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How many wires should be in a new thermostat cable?
Adding a C wire to a new Honeywell WIfi ThermostatHow can I wire my WIFI thermostat to control my millivolt fireplace?Need help adding a C wire for a wifi thermostatHow can I connect a WIFI thermostat to a Honeywell R845A switching relay?How to move from RH/RC thermostat to C thermostat in AC only system?How to wire A/C Thermostat given different wiring conventionsHow do a replace an old baseboard thermostat with a wifi thermostat?How should I hook up my WiFi thermostat given my current wiring situation?How to connect wifi thermostat with a boiler after cable upgrade?Do they make 24v transformers that have individual terminals for up to 4 thermostats?
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When roughing in thermostat wire, how many pair wire would you use to cover most thermostats?
I'm asking because keep seeing questions about C wire and wifi.
wiring thermostat thermostat-c-wire
New contributor
add a comment |
When roughing in thermostat wire, how many pair wire would you use to cover most thermostats?
I'm asking because keep seeing questions about C wire and wifi.
wiring thermostat thermostat-c-wire
New contributor
WiFi is actually quite the opposite - cuts down on the need for wires. But typical is a WiFi thermostat in the location of a regular thermostat - same number of wires as "normal". Also, unlike phone/ethernet/etc., thermostat wire is a bunch of separate wires, not actually pairs.
– manassehkatz
3 hours ago
1
What is normal,? No less than 5.
– Robert Moody
11 mins ago
add a comment |
When roughing in thermostat wire, how many pair wire would you use to cover most thermostats?
I'm asking because keep seeing questions about C wire and wifi.
wiring thermostat thermostat-c-wire
New contributor
When roughing in thermostat wire, how many pair wire would you use to cover most thermostats?
I'm asking because keep seeing questions about C wire and wifi.
wiring thermostat thermostat-c-wire
wiring thermostat thermostat-c-wire
New contributor
New contributor
edited 3 hours ago
isherwood
52.7k462136
52.7k462136
New contributor
asked 4 hours ago
Robert MoodyRobert Moody
84
84
New contributor
New contributor
WiFi is actually quite the opposite - cuts down on the need for wires. But typical is a WiFi thermostat in the location of a regular thermostat - same number of wires as "normal". Also, unlike phone/ethernet/etc., thermostat wire is a bunch of separate wires, not actually pairs.
– manassehkatz
3 hours ago
1
What is normal,? No less than 5.
– Robert Moody
11 mins ago
add a comment |
WiFi is actually quite the opposite - cuts down on the need for wires. But typical is a WiFi thermostat in the location of a regular thermostat - same number of wires as "normal". Also, unlike phone/ethernet/etc., thermostat wire is a bunch of separate wires, not actually pairs.
– manassehkatz
3 hours ago
1
What is normal,? No less than 5.
– Robert Moody
11 mins ago
WiFi is actually quite the opposite - cuts down on the need for wires. But typical is a WiFi thermostat in the location of a regular thermostat - same number of wires as "normal". Also, unlike phone/ethernet/etc., thermostat wire is a bunch of separate wires, not actually pairs.
– manassehkatz
3 hours ago
WiFi is actually quite the opposite - cuts down on the need for wires. But typical is a WiFi thermostat in the location of a regular thermostat - same number of wires as "normal". Also, unlike phone/ethernet/etc., thermostat wire is a bunch of separate wires, not actually pairs.
– manassehkatz
3 hours ago
1
1
What is normal,? No less than 5.
– Robert Moody
11 mins ago
What is normal,? No less than 5.
– Robert Moody
11 mins ago
add a comment |
2 Answers
2
active
oldest
votes
If you're building a new building and having new HVAC installed, I would simply put 1/2" conduit in the wall and be done. That way, you let the installer run the wire they need. I don't know that I would do this without at least consulting an HVAC installer to see where they would put the unit and the air return (typically the thermostat is as near the return as possible).
If you're going to just pre-run wire and dictate where the return will be and the HVAC unit will sit, I would run 18/5 wire if you know you will have a AC + gas heat, and 18/8 if you know you will have a heat pump (if you're in doubt, more will not hurt). Your most basic setup on most modern units needs 4 control wires plus the fifth blue "C" wire that provides power to the thermostat. It won't cover anything elaborate like a heat pump, but your greatest risk would be the installer uses your wire to pull the wire they actually need.
1
If running a cable instead of putting in conduit, I would err on the side of "extra". We're talking about literally just a few dollars for a typical run between 18/5 and 18/8. If the installer ends up needing more than a basic 5 wires, it will cost a lot more to fix it later.
– manassehkatz
3 hours ago
1
Is extra bad? 5 seems to be ok 8 seems to cover the unknown.
– Robert Moody
3 hours ago
1
@RobertMoody Not at all. Costs a bit more is all
– Machavity
1 hour ago
add a comment |
I'd use 20/8 which is pretty standard today. That will cover anything up to a 2-stage heat pump system. I'm not sure how WiFi factors in here. An smart/electronic thermostat like a Nest does support WiFi but not between the HVAC unit and the thermostat.
When using 20/8 does it leave extra wires in case one gets nicked?
– Robert Moody
3 hours ago
It's not common to run extra wires in anticipation of damage. If you expect it, run conduit.
– isherwood
3 hours ago
Not so much anticipation of damage.But for the future.
– Robert Moody
3 hours ago
1
"FOR THE FUTURE", RUN CONDUIT NOW. Conduit is the most future-proof technology there is for wiring. Pull out the obsolete, pull in the up to date, done.
– Ecnerwal
2 hours ago
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
If you're building a new building and having new HVAC installed, I would simply put 1/2" conduit in the wall and be done. That way, you let the installer run the wire they need. I don't know that I would do this without at least consulting an HVAC installer to see where they would put the unit and the air return (typically the thermostat is as near the return as possible).
If you're going to just pre-run wire and dictate where the return will be and the HVAC unit will sit, I would run 18/5 wire if you know you will have a AC + gas heat, and 18/8 if you know you will have a heat pump (if you're in doubt, more will not hurt). Your most basic setup on most modern units needs 4 control wires plus the fifth blue "C" wire that provides power to the thermostat. It won't cover anything elaborate like a heat pump, but your greatest risk would be the installer uses your wire to pull the wire they actually need.
1
If running a cable instead of putting in conduit, I would err on the side of "extra". We're talking about literally just a few dollars for a typical run between 18/5 and 18/8. If the installer ends up needing more than a basic 5 wires, it will cost a lot more to fix it later.
– manassehkatz
3 hours ago
1
Is extra bad? 5 seems to be ok 8 seems to cover the unknown.
– Robert Moody
3 hours ago
1
@RobertMoody Not at all. Costs a bit more is all
– Machavity
1 hour ago
add a comment |
If you're building a new building and having new HVAC installed, I would simply put 1/2" conduit in the wall and be done. That way, you let the installer run the wire they need. I don't know that I would do this without at least consulting an HVAC installer to see where they would put the unit and the air return (typically the thermostat is as near the return as possible).
If you're going to just pre-run wire and dictate where the return will be and the HVAC unit will sit, I would run 18/5 wire if you know you will have a AC + gas heat, and 18/8 if you know you will have a heat pump (if you're in doubt, more will not hurt). Your most basic setup on most modern units needs 4 control wires plus the fifth blue "C" wire that provides power to the thermostat. It won't cover anything elaborate like a heat pump, but your greatest risk would be the installer uses your wire to pull the wire they actually need.
1
If running a cable instead of putting in conduit, I would err on the side of "extra". We're talking about literally just a few dollars for a typical run between 18/5 and 18/8. If the installer ends up needing more than a basic 5 wires, it will cost a lot more to fix it later.
– manassehkatz
3 hours ago
1
Is extra bad? 5 seems to be ok 8 seems to cover the unknown.
– Robert Moody
3 hours ago
1
@RobertMoody Not at all. Costs a bit more is all
– Machavity
1 hour ago
add a comment |
If you're building a new building and having new HVAC installed, I would simply put 1/2" conduit in the wall and be done. That way, you let the installer run the wire they need. I don't know that I would do this without at least consulting an HVAC installer to see where they would put the unit and the air return (typically the thermostat is as near the return as possible).
If you're going to just pre-run wire and dictate where the return will be and the HVAC unit will sit, I would run 18/5 wire if you know you will have a AC + gas heat, and 18/8 if you know you will have a heat pump (if you're in doubt, more will not hurt). Your most basic setup on most modern units needs 4 control wires plus the fifth blue "C" wire that provides power to the thermostat. It won't cover anything elaborate like a heat pump, but your greatest risk would be the installer uses your wire to pull the wire they actually need.
If you're building a new building and having new HVAC installed, I would simply put 1/2" conduit in the wall and be done. That way, you let the installer run the wire they need. I don't know that I would do this without at least consulting an HVAC installer to see where they would put the unit and the air return (typically the thermostat is as near the return as possible).
If you're going to just pre-run wire and dictate where the return will be and the HVAC unit will sit, I would run 18/5 wire if you know you will have a AC + gas heat, and 18/8 if you know you will have a heat pump (if you're in doubt, more will not hurt). Your most basic setup on most modern units needs 4 control wires plus the fifth blue "C" wire that provides power to the thermostat. It won't cover anything elaborate like a heat pump, but your greatest risk would be the installer uses your wire to pull the wire they actually need.
edited 1 hour ago
answered 3 hours ago
MachavityMachavity
8,87022043
8,87022043
1
If running a cable instead of putting in conduit, I would err on the side of "extra". We're talking about literally just a few dollars for a typical run between 18/5 and 18/8. If the installer ends up needing more than a basic 5 wires, it will cost a lot more to fix it later.
– manassehkatz
3 hours ago
1
Is extra bad? 5 seems to be ok 8 seems to cover the unknown.
– Robert Moody
3 hours ago
1
@RobertMoody Not at all. Costs a bit more is all
– Machavity
1 hour ago
add a comment |
1
If running a cable instead of putting in conduit, I would err on the side of "extra". We're talking about literally just a few dollars for a typical run between 18/5 and 18/8. If the installer ends up needing more than a basic 5 wires, it will cost a lot more to fix it later.
– manassehkatz
3 hours ago
1
Is extra bad? 5 seems to be ok 8 seems to cover the unknown.
– Robert Moody
3 hours ago
1
@RobertMoody Not at all. Costs a bit more is all
– Machavity
1 hour ago
1
1
If running a cable instead of putting in conduit, I would err on the side of "extra". We're talking about literally just a few dollars for a typical run between 18/5 and 18/8. If the installer ends up needing more than a basic 5 wires, it will cost a lot more to fix it later.
– manassehkatz
3 hours ago
If running a cable instead of putting in conduit, I would err on the side of "extra". We're talking about literally just a few dollars for a typical run between 18/5 and 18/8. If the installer ends up needing more than a basic 5 wires, it will cost a lot more to fix it later.
– manassehkatz
3 hours ago
1
1
Is extra bad? 5 seems to be ok 8 seems to cover the unknown.
– Robert Moody
3 hours ago
Is extra bad? 5 seems to be ok 8 seems to cover the unknown.
– Robert Moody
3 hours ago
1
1
@RobertMoody Not at all. Costs a bit more is all
– Machavity
1 hour ago
@RobertMoody Not at all. Costs a bit more is all
– Machavity
1 hour ago
add a comment |
I'd use 20/8 which is pretty standard today. That will cover anything up to a 2-stage heat pump system. I'm not sure how WiFi factors in here. An smart/electronic thermostat like a Nest does support WiFi but not between the HVAC unit and the thermostat.
When using 20/8 does it leave extra wires in case one gets nicked?
– Robert Moody
3 hours ago
It's not common to run extra wires in anticipation of damage. If you expect it, run conduit.
– isherwood
3 hours ago
Not so much anticipation of damage.But for the future.
– Robert Moody
3 hours ago
1
"FOR THE FUTURE", RUN CONDUIT NOW. Conduit is the most future-proof technology there is for wiring. Pull out the obsolete, pull in the up to date, done.
– Ecnerwal
2 hours ago
add a comment |
I'd use 20/8 which is pretty standard today. That will cover anything up to a 2-stage heat pump system. I'm not sure how WiFi factors in here. An smart/electronic thermostat like a Nest does support WiFi but not between the HVAC unit and the thermostat.
When using 20/8 does it leave extra wires in case one gets nicked?
– Robert Moody
3 hours ago
It's not common to run extra wires in anticipation of damage. If you expect it, run conduit.
– isherwood
3 hours ago
Not so much anticipation of damage.But for the future.
– Robert Moody
3 hours ago
1
"FOR THE FUTURE", RUN CONDUIT NOW. Conduit is the most future-proof technology there is for wiring. Pull out the obsolete, pull in the up to date, done.
– Ecnerwal
2 hours ago
add a comment |
I'd use 20/8 which is pretty standard today. That will cover anything up to a 2-stage heat pump system. I'm not sure how WiFi factors in here. An smart/electronic thermostat like a Nest does support WiFi but not between the HVAC unit and the thermostat.
I'd use 20/8 which is pretty standard today. That will cover anything up to a 2-stage heat pump system. I'm not sure how WiFi factors in here. An smart/electronic thermostat like a Nest does support WiFi but not between the HVAC unit and the thermostat.
answered 4 hours ago
jwh20jwh20
3274
3274
When using 20/8 does it leave extra wires in case one gets nicked?
– Robert Moody
3 hours ago
It's not common to run extra wires in anticipation of damage. If you expect it, run conduit.
– isherwood
3 hours ago
Not so much anticipation of damage.But for the future.
– Robert Moody
3 hours ago
1
"FOR THE FUTURE", RUN CONDUIT NOW. Conduit is the most future-proof technology there is for wiring. Pull out the obsolete, pull in the up to date, done.
– Ecnerwal
2 hours ago
add a comment |
When using 20/8 does it leave extra wires in case one gets nicked?
– Robert Moody
3 hours ago
It's not common to run extra wires in anticipation of damage. If you expect it, run conduit.
– isherwood
3 hours ago
Not so much anticipation of damage.But for the future.
– Robert Moody
3 hours ago
1
"FOR THE FUTURE", RUN CONDUIT NOW. Conduit is the most future-proof technology there is for wiring. Pull out the obsolete, pull in the up to date, done.
– Ecnerwal
2 hours ago
When using 20/8 does it leave extra wires in case one gets nicked?
– Robert Moody
3 hours ago
When using 20/8 does it leave extra wires in case one gets nicked?
– Robert Moody
3 hours ago
It's not common to run extra wires in anticipation of damage. If you expect it, run conduit.
– isherwood
3 hours ago
It's not common to run extra wires in anticipation of damage. If you expect it, run conduit.
– isherwood
3 hours ago
Not so much anticipation of damage.But for the future.
– Robert Moody
3 hours ago
Not so much anticipation of damage.But for the future.
– Robert Moody
3 hours ago
1
1
"FOR THE FUTURE", RUN CONDUIT NOW. Conduit is the most future-proof technology there is for wiring. Pull out the obsolete, pull in the up to date, done.
– Ecnerwal
2 hours ago
"FOR THE FUTURE", RUN CONDUIT NOW. Conduit is the most future-proof technology there is for wiring. Pull out the obsolete, pull in the up to date, done.
– Ecnerwal
2 hours ago
add a comment |
Robert Moody is a new contributor. Be nice, and check out our Code of Conduct.
Robert Moody is a new contributor. Be nice, and check out our Code of Conduct.
Robert Moody is a new contributor. Be nice, and check out our Code of Conduct.
Robert Moody is a new contributor. Be nice, and check out our Code of Conduct.
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WiFi is actually quite the opposite - cuts down on the need for wires. But typical is a WiFi thermostat in the location of a regular thermostat - same number of wires as "normal". Also, unlike phone/ethernet/etc., thermostat wire is a bunch of separate wires, not actually pairs.
– manassehkatz
3 hours ago
1
What is normal,? No less than 5.
– Robert Moody
11 mins ago