Regency P90 Propane Fireplace/Thermostat Wiring Problem

[mgh-pa]

Alright, I'll keep this abbreviated. Two years ago, my father an I gutted our family room, and in the process, we replaced the old existing wood stove and slate hearth with a built in propane fireplace insert around a custom stone veneer fireplace. We did the actual build and placement of the unit, and the retailer I purchased from hooked all of the lines up. In the process, I opted for a traditional wired thermostat control, but wasn't there for the actual hook up (this was two years ago mind you). The retailer did not bring the thermostat, so he bought a junk one from a local hardware store and installed it. When I came home, the thermostat didn't work (shocker), and it appeared that nothing was wired correctly. I could still operate the fireplace manually, and my dealings with the retailer (he's 45 minutes away) were less than great, so I decided to live with it, and fix it myself.

Well, two years later, and I'm finally getting around to it. I purchased a new millivolt thermostat (one that was programmable and not appearing to be from the late 1970s) and wired everything up according to the wiring diagram, but it still doesn't work. I can completely disconnect the thermostat, and the burners are still lit.

Here's the wiring diagram:

Here's the picture of the wires as it stands now:

The valve is oriented EXACTLY in the same way as the diagram. The heavier gauge red, white, and black wires are from the thermostat/burner control. The thinner gauge wires are from the thermostat.

I spliced the "On" wire from the the T-Stat to the white wire from the burner/thermostat, and then ran the "off" wire (white) from the T-Stat directly to the valve. The Thermostat has blocks that are labeled Y an G, and then a three block section labeled "Rh, Rc, and W." I used the Rh and W blocks, but I'm not sure (the manual didn't specify) if that could be the problem.

Anyone have any suggestions?

 

[SmokeyTheBear]

I can't speak to the stove side but Rh and W is correct on the t-stat side.

Can you tell us the stove make and model.

 

[mgh-pa]

It's a Regency Excalibur P90.

 

[DAKSY]

Alright, I'll keep this abbreviated. Two years ago, my father an I gutted our family room, and in the process, we replaced the old existing wood stove and slate hearth with a built in propane fireplace insert around a custom stone veneer fireplace. We did the actual build and placement of the unit, and the retailer I purchased from hooked all of the lines up. In the process, I opted for a traditional wired thermostat control, but wasn't there for the actual hook up (this was two years ago mind you). The retailer did not bring the thermostat, so he bought a junk one from a local hardware store and installed it. When I came home, the thermostat didn't work (shocker), and it appeared that nothing was wired correctly. I could still operate the fireplace manually, and my dealings with the retailer (he's 45 minutes away) were less than great, so I decided to live with it, and fix it myself.

Well, two years later, and I'm finally getting around to it. I purchased a new millivolt thermostat (one that was programmable and not appearing to be from the late 1970s) and wired everything up according to the wiring diagram, but it still doesn't work. I can completely disconnect the thermostat, and the burners are still lit.

Here's the wiring diagram:

Here's the picture of the wires as it stands now:

The valve is oriented EXACTLY in the same way as the diagram. The heavier gauge red, white, and black wires are from the thermostat/burner control. The thinner gauge wires are from the thermostat.

I spliced the "On" wire from the the T-Stat to the white wire from the burner/thermostat, and then ran the "off" wire (white) from the T-Stat directly to the valve. The Thermostat has blocks that are labeled Y an G, and then a three block section labeled "Rh, Rc, and W." I used the Rh and W blocks, but I'm not sure (the manual didn't specify) if that could be the problem.

Anyone have any suggestions?

Run the white wire from the T-Stat directly to the screw where the red wire from the switch is & give THAT a try. Leave the switch in the T-Stat position on the unit. Lemme know if that works...

 

[mgh-pa]

Should I remove the red wire from the switch first? There is no room there as it stands. One existing wire under the screw goes to the thermopile (as per the diagram above), and the wire connected to the spade terminal is from the switch.

 

[SmokeyTheBear]

I have a question for you what position do you have that switch in when the t-stat isn't working ?

Is it a three position switch as in on off and thermostat as the diagram is hinting at?

That t-stat is just a switch that connects THTP to TH to fire the stove, this is the same thing that the switch does in on position.

One of your t-stat wires should be going to that switch and the the other to TH on the valve.

Then the switch on the stove can do on/off duty or allow use of the t-stat.

 

[DAKSY]

Should I remove the red wire from the switch first? There is no room there as it stands. One existing wire under the screw goes to the thermopile (as per the diagram above), and the wire connected to the spade terminal is from the switch.

Loosen the screw & attach the wire along with the Thermoplie wire.

 

[mgh-pa]

Thanks, guys, will give this a go when I get home this afternoon.

The switch is in fact a three position switch, but, as it stands, the T-Stat has no affect on the burner control when set to either T-Stat, or manual mode. Only manually switching the switch to "OFF," or the middle position, do the flames go off.

Here's a picture of the switch:

As I stated, I have have the white wire from the T-Stat going to TH (the bottom terminal pictured above). The Red wire of the T-Stat is spliced to the white wire of the switch. Then the black wire of the switch is wired directly to TH as well, and the red wire is wired directly to THTP.

 

[SmokeyTheBear]

Then it is as I said the wire that you are attempting to hook up to THTP on the valve goes to the unused spade on that switch.

That switch controls who has access to THTP when the switch is in t-stat the t-stat controls the stove when that switch is off the stove is off regardless of t-stat setting, when it is in the on position the stove is on regardless of the t-stat.

 

[mgh-pa]

Then it is as I said the wire that you are attempting to hook up to THP on the valve goes to the unused spade on that switch.

That switch controls who has access to THP when the switch is in t-stat the t-stat controls the stove when that switch is off the stove is off regardless of t-stat setting, when it is in the on position the stove is on regardless of the t-stat.

Ah ok, so that white wire (from the T-Stat) actually goes to the middle terminal, not the bottom?

Looking at the diagram, it's a little confusing. If the switch (not the t-stat) is switched to regular "ON", it looks as though the path goes through the T-Stat (identified by the dashed line), but when when the regular switch is set to "T-Stat", it's just directed straight to the valve? My schematic reading skills aren't quite brushed up, so please forgive the ignorant questions, but I'm just trying to learn here.

 

[SmokeyTheBear]

There should be three terminals on the switch two the red and black wires were connected to, the empty one should have the wire you are trying to cram on to the THP terminal on the valve attached there instead.

The second t-stat wire gos to TH on the valve.

The switch on the stove is a single pole double throw center off switch.

When it is in the ON position it connects TH to THTP and the valve opens and the stove fires up.

When it is in the OFF position there is no way for TH and THTP to be connected so the valve stays closed and stove stays unfired.

When it is in the thermostat position control is transfered to the t-stat to connect TH to THP to open the valve and fire the stove or disconnect TH from THTP closing the valve and stopping the firing of the stove.

 

[mgh-pa]

Alright, back home now. I have a TPTH on top, TP in the center, and TH on the bottom. No THP. Red from switch goes to TPTH, black from switch goes to splice on one end of the tstat, black from switch goes to TH, and other side of tstat goes to TH. Gas works with switch in Tstat mode even with the tstat off.

TP is the only one unused (except for factory wire running to Thermopile).

 

[SmokeyTheBear]

Alright, back home now. I have a TPTH on top, TP in the center, and TH on the bottom. No THP. Red from switch goes to TPTH, black from switch goes to splice on one end of the tstat, black from switch goes to TH, and other side of tstat goes to TH. Gas works with switch in Tstat mode even with the tstat off.

TP is the only one unused (except for factory wire running to Thermopile).

I didn't see the second T in the THTP. My blunder on the name.

That switch should have three tabs on it two of the tabs were already connected to the valve. You put one of the t-stat wires on the empty tab on the switch and the other on TH.

I've corrected my miss label on all of my prior posts.

 

[DAKSY]

Alright, back home now. I have a TPTH on top, TP in the center, and TH on the bottom. No THP. Red from switch goes to TPTH, black from switch goes to splice on one end of the tstat, black from switch goes to TH, and other side of tstat goes to TH. Gas works with switch in Tstat mode even with the tstat off.

TP is the only one unused (except for factory wire running to Thermopile).

The terminals with TH, Including TH-TP (or TP-TH) are where you want your switch to be. Think of TH as THermostat. If you remove the switch wires, replace them with your thermostat wires. That may not be the
way the wiring diagram shows you, but it should allow you to control the unit with the T-stat. Of course it takes the switch out of the loop. Like I said in the earlier post. You can hook BOTH to the same terminals & either one will control the unit. What you have to remember is WHERE you turn it on is WHERE you turn it off. Clear as mud, right?

 

[mgh-pa]

The terminals with TH, Including TH-TP (or TP-TH) are where you want your switch to be. Think of TH as THermostat. If you remove the switch wires, replace them with your thermostat wires. That may not be the
way the wiring diagram shows you, but it should allow you to control the unit with the T-stat. Of course it takes the switch out of the loop. Like I said in the earlier post. You can hook BOTH to the same terminals & either one will control the unit. What you have to remember is WHERE you turn it on is WHERE you turn it off. Clear as mud, right?

Ok, there are no spades on the back of the switch. It came hard wired, with the valve ends having spade conductors already on them. I get what you guys are saying, but the one side of the tstat is hooked up to the TH on the valve and the other end is just spliced to the white lead from the switch.

 

[SmokeyTheBear]

Then what happens when you place the switch in the thermostat position?

 

[mgh-pa]

Then what happens when you place the switch in the thermostat position?

Stove keeps running regardless of tstat.

 

[SmokeyTheBear]

You need to check the wiring at that switch out.

ETA: And also your wiring back at the t-stat for a short across the Rh and W terminals.

 

[mgh-pa]

You need to check the wiring at that switch out.

ETA: And also your wiring back at the t-stat for a short across the Rh and W terminals.

Now that you mention the tstat, there was a jumper installed by the factory between the Rh and Rc terminals. I left that in, and ran red to that, then white to the W. Could that be the problem?

 

[SmokeyTheBear]

What mode did you tell that stat it was to operate in?

It should be heat mode. You shouldn't need to remove that jumper but it does tie the cooling and heat actions of the stat together

 

[mgh-pa]

I set it to heating.

 

[SmokeyTheBear]

Well pull that jumper.

If that doesn't do it.

Lift one of t-stat wires off its screw on the t-stat.

ETA: What t-stat did you buy?

 

[mgh-pa]

Fireplace still works with the wires pulled. It's a honeywell rth221.

 

[SmokeyTheBear]

What does it do when you set it to thermostat on the rocker switch?

If it doesn't go to pilot the the next thing is to remove your t-stat connections at the stove.

ETA: I'm checking out, I've been up since 3:00 this morning and am getting a bit sleepy.

 

[mgh-pa]

I hope you weren't staying up on my accord You've been a huge help (as everyone else has here, too). So I just went down this morning, and disconnected the wire coming from the T-Stat to TH (disconnected at the TH terminal), and NOW when the switch is in T-Stat mode, the burners don't light.