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Phil, Mechanical Engineer.
Category: Plumbing
Satisfied Customers: 8517
Experience:  Retired mech. contractor, shop owner, 51 yrs experience.
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i have a 2 story rancher, hot water baseboard fuled by oil.

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i have a 2 story rancher, hot water baseboard fuled by oil. I have one zone for the bottom and top. The top will be vacant this year, can I not heat the top floor where as the bottom will be heated. I wanted to close the top floor down, my contractor said I need to heat both floors for fear of water pipes and heating pipes freezing. Is this correct.
Welcome to Just Answer!

Your contractor is correct. However you can just set the thermostat down to 50F, that will keep the area from freezing and dry enough to prevent mold growth.

Let me know of you need more information or an explanation we can go from there.

Phil and 2 other Plumbing Specialists are ready to help you
Customer: replied 3 years ago.

ok then but can I get the temperature a bit lower to say 45?


10:36 am, Thursday 10/10/13: Wondering if this question was answered. Oil fuel is costly where we're located, the boiler older and I'm asking if there is a way to adjust the thermostat below the reading on it to say, 45. This is 13 degress above freezing and I don't see why this wouldn't guarantee the pipes won't freeze.


Much Thanks.

Hello again, it will not be a problem locating a heat only thermostat that will control down to 45F... I need to know if the voltage going to the thermostat is 24 volts or 110 volts and how many wires are attached to it.... or... even better, the brand and model number of the thermostat.

Depending on what you have, I can find something but it might take a few hours.

Let me know, we can go from there.

Note: on this end I stay with you until you get the full and complete answer you need, but I have to come and go in that time frame.

Customer: replied 3 years ago.


I will need to contact my contractor who maintaims the home which is out of state. I'll try for an answer by tonight or tomorrow depending on reaching him. I'll be as quick as posible to wrap this up for the both of us.

Much Thanks

Hello again, there is no rush on this end... there are no time limits here.

If the contractor installed the heating system he will know all about the thermostat, if he did not install it he will have a hard time finding out unless he visits the property... You may have demount the thermostat yourself and take a look.

Customer: replied 3 years ago.

Hi Phil,


Thanks on the thermostat, the contractor will look at it. I go found out the upstairs is 2 zoned, 1 for the 3 bedtrooms,1 bathroom in the back of the rancher, the other for the rest of the home, the small hallway one bathroom LR, Kitchen and Dining Room. I want to shut the bedroom thermostat off, is this advisable or once again do I neeed to run it at a minimal temperature. As a reminder, we have a oil burner andbaseboard heat?


Hello again, This sort of thing can get complex... since it is *already zoned. simply installing a new thermostat that goes down to 45F, and setting it to 45F should work to hold that zone to 45F and put the rest of the heat to the first floor living areas...

We should try that first, and see if it functions as desired. That is apparently how it was designed... if that fails, then the zone control system is not wired or piped correctly.. thats a much more involved project... we can look into that when the time comes.

I am traveling now and for the next few weeks, I will check in occasionally, that should work in this case... let me know if that will be OK.

Customer: replied 3 years ago.



I perhaps wasn't clear on this, the first floor is 1 zone, 4 rooms, and is rented and will be heated by the tenant. the whole house runs off of the same oil burner. The 2nd floor with the 2 additional zones is where I want to shut one zone for the back rooms and run just the one zone for the living areas at a 45 degree temperature.

Thanks for your patience and responses.

Hello again, for the tennant to pay for heating the first floor entirely you have to turn off the boiler water flow to he first floor.. or install a thermostat that can be set and locked at 45F for the first floor so that the pipes don't frees if if he fails to use whatever other heat he provides to heat the first floor.

Then you can use your two existing thermostats upstairs to zone those, just set the thermstat in zone you are not using down to 45F or 50F depending on which thermostat you have and that will operate the zone system.

Note: I may not be a good idea to try to figure this out on line here because the wiring and pipe or duct sizing can be quite complex.. It is not uncommon to spend 8 or 10 hours on site figuring out how to do something like this and another 2 hours getting the right thermostat...

Let me know if you wish to continue with me or not, we can go from there.

If you do, II will need a photo copy of the existing system wiring diagram, the thermostat wiring diagram for each thermostat and how each is actually wired, I will need the same data on the zone valves or pumps, and the zone controller wiring diagram in that case... and arragements to spend a lot more time witn you.

Customer: replied 3 years ago.

Hi Phil.


I believe I have a handle on it now.


Thanks for your help.