Smiths heater replacement

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Stevie R
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Smiths heater replacement

Post by Stevie R »

My Moggy has the smiths circular heater it’s a bit tired and could probably do with replacing, not had much experience in this field and I was wondering if there is an alternative that I can replace it with without too much of a faff
philthehill
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Re: Smiths heater replacement

Post by philthehill »

A common heater conversion is to fit the Classic Mini fresh air heater.
I had the Classic Mini heater fitted to my Ser 2 and it worked well.
The conversion details can be found in the Owen Burton Marina to Minor booklet 2nd edition.

firedrake1942
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Re: Smiths heater replacement

Post by firedrake1942 »

They are quite simple beasties and mine at least is very efficient.

I may be entering a teaching / sucking eggs situation but many users do not realise that turning the knob fully round actually puts the heater / blower on its lowest setting where as just clicking it on, gives the highest. It is worth running descaler through the heater and checking that the tap at the back go the engine is open to allow hot water from the. cooling system engine.

Check the switch / rheostat is clean and working, it will make a difference. They often get coated in dust and fluff.

Check that the pipes to the windscreen vents are a) not blocked and b) connected Something as simple as this can often solve a condensation issue

One issue I came across was that a Minor owner had fitted a new (deeper) parcel shelf to their 1958 car and effectively blocked the bottom air outlets from the heater. The original shallower shelf allows air from the bottom vents.
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Stevie R
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Re: Smiths heater replacement

Post by Stevie R »

Thanks for the info @firedrake1942 I’ll give what you suggested a try looking at info on some platforms it says turn the button fully clockwise and then turn it back anticlockwise approx 1/2 inch and that’s on full, another says do the opposite?
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geoberni
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Re: Smiths heater replacement

Post by geoberni »

Stevie R wrote: Tue Oct 15, 2024 9:20 am Thanks for the info @firedrake1942 I’ll give what you suggested a try looking at info on some platforms it says turn the button fully clockwise and then turn it back anticlockwise approx 1/2 inch and that’s on full, another says do the opposite?
Whether the heater is a Smiths, or an aftermarket like my Tudor, they are controlled by a Rheostat, which is basically a wire wound variable resistor on a ceramic former, a ring in the case of car heaters.
It's convention, for reasons I won't bother you with, when using such a resistive switch to control a motor, to start the motor with full voltage supply and then turn it down once it's moving.
So the Control Knob goes from OFF, to ON and then slower as rotated as it's increasing the resistance of the switch.
Stevie R wrote: Mon Oct 14, 2024 9:22 pm My Moggy has the smiths circular heater it’s a bit tired and could probably do with replacing, not had much experience in this field and I was wondering if there is an alternative that I can replace it with without too much of a faff
What do you mean by 'tired'?
It could be the switch that is wearing out or it might just need a clean if it's dirty so offering too much resistance to the current flow.
Equally, it is a motor, and I don't know without taking one apart if it's brushless or not, but I would guess that it is from Firedrake's image.
So a motor is probably an easy replacement if needed.
Basil the 1955 series II

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svenedin
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Re: Smiths heater replacement

Post by svenedin »

geoberni wrote: Tue Oct 15, 2024 11:16 am
Stevie R wrote: Tue Oct 15, 2024 9:20 am Thanks for the info @firedrake1942 I’ll give what you suggested a try looking at info on some platforms it says turn the button fully clockwise and then turn it back anticlockwise approx 1/2 inch and that’s on full, another says do the opposite?
Whether the heater is a Smiths, or an aftermarket like my Tudor, they are controlled by a Rheostat, which is basically a wire wound variable resistor on a ceramic former, a ring in the case of car heaters.
It's convention, for reasons I won't bother you with, when using such a resistive switch to control a motor, to start the motor with full voltage supply and then turn it down once it's moving.
So the Control Knob goes from OFF, to ON and then slower as rotated as it's increasing the resistance of the switch.
Stevie R wrote: Mon Oct 14, 2024 9:22 pm My Moggy has the smiths circular heater it’s a bit tired and could probably do with replacing, not had much experience in this field and I was wondering if there is an alternative that I can replace it with without too much of a faff
What do you mean by 'tired'?
It could be the switch that is wearing out or it might just need a clean if it's dirty so offering too much resistance to the current flow.
Equally, it is a motor, and I don't know without taking one apart if it's brushless or not, but I would guess that it is from Firedrake's image.
So a motor is probably an easy replacement if needed.
The motor, made by Smiths, is similar to the motor in the later rectangular heater and has standard carbon brushes which wear out. The motor can be serviced or there are modern replacement motors available. There are also "upgrades" possible whilst keeping the same type of heater. Expensive. https://claytonclassics.co.uk/parts-upg ... r-heaters/
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
amberbs
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Re: Smiths heater replacement

Post by amberbs »

you got it fixed?
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