Which frost thermostat

try to avoid anything with a battery in, when it gets really cold the battery will not be able to produce 1.5V and the thermostat will reset and not work.

Its a bit of extra trouble but you really need to wire one of these in. http://www.ebay.co.uk/itm/10-AMP-AN...arden_Hearing_Cooling_Air&hash=item2c6185fffd
which isnt affected by power loss.


And yes I realise in theory it shouldnt ever get as cold as that but it will do as soon as the temp drops all the stinkers and live aboards demand power and the whole pontoon trips out, the night watchman will have the job to sort it out while getting his danglies frozen off !
Easy solution is to unplug all the boats without anyone on and leave the live aboards to plug them back in the morning.

Personally I believe you need to antifreeze the engine and leave the saloon cold but dehumidified.
Warm saloon will allow mould to flourish.
 
So where does all this murderous saturated air come from? I reckon 90% of it is from your breath and then it only appears on cold days. My theory is that without humans on board the humidity is of no consequence. Just a thought.

Apologies for the thread drift.
 
gravygraham said:
So where does all this murderous saturated air come from? I reckon 90% of it is from your breath and then it only appears on cold days. My theory is that without humans on board the humidity is of no consequence. Just a thought.

Apologies for the thread drift.
Click to expand...

I dont think it is thread drift, good point and is what I tried to point out.


Cold glass window.

Warm heated saloon.

condensates like a bottle of Moet (sports boat owners read as can of beer).

drips onto curtains/sofa bedding.

Dehumidifier takes the moister out , doesnt work when really cold but that doesnt matter as its dry and cold.
If it does condensate when cold it doesnt produce mould.
Mould needs warm but as soon as warm the dehumidifier will take the moisture away.
 
Yes, the TLC ET05 is about £15, and great bit of kit, if your remember to keep the internal battery charged over the summer. It will not discharge in a few days if you have an outage, and will not lose its settings to my knowledge, as it is a relatively simple bit of kit.
 
DAKA said:
Personally I believe you need to antifreeze the engine and leave the saloon cold but dehumidified.
Warm saloon will allow mould to flourish.
Click to expand...

I agree with you Daka. Going against the grain of thought on this thread somewhat, but if it's really cold (thinking of the -7C one night last year at the marina) I'm not convinced a piddly little 100w tube heater is going to save the engines from freezing, esp sterndrive boats where the engines are arguably more exposed than on shaft. Unless all the engine room vents are sealed up any warmth will disappear like a fart in the wind, so that is a "must do", but in any case if the lecky goes off, you've no protection. Last year I had frozen pipes in the heads despite the presence of 1kw oil filled radiator less then 3' away, whilst the boat was afloat too in its 'warm' bath of seawater.

So this year the engines are being flushed through with a/f whilst on the hard and vulnerable, then I can sleep easy and I'm not going bother trying and heat it. Indeed, my insurers will only cover frost damage to the engines if they are flushed with a/f; so a bit of a no brainer really. Cost is a bit of a/f and half an hour engineer time. Sorted.

As to the saloon, I have a dessicant dehumidifier which works at low temps plus my 1kw heater, but set to keep the temp hopefully above freezing and not warm enough to permit the creation of condensation.
 
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sailorman said:
x 2 £s of any previously mentioned :D
Click to expand...

yep but you do get a little monitor thingy on a lead to place on the engine itself rather than monitoring the air temperature and these things are built for outside places like greenhouses so are water proof and hopefully more robust electronically than the plug in jobs which are no doubt intended for internal use only. It should also allow me to change the connectors e.g. pop a 110v style connector on one end to go in to the shore power rather than via the boats outlets and change the single socket to a double on the other end that'll go in the engine bay to run > 1 heater

I've gawn and purchased it myself for those reasons, an extra 20 quid to give a little more protection against £1,000's invested in green lumps seems a good investment to me.

I should be able to hang a couple of 1kw oil filled radiators off this thing without it going pop with it being a 10amp rated unit
 
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AdeOlly said:
I agree with you Daka. Going against the grain of thought on this thread somewhat, but if it's really cold (thinking of the -7C one night last year at the marina) I'm not convinced a piddly little 100w tube heater is going to save the engines from freezing, esp sterndrive boats where the engines are arguably more exposed than on shaft. Unless all the engine room vents are sealed up any warmth will disappear like a fart in the wind, so that is a "must do", but in any case if the lecky goes off, you've no protection. Last year I had frozen pipes in the heads despite the presence of 1kw oil filled radiator less then 3' away, whilst the boat was afloat too in its 'warm' bath of seawater.

So this year the engines are being flushed through with a/f whilst on the hard and vulnerable, then I can sleep easy and I'm not going bother trying and heat it. Indeed, my insurers will only cover frost damage to the engines if they are flushed with a/f; so a bit of a no brainer really. Cost is a bit of a/f and half an hour engineer time. Sorted.

As to the saloon, I have a dessicant dehumidifier which works at low temps plus my 1kw heater, but set to keep the temp hopefully above freezing and not warm enough to permit the creation of condensation.
Click to expand...

We had -19C in our (Freshwater) marina 2 years ago, and with 2x120W heaters, the engine bay was above freezing in Rafiki. The sterndrives were in the water, which was iced up for 42 days, but there is sufficient room in the water galleries for the ice to form without damage fortunately.
 
rafiki_ said:
We had -19C in our (Freshwater) marina 2 years ago, and with 2x120W heaters, the engine bay was above freezing in Rafiki. The sterndrives were in the water, which was iced up for 42 days, but there is sufficient room in the water galleries for the ice to form without damage fortunately.
Click to expand...

Rafiki's must have very good engine bay insulation - I take it you blocked off the air intakes?
 
David2452 said:
There is a specific frost stat available as an accessory from Webasto but we normally only fit them on coolant based systems.
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That's very interesting - any reason why it could not be fitted to an AirTop? Does it just wire in parallel with the main thermostat? Any special fitting requirements?
 
maby said:
That's very interesting - any reason why it could not be fitted to an AirTop? Does it just wire in parallel with the main thermostat? Any special fitting requirements?
Click to expand...

No reason at all, it's only a switch, there is no thermostat on an AT, they have a rheostat and an intermal or external temperature sensorr. But yes is the simple answer but some modification of the harness is required.
 
David2452 said:
No reason at all, it's only a switch, there is no thermostat on an AT, they have a rheostat and an intermal or external temperature sensorr. But yes is the simple answer but some modification of the harness is required.
Click to expand...

You had me puzzled on first reading with "... no thermostat on an AT..." you are more literal in your definition of a thermostat than I - there is a box of electronics with a knob (rheostat) and temperature sensor which combine to produce the functionality of a thermostat...

is the modification to the wiring harness documented anywhere? I would really like to fit one to our boat - the setting of the knob on the control panel is a little hit and miss - not easy to be sure of the temperature I am selecting. If I could drop one of those frost stats in and not have to worry about the temperture control, I would really like it!
 
maby said:
You had me puzzled on first reading with "... no thermostat on an AT..." you are more literal in your definition of a thermostat than I - there is a box of electronics with a knob (rheostat) and temperature sensor which combine to produce the functionality of a thermostat...

is the modification to the wiring harness documented anywhere? I would really like to fit one to our boat - the setting of the knob on the control panel is a little hit and miss - not easy to be sure of the temperature I am selecting. If I could drop one of those frost stats in and not have to worry about the temperture control, I would really like it!
Click to expand...

It is certainly not documented in any of the partial manuals available for download openly, precisely what year and model AT do you have? I will have a look at the standard cabling for that and see if I can come up with a solution, it will be possible but will have nothing to do with the rheostat or temperature sensors, more likely be linked to a telestart lead as with the TTC, my description is not meant to be literal but rather to be technically correct and avoid doubt.
 
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David2452 said:
It is not documented in any of the partial manuals abailable for download, precisely what year and model AT do you have? I will have a look at the standard cabling for that and see if I can come up with a solution, it will be possible but will have nothing to do with the rheostat or temperature sensors, more likely be linked to a telestart lead as with the TTC, my description is not meant to be literal but rather to be technically correct and avoid doubt.
Click to expand...

It's an Airtop EVO just over a year old. I'm not certain about the size, but strongly believe it's the 3900. It has the standard EVO control panel fitted with external thermo-sensor located in the salon and no timer.
 
oGaryo said:
how about something like this... Greenhouse Thermostat
Click to expand...

Well, the double the price thermostat in waterproof housing arrived earlier today and have to say I am impressed with it, looks a solid unit... the thermostat itself can be swapped out if it goes unservicable,

A few mods made using sticky black plastic and fairy liquid bottles and hey presto, a decent bit of kit to go in the boat when next down there. :D

The standard household plug has been replaced with a slim 10amp 3 pin connector used between the orange cable and main unit to allow it to fit easily through the engine bay air vents. I've also replaced the extension lead single socket with a double waterproof socket to run two heaters so will still have heat if one heater should fail.

I'll fix the main unit and double socket permanently inside the engine bay

559013_4070140391780_1873450816_n.jpg


p.s. 3 pin household plug and extension lead socket going on Ebay tonight complete with 2in of cord.. keep your eye out for it, grab a bargain, only 40 quid
 
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oGaryo said:
Well, the double the price thermostat in waterproof housing arrived earlier today and have to say I am impressed with it, looks a solid unit... the thermostat itself can be swapped out if it goes unservicable,

A few mods made using sticky black plastic and fairy liquid bottles and hey presto, a decent bit of kit to go in the boat when next down there. :D

The standard household plug has been replaced with a slim 10amp 3 pin connector used between the orange cable and main unit to allow it to fit easily through the engine bay air vents. I've also replaced the extension lead single socket with a double waterproof socket to run two heaters so will still have heat if one heater should fail.

I'll fix the main unit and double socket permanently inside the engine bay

559013_4070140391780_1873450816_n.jpg


p.s. 3 pin household plug and extension lead socket going on Ebay tonight complete with 2in of cord.. keep your eye out for it, grab a bargain, only 40 quid
Click to expand...
Nice job Gary. You know what to do if the day job goes:)
 
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