DP Thermostat - Thermostatically Break BOTH Lines - Electrical - DIY Chatroom Home Improvement Forum
Advertisement


Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Electrical

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools
Display Modes
Old 10-21-2010, 11:40 AM   #1
Newbie
 
Join Date: Oct 2010
Posts: 2
Rewards Points: 10
Default

DP Thermostat - thermostatically break BOTH lines


I need a DP thermostat that thermostatically breaks BOTH lines. i.e. the Honeywell T410B or Dimplex TD 322W only break one line thermostatically and the other is only broken in the OFF position.

I am using the thermostat to control a 24 VAC zone control valve and simultaneously turn on a 115 V fan switch. in a hydronic heating system.
docdoor is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 10-21-2010, 12:45 PM   #2
Member
 
Join Date: Nov 2007
Location: Nashua, NH, USA
Posts: 8,597
Rewards Points: 2,800
Default


You should get a contactor (relay) that uses one input and can switch two other circuits on or off as needed. The input (feeds a coil) must accept the voltage and amperage (current) that the existing thermostat provides.

They make direct switching (line voltage) thermostats used with electric baseboard heat. Usually each has two built in switches. You could use one half of the thermostat for the 24 volt circuit and the other half for the 115 volt circuit.

But the two switches usually don't click on and off at precisely the same time or temperature.
__________________
Stick to your lawn watering schedule until it really starts to pour. After the storm you have only the same number of rest days you always had and then you need to start watering again.
AllanJ is offline   Reply With Quote
The Following User Says Thank You to AllanJ For This Useful Post:
docdoor (10-21-2010)
Sponsored Links
Advertisement
 
Old 10-21-2010, 01:06 PM   #3
Licensed electrician
 
Join Date: Sep 2007
Location: Maryland
Posts: 12,410
Rewards Points: 3,662
Default


I must be missing something here, but, this sounds like for baseboard heaters.

A SP t-stat only breaks one side. A double pole t-stat breaks both sides. Both should be readily available.
__________________
Answers based on the National Electrical Code. Local amendments may apply. Check with your local building officials.
Jim Port is online now   Reply With Quote
The Following User Says Thank You to Jim Port For This Useful Post:
docdoor (10-21-2010)
Sponsored Links
Advertisement
 
Old 10-21-2010, 02:02 PM   #4
Newbie
 
Join Date: Oct 2010
Posts: 2
Rewards Points: 10
Default

DP Thermostat


The thermostats that are advertised as DP i.e. Honeywell CT410B or Dimplex TD322W are not truly DP in the sense that the poles don't switch simultaneously as with a relay, they are more or less two switches one that is thermostatically controlled (only one of the lines, black wires), and the other (line, red wires) that is not, in that it only cuts the power to the device (of the one line, red wires) in the OFF position. in other words when the thermostat is not calling for heat one line will be disconnected (black wires) but the other line will not (red wires), thus allowing voltage to the device along the one line (red wires). I don't need simultaneous activation, a slight delay would be acceptable. Now in my application I am attempting to control two separate devices thermostatically, one is 115VAC (fan) and the other 24VAC (solenoid valve).
docdoor is offline   Reply With Quote
Old 10-21-2010, 02:54 PM   #5
A "Handy Husband"
 
rjniles's Avatar
 
Join Date: Feb 2007
Location: South Carolina Low Country
Posts: 10,028
Rewards Points: 704
Default


Use the T-stat to control a DPST contactor (relay) with a 24 volt coil and contacts rated for 120 volts. Use one contact for the zone valve(24 VAC) and the other for the fan(120 VAC).
__________________
My electrical answers are based on 2014 NEC, you may have local amendments.

Location: Coastal South Carolina
rjniles is online now   Reply With Quote
The Following User Says Thank You to rjniles For This Useful Post:
docdoor (10-21-2010)
Sponsored Links
Advertisement
 
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Carrier Edge Thermostat Installation Issue ptalar HVAC 1 07-13-2010 05:40 PM
Honeywell Prestige HD thermostat wiring 1H/1C + Humidification System TekGamer HVAC 0 07-09-2010 11:58 PM
Problem with Lennox Pulse Furnace Wiring to Thermostat scalvin Electrical 4 12-30-2009 07:48 PM
Replacing thermostat...................... sktn77a HVAC 6 09-02-2009 10:07 PM
Thermostat from Manual to Digital trinamillersmit HVAC 5 07-02-2009 09:21 AM




Top of Page | View New Posts