Expert: Dan Griffin - 11/19/2008

Question
QUESTION: Hi Dan, I want to ask first before I ask the question I have. Did you ever install outdoor hot box enclosures for weather protection of water lines or valves or something like that?

ANSWER: Bill, we've not added heat to ours at this point.  I built some insulated "dog houses" to cover some, but what we found is that coaches would not put them back on after they had recharged the system.  We kept the houses to protect the back flow preventer risers, but installed a system of unions on the risers and we remove the backflow preventers for the winter months.

The ideal circumstance would be to install the bp inside the conditioned space, in our case an outside wall mechanical space to totally prevent the issues.

A heated enclosure is quite normal for anyone with a well house and there is a great deal of information out there.

---------- FOLLOW-UP ----------

QUESTION: Dan well here is me question. I just put in a fiberglass box 36" tall x 40"long x 16" wide. I have a 18 ft. regulated heat cable on pipes and backflow in there. The box has 1" foam insulation glued to the walls, I added 1" thick insulation foam board, same stuff as glued to wall but I cut it perfect and just slid it in all around the inside of box. And I put a automotive rubber seal around the lid to make box just about air tight so it stays warmer. But I have noticed a lot of condensation on the foil of the insulation board I put in there. Do you think when the cable heats up and the radiant heat heats up box that will stop and go away? If not have you seen this before and is there anyway to stop the condensation on the inside walls of the box?

Answer
Bill, where are you?  It hasn't gotten cold enough here for any of this to be an issue.  If the box is sweating on the inside, it would seem to indiacate that the box walls are colder than the interior, especially the heated pipe area.  I don't know how much moisture you are talking about, but I don't think I would worry about it much.  It sounds as if you have dealt with the issues.  Really cold air has little moisture in it.  How do you have the opening/bottom/whatever sealed?  I assume you have made every effort to keep the box well sealed to air infiltration.