digital thermostatic timer

[Cactusgirl]

Saw one of those mentined on a post by a member and found Direct Trade Supplies electrical site selling them for £20. It has a 1000 hour battery back up should the electirc fail..which seems like a good idea but then if the electric fails the heater wont switch on anyway! I have only got a temporary 2kw heater operating in half of my greenhouse (its a 16x8) as I only have a few plants at present so have sectioned it off into two. I'm looking to get a more powerful heater suitable for the whole area ready for when I need it (certainly next year) and have seen a 2.5kw Honeywell on the Machine Mart website which has some very good reviews. I've got electrics in the greenhouse which were professionally installed so wiring is not a problem. Cant post a link re the heater as unsure how to. However, I'm thinking that one of the Honeywell heaters with the digital thermostatic timer and a well insulated greenhouse should help to keep it at around 5/6 degrees thru winter? I'm situated in the East close to the Suffolk/Essex border.

[Jim_Mercer]

If you mean this one https://www.machinemart.co.uk/c/electri ... =honeywell I can't see any mention of it being splash proof. Heaters should have IP rating eg IP44 - first digit refers to protection from objects entering and second is the more important one for greenhouse use as it is about water. Higher numbers are better with 4 being splashing water. Beware of some of the heaters from China which come with various brand names as I have seen reviews complaining that they claimed a higher splash rating on sales page than was actually marked on the heater

[Diane]

I agree with Jim - this is sold as a room heater, so probably not safe to use in a greenhouse.

[ChrisR]

Just my opinion of course......but I don't concern myself with all this IP44 stuff. I've used regular fan heaters for years and think those "especially made" for greenhouse use are just a rip off. Firstly, who sprays water all over their electric greenhouse heater? Most cactus based collections are dry in winter anyway. If Cactusgirl has professionally installed electrics they will be RCD protected she she wouldn't kill herself were she daft enough to water her heater and then touch it. I'm currently using two 2kw heaters from Screwfix which have worked admirably for 5 years for a very modest outlay and there's no reason why the similar Machine Mart heaters should be just as good.

And I'm an electrician (retired).

[Cactusgirl]

Very interesting Chris thanks for that. I have looked at two 'greenhouse' heaters - Hot Box and Bio green Phoenix. Supplier won't recommend the Bio due to bad aftercare service and the Hot Box isn't IP rated anyway! Both are £200 each. I will spend this if needed due to value of plants but if I can get something else which does the same job for less cash then I will. If you can message me with details for those you use I would be very interested please?
Thanks
Debbie

[ragamala]

Firstly, who sprays water all over their electric greenhouse heater? Most cactus based collections are dry in winter anyway.

Me when I use it as fan-only summer cooling. I tend to splash around quite a bit when watering.....

Although I agree in principle.

[ChrisR]

I take them out after winter as I use high level cooling.

[habanerocat]

Saw one of those mentined on a post by a member and found Direct Trade Supplies electrical site selling them for £20. It has a 1000 hour battery back up should the electirc fail..which seems like a good idea but then if the electric fails the heater wont switch on anyway!

The backup battery of our digital thermostatic timer stores switching temperatures and times. Saves you reprogramming them after a power failure - but I see your point. If power goes in your house, you're sure to notice, but a trip switch could fail to your greenhouse which may not be immediately noticed. No harm having a trip alarm fitted if overly concerned.

[ragamala]

Both are £200 each. I will spend this if needed due to value of plants but if I can get something else which does the same job for less cash then I will.

I agree with Chris, some of these heaters are just overexpensive. What's a heater anyway? Just like a kettle element with a fan behind it.

Take this as just one example.

https://www.amazon.co.uk/Hawk-Tools-Ele ... mostat+13A

You could add a thermostat control with 1.5m sensor cable eg BioGreen Thermo 2 and still end up at around half the Phoenix cost.

Or have you considered supplementing your existing 2kw heater with a second one (see eg German-built TDS10, which I use very happily - it has three fan settings which means with two of these heaters you can come under 13/15A if necessary) and buying thermostats for each (Inkjet 308 is good, more facilities than Biogreen Thermo 2 and half the price, only drawback comparatively is it will only feed 10A, ie a 1/2kw heater rather than a 3kw heater. At £27 each for the thermostats and £25 for another heater (or £50 for 2! - and that TDS is IPX4 rated) again you are coming in with IMO a good solution around £100 or less. This just might have the advantage of backup in case of single heater failure, or having different temperatures in different parts of the greenhouse.

https://www.manomano.co.uk/electric-por ... id=1372450

https://www.amazon.co.uk/Inkbird-Temper ... 018K82UQU/

[D^L]

I agree that with greenhouse products you pay a lot for convenience and limited extra safeguards. I'd just point out that Chris and Ragamala obviously know what they are doing when they patch up their own systems. Beware that you require basic knowledge and skills before embarking on such things.
I doubt anyone would deliberately water the heater but beware of: leaks, condensation, accidents, neighbours helping if you are away...
Take appropriate care with electricity and water and, if you don't know about it, get professional help. Chris has that already☺
Cheers
David Lambie
Bristol