Wireless Programmable stat query??

[glowboy77]

Airing of side of caution, 12500 watts output from all rads.

 

[D_Hailsham]

Airing of side of caution, 12500 watts output from all rads.

That's OK. If you allow another 2kW you get 14.5kW, which is almost the size of the boiler.

The SBV33 is the bypass valve.

Check how hot the outlet pipe (far side from the pump) gets when you have heating only and when you have both heating and hot water.

I can't see any mention, but do you have TRVs on any rads?

Which pump do you have?

 

[glowboy77]

TRV's on all rads except one in hallway where stat is.

Pump is a Grundfos 130?, turned up to full speed (3).

CH and HW on at mo, outlet pipe v hot. Will let you know how it gets on when just CH on.

 

[D_Hailsham]

TRV's on all rads except one in hallway where stat is.

Which came first, the TRVs or the bypass valve?

Pump is a Grundfos 130?, turned up to full speed (3).

Probably a 15-50 Selectric or a 15-60 Super Selectric. It will say on the round data disk on the front.

CH and HW on at mo, outlet pipe v hot.

That shouldn't be happening! but were you testing right next to the valve or some distance away?

Will let you know how it gets on when just CH on.

OK.

 

[glowboy77]

Which came first, the TRVs or the bypass valve?

System as new installed in a new house circa 2006, have not made any adjustments other than replacing dial room stat for digi stat so bypass valves and TRV's there from same time.

That shouldn't be happening! but were you testing right next to the valve or some distance away?

Testing right near valve?? Do you mean bypass valve??[/quote]

 

[D_Hailsham]

System as new installed in a new house circa 2006, have not made any adjustments other than replacing dial room stat for digi stat so bypass valves and TRV's there from same time.

What's the betting they didn't bother to balance the system on the basis that "systems with TRVs don't need balancing"? Wrong! Download and read Drayton's TRV Commissioning Guide

How to balance a CH system is a step by step guide.

Testing right near valve?? Do you mean bypass valve??

Yes. If you are checking the temperature immediately next to the valve, you may get a false reading from heat transmitted through the metal of the valve. Check about a foot away.

 

[glowboy77]

Cheers,

I'll try that when i get the chance. Contact thermometers, expensive?,

Am i right in thinking there should be a noticeable difference in temp of flow and return pipes from boiler as well?

Having a quick look at it, it appears some TRV's may be on wrong side ie the return, due to where heats up first when from cold?

Silly mistake like that makes me think they prob ain't comissioned it spot on, useless!!

 

[D_Hailsham]

Contact thermometers, expensive?,

An Infra red thermometer cost about £20 from Maplin and is faster; it also has other uses. You need to wrap some black insulating tape round each pipe and measure the temperature of the tape. This is because the heat emission varies with the type and shininess of the surface.

Am i right in thinking there should be a noticeable difference in temp of flow and return pipes from boiler as well?

Yes. You should find the design temperature drop in the Installation Manual. Post the boiler make and exact model if you can't find the info.

Having a quick look at it, it appears some TRV's may be on wrong side ie the return, due to where heats up first when from cold?

That may not matter. Have a look on the metal body of the TRVs for one arrow or two arrows at right angles. If the TRV has two arrows, it can go on either end, If only one arrow, this must face in the direction of flow - toward the rad on the hotter pipe, away on cooler pipe.