DIY Home Improvement, Remodeling & Repair Forum

DIY Home Improvement, Remodeling & Repair Forum (
-   Plumbing Forum (
-   -   Circulator pump questions... (

akradar 12-04-2006 09:10 AM

Circulator pump questions...
I have a system where the hot water tank is just a storage advice, meaning it's not wired for electric or plumbed for gas, the boiler does the heating. I have in line for the water (potable) a circulator pump that keeps water flowing through the system for quicker hot water at the taps. Now, is this thing SUPPOSED to run all the time? It has a merc switch thermostat right next to it, and it appears to be set to about 150-175 degrees, but it's ALWAYS on. It's one of those things that just get me wondering sometimes. Incedentally, I had some work done about 2 years ago, and that plumber reset the thermostat on it's side, for door clearance, and it never came on. That's when I found out about the merc switch, and after righting it again, it started circulating. Anyhow, what can you folks tell me about that?:D

glennjanie 12-04-2006 04:31 PM

Hello AKradar:
It sounds like the temperature is not reaching the cut-off point or the thermostat is stuck (or out of level enough to offset the mercury). In Kentucky we don't heat domestic water above 140 degrees except for a commmercial dishwasher, which is set at 180 degrees but the water can't be piped to any other outlet unless it goes through a tempering valve.
Try reseting the thermostat and make sure it is installed perfectly level. Water over 140 degrees will scald your skin in a flash, you can't hold your hand under 140 degree water over a few seconds.
Water, under certain conditions, will circulate itself without the pump just by convection. You may need to insulate the water tank and all piping to keep the hot water flowing. Use a fiberglass blanket on the tank and either rigid fiberglass or closed cell foam (Armaflex) on the pipes. Let us know how it turns out.

akradar 12-05-2006 08:48 AM

I was wondering about that as well. The pipes are definately not covered, will that foam stuff melt or something like that? I would think not, but thought I'd ask. I guess you just cover and tape, or will zip ties work better? I give that thermostat a look as well, I have burned myself once washing my head in the tub, and frankly, I can't afford the hair loss, it's going fast enough as it is.:D

glennjanie 12-05-2006 09:24 AM

Hello AKradar:
No, the closed cell foam will not melt until it is somewhere above 200 to 250 degrees. Some brands are bought with a split down the side and paper covering the adhesive; you slip it over the pipe, pull the paper out of the splice and squeeze it together. Others have only the slit and you add rubber cement to hold it. I wish you well with the project and Merry Christmas!

All times are GMT -6. The time now is 11:39 AM.