hour of my time and £10 for enough wick strip to last a lifetime.

The Rayburn in our previous house needed the burner cleaned every 6 months because we used to turn it down then only up (a few hours in advance) when cooking was required.

It's lovely to have a warm kitchen all the time, and to be able to cook at a moment's notice.

 

[blaven]

Another Aga proponent. Keep the temperature up at optimum all the time and the burner issues go away. Ours in our new house has gone for 2 years until it needed a service. Then I simply removed the burner and cleaned it out and put in new wicks - maybe an hour of my time and £10 for enough wick strip to last a lifetime.

The Rayburn in our previous house needed the burner cleaned every 6 months because we used to turn it down then only up (a few hours in advance) when cooking was required.

It's lovely to have a warm kitchen all the time, and to be able to cook at a moment's notice.

Yeah. Pizzas from freezer to table in 12 mins.

 

[blaven]

Get an electric Everhott, not an electric aga, ive heard bad things.

Ive had no problems so far with my EH after 4 years and no annual service required. What you lose in more expensive electricity you gain form being able to turn each oven and hob off and on as you need them.

The newer 13amp. plug in a wall socket AGAs are rubbish, but the night storage ones are good. If you leave them on at low setting while you’re away they keep house warm and you don’t tend to get element failure owing to cooling and heating up again, also you don’t get oven condensation probs. leading to rusting in the ovens. Also you can run them on Economy 7 or 10 (as we do). I’d still try an Everhot next time though. Problem is, you never know how good a prouduct is till you’ve lived with it.

 

[Alantoo]

snip... They are either steel/cast with no lining so only good for indirect systems with Furnox, or they are cast in 2 parts with a vitreous enamel coating inside. The existing setup has potable hot water passing through the Aga into a direct cylinder. No indirect bits.
snip...

I would have thought going for a ready made one if you can source one is the best bet money wise. Why do you discount steel/cast for a direct system? We inherited a direct system heated by an oil wick Rayburn with a steel tank when we moved in 18 years ago...the problem here is that we are on a spring and it is very Limey water so there is a bit of furring up which I had to descale once...probably due again around now.

An alternative in your case would be to remove the boiler alltogether and just use the AGA for cooking and heating and general psychological wellbeing...and have the hot tank immersion heated on economy seven over night...which is what we do in the summer when the Rayburn is off for 6 or 7 months.

Alan

 

[Alantoo]

My cousin has managed to find the address of the company that made a new back boiler for her wood burner in Stainless Steel...we sent the whole stove to them and they made, fitted and sent it back...guess you could just send the old boiler to them...or maybe they have the dimensions for classic AGAs...they have been specialising in stainless boilers since 1981 according to their Web Site.

Rayburn, Aga, Tirolia, Stanley Stainless Steel Boilers In Stock / Made To Order | Goddard Fabrication

Hope that helps...

Alan

 

[Broadarrow]

we have a natural gas Rayburn which also has the internal bolder . We had it serviced last year by an approved Aga Rayburn service agent who made a complete and utter balls up of the whole service to a point where he caused damage to the Rayburn itself. We had to use this agnate as the local AGA dealer will not service any appliances they have not sold and installed !.
We ended up contacting AGA and making a complaint. They sent out another agent from further afield who carried out an inspection and then following their report they undertook a full service and repairs were was paid for AGA.
Great service from AGA/RAYBURN and thumbs odeon for the buffoon who buggered up our Rayburn in the first place.

When we move house the Rayburn will stay put as its getting old now. We will be considering an ESSE multi fuel cooker sd they get very good reviews and are slightly cheaper than Aga and are handmade.