Heating questions

[DisturbedDave]

I have heard good things about Carel thermostats but they cost about $350, but they last.

Are they reptile specific stats? Carel refrigeration digital stats shouldn't set you back more than $150, wouldn't imagine it would be much more, unless it has special features

 

[andynic07]

Are they reptile specific stats? Carel refrigeration digital stats shouldn't set you back more than $150, wouldn't imagine it would be much more, unless it has special features

I am not 100% sure. Micheal Cermak (Watterat) said that he bought some about 8 years for his incubators for $350 each and they have never missed a beat and are perfectly calibrated. This is the picture of the link he posted.

 

[DisturbedDave]

You could try going to Actrol (refrigeration wholesaler, they are agents for Carel ), and getting a price through them. Might be worth doing research on the model needed before going in there and getting them to look it up (they'll charge you more). Might save a bit of coin this way

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[andynic07]

You could try going to Actrol (refrigeration wholesaler, they are agents for Carel ), and getting a price through them. Might be worth doing research on the model needed before going in there and getting them to look it up (they'll charge you more). Might save a bit of coin this way

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Cheers mate, I certainly will do some more thorough research before I change thermostats, whilst mine are working I am going to stick with them.

 

[Lawra]

I hope this isn't too off topic, since you're discussing dimming thermostats. I am wondering if you've ever had an on/off thermostat fail and stay on?

 

[Chris1]

ive had 3 thermostats fail, each time they turned the heat source off. (2 dimming, 1 pulse proportional)

 

[Bushman]

This is a good discussion guys. I might take advantage of the expertise present. 8)
I've heard about setting up thermostats in a series, as added protection if one fails.
Can someone kindly advise as to how to go about this?

 

[saximus]

To have them in series all you would need to do is connect the input (the part that normally goes into the wall) for thermo A into the output (the part that normally connects to the heater) of thermo B. Then you would probably set thermo B to a higher temp so that it is the backup. In that case, with everything working normally, thermo A would be the main controller and thermo B would always be on. Then is thermo A fails in a way that causes it to stay on, thermo B would kick in and shut everything off. I hope that isn't confusing :/

 

[andynic07]

To have them in series all you would need to do is connect the input (the part that normally goes into the wall) for thermo A into the output (the part that normally connects to the heater) of thermo B. Then you would probably set thermo B to a higher temp so that it is the backup. In that case, with everything working normally, thermo A would be the main controller and thermo B would always be on. Then is thermo A fails in a way that causes it to stay on, thermo B would kick in and shut everything off. I hope that isn't confusing :/

This is right but not sure how effective this would be in the event that the first thermostat fails and stays on because you would not know it had failed until it was needed and then it would be too late. Maybe someone like yourself could design a monitoring circuit that would just shut off supply to the thermostat if a certain temperature was reached, this way your reptile would have no heat until you noticed a led had gone out and you would realise something had gone wrong. This is only one idea as well and you may have something a little more appropriate in mind.

 

[Bushman]

Thanks Saximus. That's well explained. I think I'll employ this strategy as a fail safe until I can get my hands on one of those Carell thermostats, which sound like the top of the range in heating control.

 

[saximus]

Maybe someone like yourself could design a monitoring circuit that would just shut off supply to the thermostat if a certain temperature was reached

That's the point of redundancy though. I understand what you're saying about not knowing it has failed but a simple test every now and then would help with that. Without getting too nerdy and getting into the maths it’s a bit tricky to explain but this system has reduced your chance of failure from the chance of failure of a single thermo to the combined chance of failure of both thermos. Adding a monitoring system would simply add a third level of redundancy but can never produce a 100% guarantee.

 

[andynic07]

That's the point of redundancy though. I understand what you're saying about not knowing it has failed but a simple test every now and then would help with that. Without getting too nerdy and getting into the maths it’s a bit tricky to explain but this system has reduced your chance of failure from the chance of failure of a single thermo to the combined chance of failure of both thermos. Adding a monitoring system would simply add a third level of redundancy but can never produce a 100% guarantee.

Fair enough, I was thinking of the monitoring circuit instead of the second thermostat but it is probably easier to just buy a second cheap switching thermostat to effectively reduce the chances of failure.