Condensing Pipe work.

[Bodd]

Combination Boiler

Hello All

Just run a near complete Heating system. all surface pipe work.
The problem is that the main is condensing. Not much I can do about this, or is there.

Of cousre the main can be lagged, where it comes down walls they are in cupbaords vetically so not a problem. But the customer intends to box in high level horizontal runs, should they lagg the main or would it be wise just to box in the pipe work unlagged.

Bod

 

[GQuigley67]

any boxed in pipework should be lagged to be honest, if that froze then how are you going to thaw it out before it does any damage ?

good ventilation also prevents condensation

 

[Bodd]

Thanks for getting back to me GQ

Horizontal pipe work run in front hall and bedroom. Not much chance of frezzzing.

So your saying lag hot Cold, flow and return, but leave ventalation at each end (all boxing will begin and end at a cupboard so would be easy to leave open.

Bod

 

[GQuigley67]

no just lag boxed in pipework no ventilation in the boxing in, i mean if exposed pipework has condensation on it then fitting an air vent might solve this problem as the customer may not want exposed pipework lagged.

 

[Blackcatgas]

Ive lagged pipes under sinks before to stop condensation, all that happens is that you get even more localised condenastin on the bits that you cant lag so it makes it look like they are leaking.

 

[GQuigley67]

im doing building science as part of my HNC construction course and at the moment we are learning about condensation, best way to get rid of it is ventilation its because the air is too moist and when it touches the cold pipe it condenses if you fit an air vent the air will get continously replaced with fresh air and should prevent a build up of water vapour in the air.

 

[dai the plumber]

If water is condensing on the pipework the general cause will most probably be high humidity. If you have not had any heating the air temperature will probably be lower the normal and cold air is unable to contain as much moisture as warm air. Also in many houses with double glazing etc, there is poor ventilation which in effect 'waterlogs' the air, this water then condenses out on any cold surface.
A small domestic dehumidifier may remove some of the moisture in the air, as will opening several windows, but if the relative humidity outside is high( like it's raining) you may just import more
moisture and exacerbate the issue.

I agree that insulation may help but anywhere the incoming remains uninsulated will sweat like a stuck pig and look like it's leaking. Check the relative humidity and impress the customer with your thoroughness and capability.

 

[Bodd]

If water is condensing on the pipework the general cause will most probably be high humidity. If you have not had any heating the air temperature will probably be lower the normal and cold air is unable to contain as much moisture as warm air. Also in many houses with double glazing etc, there is poor ventilation which in effect 'waterlogs' the air, this water then condenses out on any cold surface.
A small domestic dehumidifier may remove some of the moisture in the air, as will opening several windows, but if the relative humidity outside is high( like it's raining) you may just import more
moisture and exacerbate the issue.

I agree that insulation may help but anywhere the incoming remains uninsulated will sweat like a stuck pig and look like it's leaking. Check the relative humidity and impress the customer with your thoroughness and capability.

Ok Dai I'm listening.

How do I check the humidity?

 

[tamz]

If you have run all the pipes F&R, H&C together no wonder it is condensing.
If you have, the cold pipe should have been the bottom pipe. Insulate all the pipes and glue the joints.

 

[Bodd]

If you have run all the pipes F&R, H&C together no wonder it is condensing.
If you have, the cold pipe should have been the bottom pipe. Insulate all the pipes and glue the joints.

Guilty

I did run the Cold on bottom of all runs. Used talon clips, from combination boiler, had limited space so not much choice.

Old style flat converted from big early centry house, no ventilation, so advised ventilation a nd lagging may be way to go.

Thanks Tamz

Bod