Thermostat for Heater

[Kevin M Brown]

Working on the wiring in my new shop... I have a 220V / 5 kW ceiling-mount fan heater that I want to use to keep the shop at about 50-degrees in the winter. I want to put it on a programmable thermostat, so that it says at 50 during the week, but bumps up to 65 Saturday morning so that that it's nice and comfy when I get back into the shop.

Electrician I consulted says they don't make thermostats for that high voltage / amperage. Yet surely there is a solution for this one of you have already thought of?

Help me out, fellow cold-weather woodworkers! Solutions that don't require 4 hours of wiring or the fear that I will ignite anything will be preferred .

- Kevin in Chardon, OH

[Van Huskey]

Working on the wiring in my new shop... I have a 220V / 5 kW ceiling-mount fan heater that I want to use to keep the shop at about 50-degrees in the winter. I want to put it on a programmable thermostat, so that it says at 50 during the week, but bumps up to 65 Saturday morning so that that it's nice and comfy when I get back into the shop.

Electrician I consulted says they don't make thermostats for that high voltage / amperage. Yet surely there is a solution for this one of you have already thought of?

Help me out, fellow cold-weather woodworkers! Solutions that don't require 4 hours of wiring or the fear that I will ignite anything will be preferred .

- Kevin in Chardon, OH

They ABSOLUTELY do make 220 "line voltage" programmable thermostats. People use them for baseboard heat all the time however I don't know where to get them or 100% they will work for your situation.

edit:

A quick google came up with this and a lot more: http://www.amazon.com/King-ESP230-R-...pr_product_top http://air-n-water.stores.yahoo.net/hot4livoth4w.html

There seems to be a single pole vs double pole issue that you will need to sort out.

second edit:

The second one shows 16 amps, not enough for you but the first one shows 22 amps which if my math is correct is just about what you should be drawing. But you need to be sure and there are probably ones designed for higher current as well.

third edit:

here is one in the King catalog (not the same as the Amazon one) http://www.king-electric.com/prodtem..._ESP120-ESP230 and it shows my math was indeed correct here it is for sale for $50 http://www.prosupplyco.com/esp230-7d...40v22amps.aspx

there is also a option to use a transformer relay and use a standard low voltage thermostat, although if the above unit works this would be more expensive http://www.king-electric.com/prodtem...odID=TSTAT_24A

[Kevin M Brown]

They ABSOLUTELY do make 220 "line voltage" programmable thermostats. People use them for baseboard heat all the time however I don't know where to get them or 100% they will work for your situation.

Thanks... I've seen the baseboard heater thermostats, but the highest Watt rating I could find was 3,500, and my heater is a 5 kW heater... I suppose I could move the jumpers on the heater to move it down to 3,500 watts, but was hoping for another solution...

[Van Huskey]

Read all my edits, they have them up to 22 amps and the relay option runs you to 50 amps. But 22 amps should be perfect for you.

[Bill Edwards(2)]

My P-TAC is 220V and 3.5KW and a remote thermostat is available.

[Van Huskey]

My P-TAC is 220V and 3.5KW and a remote thermostat is available.

AFAIK all PTAC units use 24v thermostats or you can get wireless ones as well for some of them.

[ray hampton]

Working on the wiring in my new shop... I have a 220V / 5 kW ceiling-mount fan heater that I want to use to keep the shop at about 50-degrees in the winter. I want to put it on a programmable thermostat, so that it says at 50 during the week, but bumps up to 65 Saturday morning so that that it's nice and comfy when I get back into the shop.

Electrician I consulted says they don't make thermostats for that high voltage / amperage. Yet surely there is a solution for this one of you have already thought of?

Help me out, fellow cold-weather woodworkers! Solutions that don't require 4 hours of wiring or the fear that I will ignite anything will be preferred .

- Kevin in Chardon, OH

your electric man are right the thermostats are not 220 volts but 12/24 volts, what good will a electric furnace be as heating your home if it are not control by a thermostat, most electric furnaces are 220 volts or higher

[Van Huskey]

your electric man are right the thermostats are not 220 volts but 12/24 volts, what good will a electric furnace be as heating your home if it are not control by a thermostat, most electric furnaces are 220 volts or higher

Standard electric heat/AC and heat pumps do indeed use a 24v thermostat, however, there are such things as line voltage thermostats used with baseboard heat etc. They switch the 120/240V without using a relay like in a 24v system and 120/240V actually runs through the thermostat itself. You can pick up non-programmable line level thermostats at the BORGs.

[Corey Filkins]

Take a look at the Aube line voltage thermostats. They are made for electric radiant floor heat systems. Honeywell owns them so you should be able to get them anywhere.


Digital with a display and seven day programmable. They make two main models on with gfi one without.

Ebay is the lowest cost place for them.

[ray hampton]

Standard electric heat/AC and heat pumps do indeed use a 24v thermostat, however, there are such things as line voltage thermostats used with baseboard heat etc. They switch the 120/240V without using a relay like in a 24v system and 120/240V actually runs through the thermostat itself. You can pick up non-programmable line level thermostats at the BORGs.

Now I got a question , is high voltage thermostats wired series or parallel with the heater coils ? water heaters [electric] and stoves are turn on or off by thermostats

[Don Jarvie]

The wall thermostat is going to replace the one in the unit so basically out of the heater through the thermostat and then back in the heater. I got a Honeywell Double pole for my heater at grainger and it works fine.

If you have a Dayton G73 or similar model there is a post on how to wire in a wall thermostat.

[Corey Filkins]

You can also run a standard 24 volt thermostat into an isolation relay and have that relay switch the line voltage on and off. Functional devices makes a product called a relay in a box RIB that is a good fit.

I work in the HVAC field and we use these all the time.

[Van Huskey]

You can also run a standard 24 volt thermostat into an isolation relay and have that relay switch the line voltage on and off. Functional devices makes a product called a relay in a box RIB that is a good fit.

I work in the HVAC field and we use these all the time.

I linked to something like that above. What is the advantage to this other than keeping the line voltage wire runs shorter since it would seem to have to save a lot of wire to cover the cost of a low voltage thermostat and a relay as well. I did see that the relays can be had for higher amperage then the line voltage thermostats so that is obviously one advantage. Any more?

[Ken Cohen]

I also used a 24v/220 relay (also called a contactor). Two advantages as I saw it: wire savings and wider array of low voltage thermostat options.

Did it as a DIY project (under electrician guidance). Not hard, but not a rank beginner project. In my case, needed metal housing for relay next to heater.

[Corey Filkins]

The nice thing is you isolate the high voltage from thermostat and from touching it. Some relays also have a hand off auto switch and test button that allows to test the circuit or force the unit on.

I have the boiler in my house wired up this way. It allows me to use A nice touchscreen stat some of the more basic ones out there.