1/2\" water pex for heat??

[Deleted User]

Yes to the current contractor and no to the original installer. The original installer is trying to cut corners and shouldn't. You shouldn't have to induce glycol for his short comings, and you shouldn't have to pay the extra parasitic cost of operation of a bigger pump that would then move the water through the tube at a higher velocity than it was designed for, resulting in an early tube failure. Nor should you have to pay for an upgrade of a pump that had he put the proper sized tube in there, it would not be necessary.

Did the original installer give you a "REAL GOOD deal"? Was his price significantly less than the competition?

Just curious about how this stuff "happens". He (the original installler) should have (and obviously does) know better than to try and pull that crap.

You DON'T want glycol unnecessairily induced into your system, and you DON'T want a bigger screaming pump in there.

ME

AnneB

1/2\" water pex for heat???

Hi there-
I am a homeowner that just bought a house. The boiler needs to be replaced and a contractor is installing a Knight boiler. He says that the previous installer piped the 2 zone baseboard system with 1/2" water pex. He says this needs to be replaced because a) there is approx. 60' of baseboard on each zone, and he says the 1/2" will never heat the baseboard properly and b) the pex should have an 'oxygen barrier' otherwise it will eventually corrode the cast iron components of the system. My question is this- the original installer says that we can install glycol in the system and that will negate the need for pex with the oxygen barrier- is this correct? The original installer also says that if we take out the Taco 007 and put in a Taco 009 or 0011 this will make up for the fact that the piping is only 1/2". Is this accurate? Thanks for your help!!

Timco

Has either installer done the math on sizing your pipe / system? Heatloss? These things will size your piping, which will size your circ. The 007 should run your system fine, with correct pipe. 1/2 is really small for your runs, and should be 3/4. as for the type, I would only use h-pex or pex-al-pex.

Tim

Weezbo

i have a feeling that you may be in for more suprises....

often when you can see there are things like no O barrier and then you come to find that things just never worked right ....there may be things you dont see.... buying a new home you would do yourself a favor to find a building inspector with residential endorsements to look at it first.

while there is a way to blast fluid through a 1/2" pipe at twenty feet per second it is doing a few detrimental things to the pipe... the larger circ pumps are not an answer, nor adding antifreeze...the zones need to be reconsidered when you replace the pex ... you may end up with three or four depending on variables of construction. it is difficult to understand some things when that is not your line of work however we have an excellent Library here ....look at the top of the page and you will see SHOP that has some informative yet comfortable, reading material available,... written in consideration of novice to master ..it isnt a bunch of numbers and mathamatical abstracts ...it is day to day, useful ...you can give a book like this to anyone and they would enjoy the read.... *~/:)

as you are going to install a new boiler , have you been given any options for heat emmitters?

burninben

SAD SAD SAD

Sorry Anne but there are scammers in our business. I would report the original installer of the system to your local better business bearau. No oxygen barrier is fine if you do not have any ferrous metals in you system, as for the half inch pipe. I would say you'll have to change it. You'll end up with a whole new can of worms if you don't. As for your new contractor it sounds like he's got it together. It's too bad you had to inherit someone elses problem.

Contractor

what your contractor means by putting glycol in the system to solve that problem is adding a heat exchanger with it so that the water going through your baseboards never touches any other part of your system, kind of like a snow melting system.

as for 1/2" i would bump that up to 5/8" or 3/4" depending on the heat load needed and dont upsize your pump like everyone else has said. use the O2 barrier pipe with no glycol and youll be good. your first installer didnt sound too knowledgable on the issue. consult with the manufacturer of the PEX also if you have any concerns.