replaced infloor heating lines and it doesnt work well!

[piperken]

the original floor was steel and worked terrific but 2 years ago we tore it up and replaced it. The company used 1/2" plastic with 2 feeder lines going into the bay. the bottom line is when the temps go below -8 the bay freezes up and you wouldnt know there is a coil in the floor. we have uped the temp to 140 and reduce flow to another bay and it is better but pretty much frozen up. Anybody have any knowledge on this matter?

 

[OurTown]

How close to the surface were the lines put in?

 

[piperken]

Im not sure how deep they were but when they where installed, i would guess and say 2 to 3" of concrete overtop of the PVC.

 

[cantbreak80]

“The company used 1/2" plastic with 2 feeder lines going into the bay. the bottom line is when the temps go below -8”

So, a few questions to help me understand…

One loop is 2 to 3” below the finished floor, and the second loop is below the first loop?

Are there multiple loops in this bay or just the two high and low loops?

What are the bay dimensions?

Is the system an open or closed loop system?

 

[dreese]

the original floor was steel and worked terrific but 2 years ago we tore it up and replaced it. The company used 1/2" plastic with 2 feeder lines going into the bay. the bottom line is when the temps go below -8 the bay freezes up and you wouldnt know there is a coil in the floor. we have uped the temp to 140 and reduce flow to another bay and it is better but pretty much frozen up. Anybody have any knowledge on this matter?

IMHO, your installer was probably used to installing radiant heating in a building, not in a car wash. You are facing a flow issue - the fact that forcing more fluid thru the tubing by restricting flow in another bay "makes it better" tends to support this.

Again IMHO, 1/2" tubing typically does not carry sufficient volume to efficiently deice a bay. A minimum of 5/8" tubing should have been used, I personally design deice layouts using 3/4" tubing placed 12" on center.

That being said, depending on the length of the individual loops within the bay you could try to upsize your circulating pump to force more volume thru the system.

 

[Roz]

8 Below is cold. We had a check valve burst (associated with the IBA undercarriage pipe) from the cold when the wind chill took the 10 deg temp down to -9. Not certain any heated floor can keep up with negative temps. We shut down the IBA at 20 deg just to play it safe and to keep the doors closed to preserve the heat inside. We opened up the IBA too soon after the temps rose above 20 which led to the burst valve. Thinking of changing the temp cutoff to a higher number. 99.9% of our customers totally understand when we decide to shut down the system.

The SS bays are fine as we had extra piping installed in the floors when we redid them (used 10-12" spacing instead of 16" which supposedly is the norm as it gives us better coverage). We also use a temp laser to adjust the flow to each bay so temps are consistent across them. (IE closest bays need less flow than furthest bays)

 

[OurTown]

Being in Canada it might be -8 Celsius which would be about 18F.